Download Seamobile Guide 2001 - Natural History Museum of Los Angeles

Seamobile
Teacher Guide
NATURAL H I STORY MUSEUM
O F
L
O S
A
N G E L E S
C
O U N T Y
E DUCATION D IVISION
with generous support from the
Maxwell H. Gluck Foundation
Seamobile
Teacher Guide
= core activities
= materials found in Seamobile teaching kit
Contents
1. Introductions
What is the Seamobile?
3
5
Introduction
The Los Angeles Tides
2. Investigating
Another World
How have humans learned
about the oceans?
6
7
6. Life Beneath
the Waves
Background
Activity: What’s Up Down There?
How do plants and animals
survive in these watery
environments?
34
36
42
7. Making Sense of It All
How can scientific data help
us better understand what is
happening in a marine habitat?
3. The Marine
Environment
What are the physical
conditions of the oceans?
9
10
Background
Activity: That Sinking Feeling
4. Finding Your Way
How do we know where we
are and where we’re going?
12
14
17
22
Background
Activity: Map Building
Activity: Getting Your Bearings
Activity: How Far? How Long?
5. Classifying Creatures
How can we identify plants
and animals based on physical
characteristics?
25
26
29
32
Background
Activity: Odds and Ends
Activity: A Key to California
Marine Shells
Activity: Invent a Key for
Echinoderms
Developed and Edited by:
Natural History Museum of Los Angeles County
Education Division
Art Department
February 2001
2
Background
Activity: Squid Dissection:
From Pen to Ink
Quick Info: About Squid
43
44
52
Background
Activity: Completing the
Seamobile
Career Focus: Oceanography
8. Caring for an
Ocean Planet
How do we affect the health
of our land and oceans?
53
55
58
59
60
Background
Activity: Gone Fishing
Quick Info: About Fishing
Activity: Too Much of a Good Thing?
Activity: What a Mess!
Appendix
65
66
67
68
A Measurements and Conversions
B Glossary
C For More Information…
D Echinoderm Photos
Special Thanks to:
California Department of Fish and Game, Monterey
Monterey Bay Aquarium Research Institute
Moss Landing Marine Laboratories
National Oceanic and Atmospheric Administration
National Marine Fisheries Service
West Coast National Undersea Research Center
United States Navy
Natural History Museum of Los Angeles County
Introduction
What is the Seamobile?
When we visit the beach, we often appreciate the cool waves, the fresh ocean breezes and the
warm sand beneath our feet. But what is happening below the waves, in the places that we
can’t see from above? Through the resources of the Natural History Museum of Los Angeles
County and the generosity of the Maxwell H. Gluck Foundation, students can use the Seamobile
to explore the ocean depths and take a closer look at the effects that humans have on ocean habitats.
Introduction
The interior of the Seamobile recreates a scientific research submersible where students embark
on a simulated dive beneath the ocean off the coast of Southern California. On board, they take
the role of scientists, investigating the plants and animals of the local marine environment and
collecting data to better understand what is happening there.
The activities included in this Teacher Guide were created to meet the recommendations of
the National Science Education Standards. They were written and developed by museum
educators and classroom teachers with the intention of providing interdisciplinary lessons for
grades six through eight that could be easily adapted to a variety of learning environments.
How To Use This Guide
The Seamobile Teacher Guide was designed to provide teachers with ideas and suggestions
of how the Seamobile experience might be incorporated into a unit on marine biology or a
pre-existing curriculum dealing with life science, ecology, or even aspects of physical science.
Furthermore, the student activities conducted on board the Seamobile, as well as those
presented here, reflect an emphasis on science process skills including classification, data
collection, data interpretation and hypothesis-making.
The Guide has been organized into six topic areas.
Topic
Ocean Exploration
Physical Conditions
Navigation
Organization and Classification
Marine Ecosystems
Data Interpretation
Environmental Issues
Chapter
Investigating the Ocean
The Marine Environment
Finding Your Way
Classifying Creatures
Life Beneath the Waves
Making Sense of It All
Caring for an Ocean Planet
Background information, for teachers or students, has been included in each of these
chapters to provide additional context. An appendix also includes a glossary, background
on measurement conversions, and a list of useful library and web resources.
As part of the introduction, we have also included a page from a mock newspaper,
“The Los Angeles Tides” which can be used to introduce the Seamobile, and the
importance of marine research.
Each of the activities described here has been designated as best for pre-visit (before students
enter the Seamobile) or post-visit (after the Seamobile session.) Several activities could be
used in either situation. Pay close attention to the core activities, as these pre-visit activities
have been found to be most effective in preparing students for their Seamobile “voyage”.
Natural History Museum of Los Angeles County
The core activities are
designated by a sea star
and include:
Finding Your
Bearings
Odds and Ends
A Key to California
Marine Shells
3
Introduction
Activities requiring
teaching kit materials
are designated by
a treasure chest.
Several of the activities recommended for pre-visit require additional materials provided in the
Seamobile Teaching Kit. Activities requiring these special materials are designated with a
treasure chest icon. Some of these kit-based activities, including Odds and Ends and Invent
a Key for Echinoderms, require materials which can be prepared by the teacher even without
the Teaching Kit.
Connections with other disciplines or areas of study have also been identified for each activity.
In addition, Activity Time provides an estimated time to assist with lesson planning.
Process Skills
Each of the activities included in this guide has also been classified according to the science
process skills it promotes. Eight different process skills, based on recommendations from the
Science Framework for California Public Schools (1990), were identified, as described below.
Observing involves using the senses to construct a view of the world and how it works.
Communicating involves relaying accurate information through language or symbols.
Comparing involves examining similarities and differences.
Ordering involves looking for patterns of sequence. Sequences can be linear or cyclical.
Categorizing involves creating groups or classifications based on common characteristics
Relating involves identifying interactions and cause-and effect events.
Inferring involves making meaning from concepts that are distant in time, space or scale.
Applying involves putting scientific knowledge to use in a new situation.
Assessment
The Seamobile Curriculum does not include sample tests. Instead, we suggest alternate forms
of assessment aimed at identifying student misconceptions and determining progress in
student understanding.
In most cases, students already have some preconceptions of a new topic or area of study, having
gathered ideas from experience in the world around them. Unfortunately, these preconceptions
may be inaccurate, and are often difficult to adjust or dispel altogether. One way to identify
misconceptions is simply by asking. At the start of the unit, tell students to fold a piece of paper
in half longways, then open to create two columns. Choose a topic, such as “The Ocean
Environment” or “Marine Animals” and ask students to write this title at the very top of their
page. Next, ask students to label the first column “What I Know Now” and the second “What
I Want to Know.” Students should then write what they already know about the topic in the
first column. Any questions they might have about the topic should be written in the second
column. Encourage students to write down what they think, even if they are not completely
sure. These lists can be used to identify some of the misconceptions that students may have and
consequently help with choosing activities which address these misconceptions or questions.
An assessment based on this activity might involve redistributing these papers at the end of
the unit and asking students to choose several of the original statements to either correct or
expand upon. This assessment provides the teacher with a real sense of what knowledge was
incorporated by the student during the unit of study. Another assessment might involve asking students to create a poster which describes, on one side, what they used to think,
and on the other side, what they understand now.
4
Natural History Museum of Los Angeles County
The Los Angele
s Tides
Today
Ocean Mystery
Baffles Local Sc
ientists
What is impact
ing the
underwater envi
ronment in
the
local
waters
off
Southern Califor
nia? That’s
what local scie
ntists would
like to know.
The area
under investigat
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from the Sant
a Barbara
area south,
past Santa
Monica and L
ong Beach
Harbor, to Coron
a Del Mar
in
Orange
County.
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preliminar y exam
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and animal
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Natural History Museum of Los Angeles County
Introduction Los Angeles Tides
35 cents
5
Investigating Another World Background
Investigating Another World
How have humans learned about the oceans?
Background
Ocean exploration is complicated. Humans can’t breathe oxygen from water like fish do. Nor
can they hold their breath very long, as whales and other marine mammals can. A snorkel
allows a diver to breathe surface air from a tube, but below a depth of two feet, the pressure
from the surrounding water makes it impossible to inhale air from the surface, no matter how
big the tube is. Yet these obstacles did not stop early ocean explorers from finding different
ways to explore the underwater world.
Diving
In 1530, the invention of the diving bell, a cauldron or bucket that traps air when inverted,
made it possible for divers to stay underwater for long periods of time. By the late 1890’s, a
forerunner of modern SCUBA (Self-Contained Underwater Breathing Apparatus) equipment
had been designed. The apparatus consisted of a steel tank of compressed air with valves
and hoses connected to a mouthpiece used by the diver. Throughout the 20th century, other
scientists and explorers like Jacques Cousteau improved greatly on the original design.
Undersea Vehicles
Over the past 400 years, underwater vessels have developed along two major lines – submarines
and manned submersibles. Submarines, typically designed for military use, have complex systems,
require large crews and have no viewports. The advantages of these vessels are their high speed
and ability to stay under for long periods of time. Manned submersibles are designed with
much better maneuverability and viewports for observation capability. Most submersibles are
battery operated, however, which limits their speed and underwater endurance. To conserve
power, most submersibles require a mother ship or tow vessel to bring them to and from the
study sites. Submersibles have been used to make many biological and archaeological discoveries.
Today, remotely operated vehicles (ROVs) have largely replaced manned submersibles for
deep-water exploration. ROVs are small machines, tethered from a surface ship or a manned
submersible, that consist mainly of motorized thrusters, cameras and lights. They are operated
remotely from above using heavy-duty fiber optic cables. ROVs can go into tight, deep spaces
where submersibles can’t; they are also cheaper to operate than submersibles.
The Seamobile simulates a submersible, although it is considerably larger than a typical vessel.
Submersibles typically hold 1-3 passengers—the Seamobile holds over 20! On board, student
research teams send an ROV to investigate a particular habitat within the local undersea environment.
6
Natural History Museum of Los Angeles County
Part A: Beginning Ocean Inquiry
1. Begin this project by asking students about some of the basic requirements for living creatures
in our environment. List the items as they are mentioned, guiding the discussion slightly
to include things like heat, shelter, light, and food. Then ask students whether or not
these things are available 3 feet underwater. How about 30 feet? 300 feet? 3000 feet?
Students should begin to discover how conditions for life become more limited as we
travel deeper into the ocean. (Leave this “basic requirements” list on the board for now.)
2. Next, ask students to take a piece of paper and fold it in half lengthwise, creating two columns.
Ask students to write “Deep Sea Environment” at the top of the left side; then ask them to
list short descriptions of what the underwater environment is like in that column. Descriptions
should be brief at this point; “dark”, “very cold”, “rocky floor” would be acceptable
descriptions. After a few minutes, ask students to share their ideas and create a master “What
is the environment like?” list on the board. If some of the points from the master list are
debated by students, indicate those with a question mark. The list is just a prompt—students
will be able to verify whether these descriptions are accurate later in the project. As you
complete the list, you may ask students to compare this new list with the first list. Are the
basic requirements for life (as you’ve listed them earlier) available in the deep sea?
Materials
nylon clothesline rope
kite string
paper clips
cardboard or cardstock
old magazines, markers,
colored pencils, etc.
Additional Resources
In order to complete their
investigation, students will
require access to library
and/or Internet resources.
Activity time
3. Ask students to write “Questions about the Deep Sea” at the top of the right side of their
paper. Direct students to make a list of five or more questions they have about underwater
ocean survival. A list of sample questions is included here.
What lives in the deep sea?
How do plants survive under water?
How do fish (or crustaceans or mollusks, etc.) survive in the deep sea?
How deep can marine mammals dive?
What do humans need to survive under water?
What problems do humans have when diving in deep waters?
What was the first device that allowed humans to breathe under water?
Where is the deepest part of the ocean and how was it discovered?
What is the depth of the ocean around Southern California?
How cold does it get in deep waters? How do animals survive here?
How do animals survive without light in the deep sea?
4. Group students in teams of 2 to 4. Ask each team to use the questions they’ve just developed
to create a master list of 4 questions that they would like to investigate as a group.
5. Collect these team lists and select one or two questions from each list for students
to investigate. By choosing the questions, the investigations can be guided somewhat,
eliminating excessive overlap of topics between groups and allowing for topics best
matched for student abilities.
Natural History Museum of Los Angeles County
2-4 days
Process skills
Communicating
Comparing
Relating
Connections
Language Arts
Using Library/Internet Resources
What’s Up Down There?pre-visit, post-visit
Working in teams, students will investigate the difficulties of
surviving in the ocean deep and discover how organisms
(including humans) have adapted to an unfriendly environment.
Investigating Another World
What’s Up Down There?
7
What’s Up Down There?
Part B: The Investigation
Teacher Tip: Prior to the
start of this project, you should
determine the format for the
final presentation. A brief
oral presentation (5 minutes)
or a short paper (1-2 pages)
would probably be sufficient.
Teacher Tip: You might
consider asking students
to convert all depth
measurements to metric units.
6. Each team will be researching one (or two)
of the questions that they’ve generated
using library resources and/or the Internet.
They will then present their findings to
the class in a pre-designated format.
7. In addition to the formal research
presentation described above, each team
will be required to create a depth card
based on their research. The card is a
visual display that shows how a particular
depth is related to each team’s research.
Each depth card should include a) an
image of some kind (drawing, painting,
magazine cut-out), b) a one-sentence
description, and c) a relevant depth reading.
For example, if a group’s question was
“Why are there so many living things near
deep sea vents?”, the depth marker might
include a drawing of deep sea vents, a
sentence describing what a deep sea vent
is, and a depth measurement of “3000m”.
See sample above.
8
8. The card can be made of any material
(cardboard, paper, etc.) Encourage students
to be creative, reminding them of any size
restrictions. These markers will be hung
for display, and should have a place
where string can be attached for hanging.
9. To complete their display, students will
measure and cut a piece of string that is
proportional to the depth indicated on
their card. In the sea vent example above,
a scale of 1 inch = 100 meters would result
in a string length of 30 inches. You might
ask the class to determine what would be
a useful scale. A paper clip for hanging
should be tied to the other end of the
string. Be sure that the entire class uses
the same length scale.
10. To complete the project, student teams will
present their findings to the class. The depth
cards, with the various string lengths, should
then be attached to the clothesline that is
stretching across a wall or across a corner of
the classroom. When finished, the “depth
line” will provide a unique reference and
display of the group investigations.
Natural History Museum of Los Angeles County
What are the physical conditions of the oceans?
Background
Physical Features of the Ocean
The ocean is spread over 139 million square miles, or 71% of the Earth’s surface. This is equivalent
to the surface area of 410 Californias! It occupies a volume of 329 million cubic miles and
weighs in at 155 billion billion tons. The average depth is 12,541 feet or about 2.4 miles and
the deepest part of the ocean, located in the South Pacific near the Philippine Islands, is the Mariana
Trench. The bottom of the Trench lies 36,163 feet (almost seven miles) below the surface.
Obstacles to Marine Exploration
The ocean is a harsh environment that is difficult to explore. Unlike fish, which pull oxygen
from the water through their gills, humans must bring air with them underwater. This is just
part of the problem; there are several other conditions that hinder our ability to explore the ocean.
Light. As light moves through the water, it is scattered and absorbed. In the open ocean, light
can only penetrate about 100 meters, while in coastal waters, only to about 40 meters. Even
in the clearest tropical waters, sunlight can not penetrate beyond 200 meters. If humans want
to explore the deep ocean, they must bring their light with them.
Temperature. Solar energy is the most important source of heat for the ocean. However,
the warmth of the sun’s rays can not reach past 250 meters. Eighty percent of the Earth’s water
is in this deep zone, where the temperature ranges from –1˚ to 3˚C (30.5˚ - 37.5˚F). Although
ocean water at these depths may reach temperatures below freezing, the water does not solidify.
The salts dissolved in the water interfere with the freezing process, allowing ocean water to
dip below the freezing point of pure water.
The Marine Environment Background
The Marine Environment
Pressure. Pressure is defined as force acting on an area. At sea level, there are 14.7 pounds
of air pushing on every square inch of your body (14.7 pounds per square inch or psi). Humans
are well adapted to live at this pressure. Under water, pressure increases at a constant rate of
14.7 psi every 10 meters. Greater depths mean greater pressure, since there is more water pushing
from all sides. Without special equipment, our bodies would collapse under this high pressure.
Corrosion. Corrosion occurs when a metal reacts with oxygen, typically in the presence of
water. For many metals, like aluminum, this corrosion leaves an unreactive layer on the surface,
which actually protects the metal from further reaction. Iron is an exception. Iron oxide (or rust)
flakes away from the metal, exposing the metal underneath to the same process. To make matters
worse, salts in the ocean water further accelerate the corrosion process. A protective coating
such as oil, porcelain or paint can be put over the metal to prevent corrosion, but this is good
only if the coating remains watertight at all points.
Natural History Museum of Los Angeles County
9
The Marine Environment
That Sinking Feeling pre-visit, post-visit
10
That Sinking Feeling
Students will make observations of liquids with different densities and
explore how this property is related to sinking, floating and ocean currents.
Introduction
A student has two similar cubes, one made of wood and one made of lead. Which has more mass?
Materials
1-2 liters of warm water
(w/ red food color)
1-2 liters warm salt water
(w/ yellow food color
and non-iodized salt)
1-2 liters cold water
(w/ green food color)
Because the lead is more dense, meaning it has more mass per volume, the lead cube would
have a greater mass. Density, which is related to how tightly packed particles are within a piece
of matter, is often a confusing concept, since its measurement depends on two factors, mass
and volume. An easy way to compare object densities is by checking to see whether they sink or
float. Objects that sink are more dense that the liquid they are in; objects that float are less dense.
Ocean water has different densities in different places. Warmer water is less dense than colder
water. But frozen water is less dense than liquid water. (Water is unusual in this way!) The amount
of salt can affect density, too. Saltier water is more dense than less salty water.
1-2 liters cold salt water
(w/ blue food color
and non-iodized salt)
blue ice cubes
(w/ blue food color)
clear glasses or beakers
plastic spoons
Note: Amounts will vary
depending on whether these
are presented as demonstrations
or group investigations.
Changes in the density of water caused by temperature and salinity (the amount of salt) are the
primary cause of ocean currents. Ocean water at the surface warms and evaporates, leaving salts
behind. This makes the water at the surface extra salty and more dense. As this water sinks to the
bottom, less salty water is pushed to the surface, where evaporation begins and the cycle continues.
Here are two short activities that will help students to understand some practical implications of
varying water density. These can be conducted as small group activities or class demonstrations,
followed by discussion.
Activity time
35 minutes (Part A)
15 minutes (Part B)
Process skills
Observing
Predicting
Ordering
Relating
Inferring
Connections
Physical Science
Math
Teacher Tip: If possible, use
non-iodized or kosher salt to
create the salt solutions.
Epsom salts work as well.
Use food coloring to color each
of the types of water—this will
make it easier to keep track
of which is which.
Natural History Museum of Los Angeles County
1. Give each student team containers of warm and cold fresh water, as well as warm and
cold salt water. Each team should also have several clear glasses or beakers and some
plastic spoons.
2. Challenge students to add the different waters to the beaker in such a way that four separate
layers can be seen. As students begin to develop and test their hypotheses, remind them
to keep notes of what works and what doesn’t. Students should wait to dump out their
“mistakes,” as their observations may help them to correct their initial guess.
3. Ask each team to report their findings (What order worked best?) and explain what this
tells them about the densities of these four liquids.
Additional questions for discussion:
What happens to salty water when it is added to fresh water?
How could water at the ocean surface become saltier than the water beneath it?
Do you think water in the ocean might get into separate layers by itself? How?
Teacher Tip: You might
show students how the liquids
can be added carefully to each
other (by spoonful, over the
back of a spoon, dripping it
down the side of the glass, etc.)
Investigation B: Ice Inquiry
1. Ask each student (or team) to fold a piece of paper into thirds and then write the following
headings: PREDICTION, EXPLANATION, OBSERVATION.
2. Give each student team a clear glass of warm water and then ask them to record (under
PREDICTION) what they think will happen if an ice cube of colored water was added to the
glass. Encourage students to be specific about what they will see. Once they’ve described
their prediction, they should then try to explain why they think this will happen and record
this under EXPLANATION.
3. Give each team a colored ice cube (food coloring in water, then frozen). Students should
carefully observe what actually happens for a few minutes after the cube is added, and
then record their findings under OBSERVATION.
That Sinking Feeling
Procedure
Investigation A : Salty, Fresh, Hot or Cold?
Helpful Hint: The correct
layering should be (from
bottom to top): cold salt
water, cold water, warm
salt water, warm water. Note
that depending on the
concentration of salt in the
solutions, the middle layers
(cold water and warm salt
water) may be reversed.
4. Discuss. Did the prediction match the observation? What information was the first
explanation based on? How might you change your explanation? How does density
figure into these observations? Explain to the students that currents in the ocean are
caused by moving water, sometimes pushed by wind, but mainly caused by differences
in density.
Extension
You might consider asking students to calculate the densities of the different solutions. Using
a balance and a measuring cup or graduated cylinder, students can measure mass and volume.
(When finding the mass of a liquid, remind students to subtract the mass of the empty container
from the measured mass of liquid and container.)
Mass is usually measured
in grams and volume in
milliliters. This results in a
unit of grams per milliliter
or g/mL for density.
Density =
Natural History Museum of Los Angeles County
Mass
Volume
11
Finding Your Way Background
12
Finding Your Way
How do we know where we are and where we’re going?
Background
Beginnings of Navigation
Almost anyone can travel without getting lost, as long as they know where they are, where
they want to go and the path between. On land, a person can use landmarks and physical
descriptions: “Take the path uphill to the big rock that looks like a bear. Find the three trees
growing from one stump and walk past it until you can see the waterfall.” This method doesn’t
work well on the ocean: “Turn left at the third wave, and go until you see the big fish with
the red stripes. Turn right and go until you reach England.”
The earliest sailors probably kept close to shore, using the land’s physical features as landmarks
to steer by. This worked well for short voyages, since food, water, and shelter were always
close by. Of course, this approach worked only when sailing during the day, and made for
very long trips. As sailors made maps of their travels, it became evident that some places
could be reached faster by sailing in a straight line, rather than hugging the shore. But this
would mean leaving sight of land and any recognizable landmarks.
Some of the early methods used for navigating across open waters involved using the sun,
moon, and stars. People had long been travelling on land, getting from place to place by
traveling in directions in some relationship to these celestial bodies. With the invention of
the compass, people could find their direction even when they couldn’t clearly see the sky,
day or night. These methods were applied to ocean travel; if a sailor knew another port was
west of his home port, all he had to do was follow the path of the sun or his compass.
Unfortunately, winds and currents further complicated this process, as they could easily and
subtly alter the heading and leave the traveler lost. Through generations of experience, many
early coastal cultures became familiar enough with their local currents and winds to actually
be able to navigate by them over moderate distances away from shore. Long distance voyages
and trips to little known areas, on the other hand, were still problems.
Natural History Museum of Los Angeles County
The concepts of longitude and latitude have
been used now for roughly 2000 years. Lines
of latitude run around the globe and measure
the degrees north or south of the equator. The
equator is given a value of zero (0). Lines of
longitude run up and down the globe and
measure the degrees east or west of a line
called the prime meridian, which passes through
the original location of the Royal Observatory
at Greenwich, near London, England. The
prime meridian is given the value of zero (0)
degrees. When the latitude and longitude are
given, the precise location of a point can be
located on an imaginary geographic grid. When
latitude and longitude are given on a map,
latitude is always written first. Degrees of
latitude and longitude are further divided into
minutes and seconds. There are sixty minutes
in one degree, and sixty seconds in one minute.
One of the earliest tools used to aid mariners
in determining latitude was the astrolabe. This
instrument consisted of a metal disk, graduated
in degrees, with a moveable sight. The astrolabe
was held vertical by a plumb bob, and the
navigator (with the help of two other people)
adjusted the sight until it was in line with a star.
The degree measurement was then looked
up on charts and tables, which gave the latitude
of the ship. Modifications of this instrument
by scientists, including Sir Isaac Newton, led
to the development of a new device called a
sextant. The basic design of the sextant has
remained virtually unchanged for over 200 years.
Determining longitude was a bit more difficult.
Many attempts were made at finding ways to
determine longitude while at sea, but none
were very successful. In 1735, John Harrison
developed the chronometer—an extremely
accurate timepiece that was used to maintain
a time reference to the prime meridian. This
instrument allowed navigators to compare
local time to time at the prime meridian. The
time difference between the navigator’s present
position and the prime meridian told them their
position. At last, a simple and reliable method
of determining longitude! It was now possible
to accurately determine position anywhere
on the ocean provided you had good charts
and tables, and an accurate chronometer. Sailors
navigated well into the 20th century using
these techniques until the advent of more
sophisticated electronic and radio methods.
New Technologies
Today, radio beacon towers are located all along
our coastlines, constantly sending out powerful
identification signals. These signals can be picked
up by sea vessels as far as several hundred miles
away. The Radio Direction Finder (or RDF) on
board a ship can be tuned to receive these
broadcast signals. The beacon’s I.D. signal, in
Morse code, allows the navigator to look on a
map and find the radio beacon that is sending
that particular signal. The RDF is also used to
determine the direction or heading from which
the signal is being sent. A second radio beacon
signal is then needed to pinpoint the exact
location of the vessel. This entire process is
known as triangulation. (See the activity
Getting Your Bearings for more information.)
Finding Your Way
Latitude and Longitude
The Global Positioning System (GPS) is a
satellite-based radio navigation system developed
in the 1970’s by the Department of Defense.
GPS allows land, sea and airborne users to
locate their three-dimensional position any time,
anywhere in the world. The GPS uses an
array of satellites continuously sending highfrequency radio signals; at any given time
from any point on earth, there are six or more
GPS satellites orbiting above you. GPS receivers,
many of which are smaller than a paperback
book, are used to pick up these signals. These
satellite signals contain information about the
exact position and clock reading on board. The
GPS unit compares the signal departure times
and arrival times, and the time delay is used to
calculate the distance between the satellite and
the receiver. The GPS determines the distances
from three or more satellites and uses this
information to find the closest possible location
of the user, usually within a few feet.
Natural History Museum of Los Angeles County
13
Finding Your Way
Map Building pre-visit
Materials
large wall map*
sets of activity pieces with
map coordinates*
tape
Map Building worksheets
Rulers (one per student)
*materials found in Seamobile Teaching Kit
Activity time
40 minutes
Process skills
Communicating
Comparing
Ordering
Connections
Math
Geography
Map Building
Students will develop their own map based on their knowledge of
latitude and longitude and discover the many things that make up
an ocean ecosystem.
Procedure
students should locate the proper positions
of their pieces on the map worksheet.
1. Review the concepts of geographic grids,
latitude, and longitude.
2. Explain to the students that over the years,
the Seamobile research area has been mapped
by many different people for different reasons.
Before we can study the area, one concise map
must be developed so that we know where
everything is. It will be the students’ jobs
to piece together the information from the
previous investigators.
5. Each team representative will place their
team’s map pieces on the wall map using
tape. In many cases, students can confirm
the location of their map piece by looking
on the large map for a similar symbol.
6. Discuss what their pieces represent and why
these various things are found in our oceans.
Extension
3. Divide students into teams and distribute one
set of four map pieces to each team. Each
piece represents an ocean feature (kelp forest,
shipwreck, sewage drain, etc.) In addition,
each team (or student) should receive a map
worksheet depicting the area surrounding
the San Pedro Channel.
4. Using the latitude and longitude coordinates
on the back of each individual map piece,
14
Many of the features described in this
activity have symbols which are used on
ocean maps. It is important to understand
that there is more than one symbol that
might be used for a feature, and that
some features may not be marked on a
particular map. The list of symbols on the
following page can be used to doublecheck latitude and longitude readings on
the wall map at the end of the Map
Building activity.
Natural History Museum of Los Angeles County
Natural History Museum of Los Angeles County
15
Map Building Student Worksheet
Based on NOAA chart 18740
Scale: 1:234,270
Seamobile Study Area
Common Nautical
Chart Symbols
Map Building Chart Symbols
16
Shipwreck
Sewer line
Radio beacon
Kelp bed
Oil/gas platform
Lighthouse
Fish haven
Dump site
Buoy
SOURCE: Chart No. 1, United States of America, Nautical Chart Symbols, Abbreviations and
Terms, 1990; Department of Commerce, National Oceanic and Atmospheric Administration;
and Department of Defense, Defense Mapping Agency.
Natural History Museum of Los Angeles County
Finding Your Way
Getting Your Bearings
In this activity, the Seamobile has scouted five possible study locations and has taken radio beacon
readings at each of these locations. Using triangulation, the students will plot the location of the
Seamobile and the five study sites. Then they will plot headings from the Seamobile to each location.
Procedure
1. Divide the class into teams of 3 or 4 and distribute materials to each team. Introduce the
concept of triangulation and discuss the use of radio beacons and corresponding compass
headings to determine location. Distribute the “Student Information Sheet” and data table
for this activity
2. Locate the Seamobile on the chart through triangulation. Use the given radio beacon (RB)
readings as compass headings to plot. For example, if radio beacon one (RB1) is 90, this
translates into a compass reading of 90 degrees. Follow the steps as described on the
Student Information sheet.
Materials
laminated desk map*
(one per team)
parallel ruler*
(one per team)
overhead marking pen*
(one per team)
Getting Your Bearings worksheet
*materials found in Seamobile Teaching Kit
Activity time
60 - 90 minutes
Process skills
Communicating
Comparing
Ordering
Connections
Geometry
Geography
3. It is helpful to work through the triangulation method for the Seamobile location
step-by-step with the entire class.
Teaching Tip: You may
4. Once students have identified the location of the Seamobile, they should proceed to identify
the locations of each of the study sites, using the radio beacon readings in the data table for
each site.
wish to use an overhead
transparency to help
demonstrate triangulation
to the entire class first.
5. After the study sites have been located, the students can determine the compass heading
from the Seamobile to each study site. Again, you should work through the first heading
(for site A) with the entire class. Follow the steps described in the Student Information sheet.
Teaching Tip: A quick
6. Remind the students that because they are using a circle of 360 degrees to define their
direction, they don’t need to add a direction indicator (like S or NE). These direction
designations are redundant for this method.
7. Ask students to double-check their locations by using the latitude and longitude readings
from the answer key.
Natural History Museum of Los Angeles County
check to see if students were
able to correctly identify the
location of the Seamobile is
to look for a nearby depth
reading of 204 fathoms on
their map. If the intersection
of the bearing lines is within
a quarter diameter of this
point, students are on the
right track!
Finding Your Bearings pre-visit
There are various ways to determine your position in the open ocean. One method is to use
a Radio Direction Finder (RDF). Radio signal transmitters (beacons) are located along coastlines
and send signals that can be picked up by the RDF device on ships at sea. The radio signal
can then be used to determine the compass bearing from the radio beacon to the ship. By
determining the bearings from two different radio beacons, navigators can determine their
ship’s position by examining where the bearing “lines” intersect. This method of pinpointing
the location of an object based on two different bearings is called triangulation.
Finding Your Way
Introduction
Getting Your Bearings pre-visit
Students will use rulers and an understanding of compass readings
to identify the location of five possible Seamobile study sites through
a process of triangulation. Students will then determine headings to
each of these sites.
17
Student Information Sheet
Getting Your Bearings
The triangulation process described below will help you find the location
of sites on ocean and help you figure out what direction you need to
travel to get there.
Getting Your Bearings Student Information Sheet
1
RB1
To locate a site:
1. Locate the two radio beacons (RB1
and RB2) and the compass rosette
on your map.
0
270
90
RB2
180
2. Begin by looking at one radio
beacon reading (RB1) and marking
the heading on the compass using
the overhead marking pen. Use the
parallel ruler to draw a straight line
connecting your heading mark and
the center of the compass.
2
RB1
0
270
90
RB2
180
3. Place the bottom edge of the parallel
ruler along the compass line you just
drew. While holding the bottom of
the ruler in place, move the top half
of the parallel ruler up until the ruler
edge touches the center point of
RB1. Use the marking pen to draw
a line on the map along the top
edge of the ruler. Be sure to hold
the ruler so that it does not slide.
4. Remove the ruler—you have just
recorded your first radio beacon
heading! This tells you that the
location is somewhere along that line.
To pinpoint the site even more, you’ll
need another heading (like RB2).
3
RB1
0
270
90
RB2
180
4
RB1
0
270
90
RB2
180
18
Natural History Museum of Los Angeles County
Student Information Sheet Continued
5a
RB1
0
270
90
RB2
180
6. Circle the point of intersection and
label it. Repeat these steps to find
the other sites.
5b
RB1
0
To find the heading:
7. Place the top edge of the parallel
ruler so that it connects the Seamobile
location (SM) and a study site. While
holding the top part of the ruler in
place, lower the bottom half of the
ruler edge until it touches the center
of the compass rosette. Draw a line
along the lower edge of the ruler,
passing through both sides of the
compass rosette.
270
90
RB2
180
6
RB1
SM
ø
0
8. To choose the correct compass reading,
look at the direction you would take
to get to the site from SM. If you are
heading north, choose the compass
reading on the north (top) side of the
compass; if you are heading south,
choose the south (bottom) reading.
Record your heading on the data sheet.
270
Getting Your Bearings Student Information Sheet
5. Repeat steps 2 through 4 for RB2.
The line you draw in step 4 this
time should intersect the first line.
If not, try these steps again.
90
RB2
180
9. Repeat these steps to find headings
for the other sites.
Natural History Museum of Los Angeles County
19
Student Data Sheet Getting Your Bearings
Record the headings for each site.
Getting Your Bearings Student Data Sheet
SITE
RB1
RB2
Seamobile
79º
212º
site A
72º
130º
site B
118º
200º
site C
340º
240º
site D
80º
124º
site E
110º
173º
Heading to
site from
Seamobile
Mark the approximate location of
each study site on the map below.
eles
g
n
A
Los
es
erd
V
os
Pal
h
eac
B
g
Lon
ch
Bea
t
r
po
New
RB1
San
Ped
ro C
han
nel
Cat
alin
a Is
lan
d
20
RB2
Natural History Museum of Los Angeles County
SITE
RB1
RB2
Seamobile
79º
212º
site A
72º
130º
site B
118º
site C
Heading to
site from
Seamobile
latitude
longitude
33º 32’
118º 12’
245º
33º 26’
118º 27’
200º
10º
33º 42’
118º 10’
340º
240º
83º
33º 34’
118º 52’
site D
80º
124º
262º
33º 29’
118º 35’
site E
110º
173º
322º
33º 44’
118º 23’
Natural History Museum of Los Angeles County
Getting Your Bearings Answer Key
Answer Key Getting Your Bearings
21
Finding Your Way How Far? How Long? pre-visit
How Far? How Long? pre-visit
Finding Your Way
How Far? How Long?
22
Students will determine how far their ROV has to travel from the
Seamobile to their study site, and how long it will take to reach the site.
Introduction
On the Seamobile, students send their ROVs (Remotely Operated Vehicles) out to their study
sites to collect data. In this activity students will determine, using maps and rulers, how far away
the site really is. Using these measurements, they will also calculate how long it would take an
actual ROV to reach the destination.
Materials
laminated desk map with location of
Seamobile and study sites marked*
(one per team)
ruler with inch markings
(one per team)
How Far? Worksheet
(one per student)
*materials found in Seamobile Teaching Kit
Activity time
30-40 minutes
Process skills
Communicating
Relating
Connections
Procedure
1. This activity works well as a follow-up to the Getting Your Bearings activity, where the study
sites have already been located and marked on the maps by the students. You can also
begin by asking students to find the study sites by using latitude and longitude readings,
as provided in the answer key for Getting Your Bearings.
2. Distribute materials and student worksheet.
3. Once distance has been measured and converted (1 inch = 3 Nautical miles), students should
determine how long an ROV traveling at 4 knots (4 nautical miles per hour) would take to
get there.
4. A more familiar measurement of speed for students may be miles per hour. To convert knots
into miles per hour, multiply the number of knots by 1.15 (knots x 1.15 = miles per hour).
You could also have the then convert miles per hour to Kilometers per hour, which is the
measurement of speed that most modern scientists use (1 mph = 1.6 Kph).
Algebra
Helpful Hint: One nautical
Sample calculation:
mile equals 6076 feet, while
one standard mile equals
5280 feet. Nautical miles are
the distance of one minute
of arc on the Earth’s surface.
There are 60 nautical miles
in each degree of latitude.
If your site is 6 inches away from
the Seamobile on the map:
Teaching Tip: For students
completing the activity using
their triangulation results, you
can probably expect an error of
± 0.5 hours for the calculated
travel times since results will
be based on the accuracy of
the original triangulation.
You might consider using the
distances in inches from the
key and go from there.
18 nautical miles
= 4.5 hours
4 nautical miles/hour
(travel time to site)
6 inches x 3 nautical miles/inch = 18 nautical miles
(distance to site)
Natural History Museum of Los Angeles County
Student Worksheet How Far? How Long?
Answer the following questions.
Be sure to show how you got the answer.
1.What is the distance (in nautical miles)
from the Seamobile to your study site?
Useful Conversions:
2. What will be the travel time (in
hours) for the ROV to get to your
study site if it travels at a speed of
4 knots (nautical miles per hour)?
1 inch = 3 nautical miles
(for the large desk maps)
1 knot = 1.15 m.p.h.
1 nautical mile = 1.15 miles
1 m.p.h. = 1.6 km per hour
Formulas:
3. What is the speed of the ROV
in miles per hour (m.p.h.)?
Speed = Distance
Time
Time =
Distance
Speed
Distance = Time x Speed
How Far? How Long? Student Worksheet
Now that you have located your study site, you will need to
determine how far the it is from the Seamobile, and how long it
will take your Remotely Operated Vehicle (ROV) to travel from
the Seamobile to the study site.
4. What is the speed of the ROV in
kilometers per hour (Km/hr)?
5. What is the distance in “land miles”
from the Seamobile to your study site?
Natural History Museum of Los Angeles County
23
Answer Key How Far? How Long?
How Far? How Long? Answer Key
How Far? How Long? Teacher Key
Site
Letter
Map Distance
(in Inches)
Distance
(nautical miles)
Distance
(land miles)
Travel Time
for ROV
A
4.5 inches
13.5 Nm
15.5 miles
3.4 hours
B
3.5 inches
10.5 Nm
12 miles
2.6 hours
C
5.25 inches
15.75 Nm
17.9 miles
3.9 hours
D
6 inches
18 Nm
20.7 miles
4.5 hours
E
4.75 inches
14.25 Nm
16.4 miles
3.6 hours
ROV SPEED
24
knots
miles per
hour
Kilometers
per hour
4
4.6
7.4
Natural History Museum of Los Angeles County
Classifying Creatures
How can we identify plants and animals based on physical characteristics?
Below is an example of how scientists
classify the striped dolphin, showing
the pattern of groups within groups
more general
KINGDOM: Animalia
Cell structure
differentiates animals
from other types of
living things such as
plants and bacteria.
PHYLUM: Chordata
The animal has
a spinal chord.
SUBPHYLUM: Vertebrata
CLASS: Mammalia
ORDER: Cetacea
FAMILY: Delphinidae
The spinal chord has
backbones, or vertebrae,
protecting it.
These vertebrates have hair
and females produce milk to
feed their young.
These marine mammals have
front flippers and a dorsal fin,
but no hind limbs.
Members of the dolphin family
include all oceanic dolphins. Size
and details of skull and tooth
shape distinguish delphinids from
other cetaceans.
GENUS: Stenella
SPECIES: coeruleoalba
A system of binomial nomenclature,
accepted by scientists worldwide, assigns
two Latin names for each organism. The
first name is the genus name, given to
groups of closely related species. The
second part is the species name, given to
a group of organisms that can interbreed
and produce more organisms. This system
is similar to a person having a first and last
name. Therefore, using the example above,
scientists know the striped dolphin as
Stenella coeruleoalba, or S. coeruleoalba,
for short. When the organism’s scientific
name is written, the genus name is always
capitalized and written first and both words
are always italicized.
Many organisms have common names.
But sometimes things can get confusing
when people from different regions use
different names. For example, what one
scientist calls the Striped, another might
call the Whitebelly dolphin, however, if
the name Stenella coeruleoalba were used,
both people would understand which
species of dolphin they were discussing.
Development of a common classification
system allows scientists all over the world
to work together more easily as they
decode nature’s secrets.
more specific
Natural History Museum of Los Angeles County
25
Classifying Creatures Background
In order to better describe nature, biologists have developed a way of classifying living things
into groups. These groups, and groups within groups, arrange organisms according to similarities
and can help us understand how species may have evolved. This taxonomy of groups ranges
from the most general (kingdom) to the most specific (species).
Classifying Creatures Background
Background
Odds and Ends
Students are introduced to a common method of classification used by
scientists-the dichotomous key. They will use this method to “identify”
a collection of everyday objects.
Introduction
Classifying Creatures
Dichotomy:
Division into two parts,
groups or classes.
Scientists use keys to help identify and classify plants and animals. By organizing specimens
based on similar characteristics, scientists can better understand how these species might be
related to each other on an evolutionary level. Keys can come in many different formats—
some are used to identify organisms into larger categories, such as kingdoms or phyla, and
others are used to distinguish among closely related species.
A dichotomous key presents the user with a series of positive/negative statements relating
to distinct characteristics of the specimen. (“The animal has a backbone.”, “The animal does
not have a backbone.”) These statements are sometimes referred to as couplets. Notice that
the couplet is essentially an either/or choice. The specimen is correctly identified when one
makes the appropriate choice for each set of characteristics in a series of consecutive steps,
similar to a flow chart.
Odds and Ends pre-visit
Materials
Bag of odds and ends*
(one per team)
(Each bag of odds and ends contains: small metal paperclip, large
metal paperclip, plastic coated
paperclip, wooden clothespin
(w/out metal spring), party toothpick
w/ plastic fringe, small sponge,
metal jack (colored), rubber garden
hose washer, penny, plastic straw
(cut to 3”), pencil-top eraser)
This activity introduces students to the use of a dichotomous key using everyday items. The
goal of this activity is NOT to try to identify these objects, but rather to use a key correctly.
Procedure
Discuss with students different ways of grouping objects. Ask why it is important to group objects.
You might Introduce dichotomous keys as one way of grouping and identifying things. Introduce
the term “dichotomy” and show how this is important in this kind of classification scheme.
Example: The people in this room could first be grouped into categories of eye color. One
couplet for this might be:
People who have brown eyes.
People who don’t have brown eyes.
Odds and Ends worksheet
*materials found in Seamobile Teaching Kit
Activity time
30 minutes
Process skills
Comparing
Ordering
Categorizing
2. Divide the students into teams of two or three and give each team a bag of odds and
ends and the worksheet Odds and Ends.
3. Students should choose one item from the bag and follow the key in order to “identify”
the object. After making the appropriate choice in each couplet, the team will then follow
the directions on the right hand side of the key until they have identified the object with a
particular letter. Students can write the object name next to the appropriate letter on their
worksheet, or copy this information into a notebook.
Teaching Tip: Students
often “switch” their items as
they proceed through the key,
choosing an item that matches
the positive statement. That
is, a student classifying a
paperclip, after the statement
“Object not made of metal”,
might drop the paperclip and
pick up a toothpick, since it
makes that statement true. Ask
students to close their bag
after choosing an item. The
bag should remain closed until
the group has completely
finished identifying that object.
26
Natural History Museum of Los Angeles County
Student Worksheet Odds and Ends
For this activity, you will use a dichotomous key
to sort some everyday objects.
1. Choose one item to start with.
2. Begin by reading the first set of choices, called a couplet.
After discussing the two choices within the first couplet with your team, decide which
statement in the pair most closely describes the item you are trying to identify.
3. Next, follow the directions on the right hand side of the key.
For example, in couplet number 1 if you decide that the object was metal,
you would continue on to couplet number 7;
if you decide that the object is not metal, you would continue on to couplet number 2.
4. Continue to work until your team has identified all 11 objects.
5. After you have identified all the objects, check your answers with the teacher’s answer sheet.
choices
1. Object made of metal
Object not made of metal
directions
Go to couplet 7
Go to couplet 2
2. Wood
Not wood
Go to 3
Go to 4
3. Plastic tip
No plastic tip
Object a
Object b
4. Rubber
Not rubber
Go to 5
Go to 6
5. Pointed
Not pointed
Object c
Object d
6. Rectangular shape
Tube shape
Object e
Object f
7. Painted
Not painted
Go to 8
Go to 9
8. Flat
Not flat
Object g
Object h
9. Object copper color
Object silver color
Object i
Go to 10
10. Greater than 3 cm
Less than 3 cm
Object j
Object k
Natural History Museum of Los Angeles County
Odds and Ends Student Worksheet
How to Use This Key
27
Odds and Ends Answer Key
Odds and Ends Answer Key
28
Answer Key Odds and Ends
Object
Object
Object
Object
Object
Object
Object
Object
Object
Object
Object
a
b
c
d
e
f
g
h
i
j
k
tooth pick
clothes pin
eraser
rubber washer
sponge
plastic straw
painted paper clip
jack
penny
large paper clip
small paper clip
Natural History Museum of Los Angeles County
A Key to California Marine Shells
Students will use a dichotomous key to identify
a collection of shells from local marine animals.
2. Give each team of students a set of unidentified marine shells, from the Teaching Kit.
3. The student worksheet describes how the key should be used. When students have finished
identifying the shells, they may check their answers on the answer sheet provided.
Materials
Set of marine shells*
(one per student team)
Extension
Ask students to create a simple diagram that shows how they grouped the shells.
Remind the students to describe the characteristics at each branch point.
(See sample below.)
A Key to California Marine Shells
worksheet
*materials found in Seamobile Teaching Kit
Activity time
30 minutes
Process skills
Observing
Comparing
Ordering
Categorizing
shells
two parts
?
one continuous part
round or
circular
clam
Natural History Museum of Los Angeles County
?
?
Classifuying Creatures
1. Divide the students into teams of two or three.
A Key to California Marine Shells pre-visit
Procedure
29
Student Worksheet
A Key to California Marine Shells
This dichotomous key will allow you to identify 8 shells from southern
California. Follow the directions below to correctly identify each species.
A Key to California Marine Shells Student Worksheet
30
How to Use This Key
1. Choose one shell to start with.
2. Begin with the first set of choices, called a couplet.
3. After discussing the two choices in the first couplet with your
partner, decide which characteristics in the pair most closely
resemble the shell you are identifying.
4. Next, follow the directions on the right hand side of the key.
For example, in couplet number 1 if you choose that “the shell
has one part”, you would continue on to couplet number 3; if
you choose that “the shell has two parts”, you would continue
on to couplet number 2.
5. After you have identified each shell, check your answers on
the answer key.
Pair
Couplets
Directions
1.
Shell has two hinged parts
Shell has one continuous part
Go to couplet 2
Go to couplet 3
2.
Each shell is teardrop shaped or oblong
Each shell is round or circular
Mussel
Clam
3.
Shell has one hole or opening
Shell has more than one opening
4
7
4.
Shell is 6 cm or smaller
Shell is 6 cm or larger
5
6
5.
Shell is purple-gray
Shell is brown-orange
Olive snail
Chestnut cowry
6.
Total length of shell is 8 cm or smaller
Total length of shell is 8 cm or larger
Wavy top turban snail
Kellet’s whelk
7.
Shell has four or more small holes on top
Shell does not have four or more small holes on top
Abalone
Keyhole limpet
Natural History Museum of Los Angeles County
Mussel
clam
olive snail
chestnut cowry
(olivella)
Kellet’s whelk
abalone
Natural History Museum of Los Angeles County
keyhole limpet
A Key to California Marine Shells Answer Key
Answer Key A Key to California Marine Shells
wavy top turban snail
31
Invent A Key for Echinoderms
Students will make observations and use their understanding of classification
to create a dichotomous key which will help distinguish several echinoderms.
Introduction
Echinoderm is taken from a Latin term that means “spiny skin.” These animals live underwater
and include sea stars, sand dollars, sea cucumbers, sea urchins and brittle stars.
Classifying Creatures
Procedure
Invent a Key for Echinoderms pre-visit
32
1. If you have not already completed the activity Odds and Ends, consider using some
of the same introductory discussion recommended for that activity.
2. Divide the class into teams of 2 to 4. Give each group an Echinoderm Photo set
and a worksheet.
3. Students can begin by examining the cards and thinking about different characteristics
they might use to group the objects (body shape, color, number of arms, etc.)
Materials
Set of 8 Echinoderm Photos*
(one per team)
Invent a Key worksheet
*materials found in Seamobile Teaching Kit
Activity time
40 minutes
Process skills
Observing
Communicating
Comparing
Ordering
Categorizing
4. Once the students have had a chance to think about grouping, ask teams to devise
a dichotomous key for their echinoderms on the worksheet provided. Remind them
that they will write couplets, which basically provide a choice between two options.
Example: Animal has a shell.
Animal does not have a shell.
6. Encourage students to follow one branch of classification to its completion,
rather than looking back at the whole set of photos all at one time.
7. Once students have completed their key, ask each team to present their classification
scheme to the class. As they describe their choices, ask other students to consider
how their dichotomous key was different. Alternatively, you may ask groups to
exchange keys and see if they can classify the pictures using the other team’s key.
Alternative assignment
Some students may be able to organize their key better in a more graphic mode.
Consider asking students to choose which mode (written text or branching diagram)
they prefer. If students choose to create a branching diagram, remind them to describe
the characteristics at each branch point.
Teaching Tip: A master set
of echinoderm photos is also
available at the end of this
guide. These may be scanned
or copied to produce
transparencies or extra sets,
especially if the Seamobile
Teaching Kits are unavailable.
Teaching Tip: There is no
one right answer for this
activity. Each group will
interpret their observations
differently. Assessment
should be based on student
explanation and the
effectiveness of their choice
of couplets.
Extensions
1. After students have created their own keys, you might share with them the actual names
of these echinoderms. Notice that some are actually the same species, even though they
look quite different.
species
A
B
C
D
E
F
G
H
common name
purple sea urchin
bat star
sunflower star
brittle star
brittle star
sea star
sea cucumber
sea cucumber
scientific name
(Strongylocentrotus purpuratus)
(Patiria miniata)
(Pycnopodia helianthoides)
(Ophiothrix spiculata)
(Ophioderma panamense)
(Pisaster giganteus)
(Paristichopus parvimensis)
(Paristichopus parvimensis)
2. Ask students to create a classification system for more common “species” such
as snack foods, writing utensils or types of shoes worn by students in the class.
Natural History Museum of Los Angeles County
Student Worksheet Invent a Key for Echinoderms
Use the spaces below to write couplets which group the
echinoderms (on the picture cards) into smaller categories.
2.
3.
4.
5.
6.
7.
Invent a Key for Echinoderms Student Worksheet
1.
8.
Natural History Museum of Los Angeles County
33
Life Beneath The Waves
How do plants and animals survive in these watery environments?
Background
Life Beneath the Waves Background
34
The oceans are the largest repositories of life on the planet, ranging from the largest whales
and sharks to the tiniest plankton and bacteria. Although there are a greater number of species
of animals living on land (due primarily to the vast number of insect species), the diversity of life
is much greater in the oceans compared to the land. In fact, 14 of the 32 animal phyla identified
by scientists are exclusively marine!
Marine Adaptations
Just like land plants and animals, marine plants and animals have adaptations such as specialized
body parts and unique behaviors that help them to survive (and procreate) within their
environment. When a plant or animal is adapted to its environment, it has characteristics that
help it survive in its environment. When looking closely at adaptations we study characteristics
such as the mouthparts, shape, color, methods of
locomotion and defense strategies. Furthermore,
just as plants and animals living on land are found in
a wide variety of habitats such as desert, forest or
mountain, marine animals are likewise adapted to a
wide variety of ocean habitats, such as kelp forest,
continental shelf, and rocky bottom. The following
sections compare three of these habitats: the kelp
forest, the sandy bottom, and the abyssal plane.
Natural History Museum of Los Angeles County
is the kelp forest. These undersea forests, typically
found in cooler waters at depths less than 120 feet,
are home to over 800 different marine species, all of
which depend on the kelp to provide shelter, food and
protection. Marine organisms populate the kelp forest
from holdfast at the bottom all the way to the water
surface, just as organisms in a rainforest populate that
habitat from forest floor to canopy.
found in the shallow coastal waters from the shore
to the edge of the continental shelf. The sand swept
from the shore by ocean currents makes vast stretches
of these underwater deserts. These somewhat
featureless habitats do not provide much shelter or
protection for their inhabitants, and many creatures
there protect themselves by burrowing in the soft
sandy seabed.
When looking at some of the fish in this habitat, we
can see similar coloration patterns. Some of the fish
may have stripes, such as the salema, and others may
have spots, like the kelp bass. Markings like these
that tend to break up the outline of the individual
or to make other easily recognizable features less
prominent and less recognizable to predators are
called disruptive coloration.
Despite the lack of shelter, many animals have adapted
to this desert-like habitat. The California halibut is
an example of an animal well adapted to the sandy
bottom habitat. The mottled, spotty brown coloration
of these flatfish allows them to blend quite well with
the sandy floor. Having their eyes on one side of their
head also helps the California halibut spot predators
more easily. The eelpout is another animal that has
adapted to living on the sandy bottom. This fish
protects itself from predators by burrowing deep into
the sand, leaving only its head exposed.
Other animals, such as kelpfish, use camouflage to
protect themselves. The body of a kelpfish looks
almost exactly like a blade of kelp, in both shape and
color. Juveniles can change color quickly from green
to brown. Adult males are usually a brown or olive
green color. The patterns on their bodies also imitate
the dark and light patterns of the kelp blades. Kelpfish
behavior is also a part of their adaptation. They hang
in the water next to the stipe amid the kelp blades,
oriented in the same direction as the blades, and move
their bodies in the same rhythm as the blades do as
they sway in the water.
The kelp itself has several adaptations for living in its
environment. Air bladders, small gas-filled sacs along
the stipe (or stem), help to hold the kelp blades up
in the water, allowing for maximum sun exposure. The
blades are the only part of the structure that are able
to create nutrients for the plant using photosynthesis.
The kelp also has an anchoring structure called a
holdfast. The holdfast is not a tangle of roots, but a
series of finger-like projections whose only job is to
grip the bottom substrate by tangling around the
rocks, so that the kelp does not float away.
Natural History Museum of Los Angeles County
Abyssal Plane. The ocean below 3,300 ft is
completely dark and extremely cold with a pressure
almost 100 times greater than the pressure at sea
level. Who or what could survive in such a harsh
environment? Although this habitat is less studied due
to the extreme conditions, scientists have observed
many amazing animal adaptations in the abyss.
Life Beneath the Waves
Kelp Forest. One of richest ecosystems on Earth Sandy Bottom. The sandy bottom habitat can be
In a place with no light, there can be no plants. So
unlike other marine habitats, the bottom of the food
chain consists exclusively of detritus, particles from
decaying plants or animals and animal waste falling
from shallower waters. Another unique feature of
this deep-sea habitat is an unusual adaptation shared
by many of the animals—bioluminescence, or the
ability to produce light. Scientists suspect that the
light generated by these organisms is used for finding
food, mates, and/or protection. Animals such as the
anglerfish have a long “fishing pole” structure with
a bioluminescent tip (called an esca) that dangles above
their mouth. This feature helps lure the anglerfish’s
dinner. The bioluminescence is also vital to the
reproduction of many of these deep sea animals,
often using the light to identify potential mates.
35
Squid Dissection: From Pen to Ink
Through squid dissection, students will examine some of the unique
features which have allowed squid to adapt and thrive in Southern
California waters and throughout the world. Students will identify the
internal and external anatomy of the squid. To avoid being wasteful,
the activity ends with a Calamari Cookoff!
Life Beneath the Waves
Squid Dissection: From Pen to Ink post-visit
36
Introduction
One of the main objectives of this activity is to introduce students to dissection, an important
part of science discovery that can help us better understand how life works. It is important for
students to see the role that dissection plays and develop a sense of responsibility and respect
for the animal that they are using as a learning tool.
After the students finish their dissection, the impact of squid in their daily lives should be discussed.
Squid are an important food item to many people throughout the world. With this in mind, the
students have the opportunity to prepare and cook their squid at the end of the lesson.
Materials for dissection
fresh or frozen whole squid
(Loligo opalescens) available at
a fish market or grocery store
(one per student or team)
clean dissection scissors
or basic student scissors
(one per student or team)
paper plates
paper towels
newspapers
Squid Anatomy worksheets
Materials for
food preparation
portable fryer and oil
containers for milk and flour
mallet (for tenderizing)
seasoned flour (such as Dixie Fry)
buttermilk
cocktail sauce (optional)
Activity time
40-50 minutes
Process skills
Observing
Communicating
Comparing
Relating
Teaching Tip: Depending
Dissection Procedure
1. Begin the activity by asking students what they know about squid. Encourage questions,
possibly making a list on the board that you may be able to answer as you continue through
the dissection.
Possible questions (relating to anatomy) might include:
How does it eat? What does it eat?
How does it swim? How does it “steer”?
How does it protect itself?
Is it male or female? How can you tell?
Consider giving students a copy of the information sheet, About Squid.
2. Using one squid for demonstration, and the worksheet Squid: External Anatomy, begin to
discuss the external anatomy and relate the features to the way the squid functions in its marine
environment. Important features include the arms and tentacles, for hunting and mobility;
the fins, for stabilizing and turning the squid while swimming; and the chromatophores,
which can change color to aid in finding a mate, or in warning other squid.
3. Provide each student, or pair of students, with a squid on a paper plate. Use newspapers
to cover the area where they are working.
4. Ask students identify the external anatomy of the squid. Make sure they count the number
of arms and tentacles. Have the students pull back the arms to locate the beak. As they
identify the features, they can fill in the spaces on their external anatomy worksheet.
5. After the students have had the opportunity to explore the external anatomy, they are ready
to begin the dissection. Instruct the students to position the squid on the plate with the
siphon facing up.
6. Distribute scissors. (These are the easiest tools to work with; scalpels are not necessary and
can be dangerous.) Ask students to make one long cut from the bottom of the mantle, above
the siphon, to the tip of the mantle next to the fins. Be sure to instruct the students to lift
up with their scissors when cutting so as not to cut into the internal organs of the squid.
on the class, you may wish
to demonstrate the entire
dissection for the class before
asking them to do it. A video
camera or flexcam attached to
a monitor could make this
even more effective.
Natural History Museum of Los Angeles County
8. When the students have located all of the internal organs, they can remove the arms and
internal organs from the mantle. Students should pick up the squid by the arms and while
holding the mantle in the other hand, pull to separate the arms from the mantle. If done
properly, the arms and internal organs will all come off in one piece. Students may notice
a thin shell-like pen inside the mantle. They can pull the pen out of the mantle. (They may
need to snip it out using scissors.)
9. While the students are dissecting the squid, consider asking
some questions to encourage discussion about the squid.
Where does the squid fit into the marine food web?
What adaptations does the squid have that allow it to survive?
Can you think of other animals that play a similar role in other ecosystems?
Have you ever used a squid for food or as fish bait?
Calimari Cook-Off
10. Have the students remove the fins by grasping the mantle in one hand and the fins in
the other and pulling to remove the fins. Then have the students clean the mantle by
removing any of the excess skin.
11. When the mantle is clean, have the students cut the mantle into strips. Once the strips
are cut, have the students tenderize the squid by pounding it a few times with a clean
block or meat hammer.
Squid Dissection: From Pen to Ink
7. Spread the mantle open and have the students identify the internal anatomy using the
Squid: Internal Anatomy worksheet. Begin with locating the feathery gills and following
those to their base to locate the hearts. Challenge students to find the liver, ink sac, and siphon.
12. The students should first coat the squid strips with buttermilk, and then roll them in the
seasoned flour mix. The teacher can then drop them carefully into the preheated deepfryer, and let them cook until they curl up and float to the top of the oil, approximately 1
minute. The cooking should be done by an adult to prevent burns or other injuries.
13. Garnish with cocktail sauce and enjoy!
Natural History Museum of Los Angeles County
37
External Anatomy Squid Dissection
FIN
These help squid change
direction when swimming.
Squid Dissection: From Pen to Ink
External Anatomy
38
CHROMATOPHORES
These spots change size
to change the squid’s
color for camouflage or
possibly communication.
MANTLE
This is the main part of
the squid’s body—all of
the organs are inside.
PEN
EYE
Squid have well developed
eyes that allow them to see
almost as well as people!
The squid is related to other
“shelled” animals like clams
and snails. The pen is all
that is left of the shell the
squid’s ancestors once had.
SUCTION CUPS
ARM
The suction cups help the
squid to hold onto food.
Squid have 8 arms
covered suction cups.
TENTACLE
The tentacles are
longer than the arms
and have suction cups
only at the tips. These
are used to pass food
to the shorter arms and
then to the mouth.
Natural History Museum of Los Angeles County
Squid Dissection: From Pen to Ink Student Worksheet
Student Worksheet Squid Dissection: External Anatomy
Natural History Museum of Los Angeles County
39
Internal Anatomy Squid Dissection
NIDAMENTAL GLAND
Squid Dissection: From Pen to Ink Internal Anatomy
40
This is a female reproductive
organ. It provides a protective
coating for the eggs.
CECUM
This is part of the
digestive system.
Processed food is
absorbed into the
blood here.
GILLS
HEARTS
These are used for
blood circulation.
LIVER
This helps
with digestion.
These are used
to absorb oxygen
from the water.
INK SAC
The squid releases
ink from this gland
in times of danger,
which is then pushed
through the siphon.
SIPHON
This tube squirts out
water so that the squid
moves like a jet airplane.
BRAIN
BEAK
The squid’s brain is
highly developed
for an invertebrate.
The squid mouth parts
resemble a bird’s beak!
Natural History Museum of Los Angeles County
Squid Dissection: From Pen to Ink Student Worksheet
Student Worksheet Squid Dissection: Internal Anatomy
Natural History Museum of Los Angeles County
41
About Squid
Quick Info:
About Squid
The squid is one of the most highly
developed invertebrates. Some of the
animal’s structures illustrate the
ways in which the squid has adapted
to life in the ocean. Its streamlined
body and “jet propulsion” which occurs
as the squid squeezes water out of its
body through its siphon, make the squid
a fast, active predator. This animal also
has a very good defense mechanism.
Squid have ten arms, which are
wrapped around the head.
Eight are short and heavy, and
lined with suction cups. The
ninth and tenth are twice the
length of the others, and are
called tentacles. Suction cups
are only on the flat pads at the
end of the tentacles.
All mollusks have a soft body
with a special covering called
the mantle, which encloses
all of the body organs such
as heart, stomach and gills.
Squid are an important part of
the ocean food web. Squid are
gaining popularity as a food
source for humans around the
world. Overfishing is a growing
concern because there are no
regulations on squid harvesting.
Squid produce a dark ink that they
use to escape from predators. When
a squid is startled, the ink is released
through the anus, and the cloud
of inky water confuses the predator
while the squid swims away.
Southern California squid
populations spawn mainly in the
winter (December to March).
Squid are seined (netted)
commercially at their spawning
grounds. About 6,000 metric
tons are taken yearly for human
food and bait.
42
Squid can be as small as a
thumbnail, or as large as a house.
The giant squid, Architeuthis,
can measure 60 ft. in length
and weigh three tons!
Squid feed on small crustaceans,
fish, marine worms, and even
their own kind! They use their
tentacles to quickly catch their
prey, which is pulled in by the
arms and down to the radula, or
beak, which uses a tongue-like
action to get food to the mouth
so it can be swallowed whole.
Squid are a major
food source for many
fishes, birds and
marine mammals.
After mating, a female squid
will produce 10-50 elongated
egg strings, which contain
hundreds of eggs each. In
many species, the parents will
soon die after leaving the
spawning ground. The egg
strings are attached to the
ocean floor, are left to develop
on their own, and hatch
approximately ten days later.
Natural History Museum of Los Angeles County
How can scientific data help us better understand
what is happening in a marine habitat?
Background
What are transects and what can they tell us?
Transects are simple ways of estimating population density, or the number of organisms living
in a given area. There are various methods of conducting transects (such as random sampling
and line transects), but they all follow a similar pattern. First, a small representative section of
the study area is chosen. Then, smaller sample areas, referred to as plots, are established. In a
line transect, these plots could be either touching or intersecting the line. The shapes of the plots
are usually circles or squares of equal size. Each plot is then examined, and the numbers of
individuals of the target species are counted. The total numbers for all plots are then averaged,
giving you an average density for the area of your plot. This can then be used to determine
the average population density of your entire target area.
What does population density tell us about habitat health?
In general, an increase in population density of a given species indicates that the area is favorable
to that particular species. If the density of all organisms increases, or remains stable over time,
this would indicate a relatively healthy habitat—one that is able to maintain a large population.
However, an increase of one population with decreases in others may indicate problems with
the habitat. It may indicate that one species is intensely predatory on other species, or that changes
in the habitat favor one species over another. If all species populations decrease over time, this
would tend to indicate major problems with the habitat. These problems could be natural, such
as a depletion of resources due to overpopulation or disease breakout in the area. Of course,
the problems also could be man made, such as pollution or overharvesting.
Making Sense of It All Background
Making Sense of It All
How can we interpret the data?
There are many difficulties in interpreting species density data, especially with animals. The major
problem is that, in most cases, animals tend to move. The assumption is that they will move into
or out of other plots, and the average will remain pretty much the same. The fact is, though, that
animals rarely move in a uniform manner, and the numbers may vary greatly from sample to
sample. Two ways researchers can try to account for this error are (1) using large area sample plots,
and/or (2) using many plots along the transect. This way, moving animals will be more likely to
stay in a sample area, or move into another sample area.
Seasons must also to be taken into account, since many organisms will show natural seasonal
fluctuations. Samples taken in spring may have completely different numbers from those taken
in late summer. Other issues that could confuse the interpretation of these data would include
natural population changes due to predators and disease, or predation by migratory species.
Miscounting or misidentification of species could also drastically alter the totals. The best way to
solve most of these difficulties is to take many frequent samples. Yet, this introduces new difficulties;
namely lack of time, money, and experienced researchers.
Natural History Museum of Los Angeles County
43
NOTE: THIS ACTIVITY SHOULD ONLY BE
CONDUCTED AFTER THE SEAMOBILE VISIT!
Completing the Seamobile Investigation
Students can complete their Seamobile Investigation by making a hypothesis
using the data they have collected and supplemental information.
Making Sense of It All
Introduction
Completing the Seamobile Investigation post-visit
44
This activity is designed to allow students to complete the Seamobile investigation following their
visit to the truck. As the program is designed for a range of student grades and abilities, there
are occasions when student teams are unable to complete the entire Seamobile program in the
allotted time. This activity provides the necessary background (for students and teachers) for
students to complete their investigation.
Materials
Data Summaries handout
(at least one per team)
Research Questions worksheet
(optional)
In the Seamobile, student teams collect data from one of five different study sites. A computer
database provides details for some of the key species at their each site. Once they’ve learned
about these key species, they examine video still frames of their study site to count the animals
or plants found in the area. They then compare this data to previous data collected ten years
before. In most cases, students discover that the numbers are different compared to ten years
ago. Students are asked to think about what might be causing these numbers to change over
time. The mission ends with the students making a hypotheses relating to the changes in species
populations, based on what they’ve seen and the data collected.
Activity time
Procedure
varies
1. Because each student team works at a different
pace, some teams will be further along (or
finished) compared to others. First establish
where the students are in the investigation.
This will give you an idea of how much more
time you will need to complete the program.
Process skills
Communicating
Relating
Inferring
2. Distribute the Data Summary page
appropriate for each group’s study site.
(All groups do not need information from
all sites.) Encourage students to read
through this information and think about
what this data tells them about their site.
3. In some cases, the species count taken by
the group may not match the present species
count listed in the data summaries. Advise
students to use the data they collected on the
Seamobile when answering their questions.
4. Each student should have returned from the
Seamobile with a “Researcher’s Notebook.”
Near the end of the notebook are three
research questions. Ask students to complete
these, based on the data they’ve collected
and information from the data summaries.
These questions are also found on the
Research Questions worksheet.
5. Once students have answered questions,
ask each group to present their findings,
based on the research questions. By the
end of each presentation, students should
provide a possible reason for the changes
going on in the habitat at their study site.
6. You may refer to the Possible Hypotheses
page to wrap up the investigation. It includes
a list of possible explanations for the changes
observed and recorded by students at each
of the Seamobile study sites. Understanding
the interactions of plants and animals with
their environment is a complex and difficult
process. The hypotheses described for each
site are probably the most reasonable, given the
data available. However, students should
understand that there may be additional
factors which are impacting these sites
and that better predictions would require
additional research.
Extensions
1. Ask students to create a poster presentation
of their findings. Their poster might depict
the interrelationships between the species
in the habitat, as well as their hypothesis
that accounts for the changes in populations
in the habitat.
2. You might consider using this activity with
classes that HAVE NOT participated in the
Seamobile. The data sheets here provide
much of the data necessary for students
to begin to understand how we study
habitats and make hypotheses regarding
what may be impacting those sites.
Natural History Museum of Los Angeles County
Student Worksheet Completing the Seamobile Investigation
2. What kinds of environmental problems might be affecting the plants
and animals living in the habitat you’ve studied? There may be different
problems for different species—try to mention as many as you can.
3. Based on all the data your team has collected, make a hypothesis
(an educated guess) that explains what is causing changes at your
study site. Be specific in your explanation. Use your notes to help you.
Natural History Museum of Los Angeles County
Completing the Seamobile Investigation Student Worksheet
1. Describe any changes that have occurred at your study site over the
past ten years. Think about how the area may have changed and
how the numbers and types of species living there may be different.
45
45
Completing the Seamobile Investigation Data Summary
1
46
Data Summary Station 1
Habitat
Kelp Forest
Study
Species
garibaldi, giant kelp, kelp bass, salema, senorita
Site
Description
This site is located off the coast of Catalina Island, a popular
tourist area surrounded by miles of kelp forests. These undersea
forests provide habitats to over 800 different marine species.
The kelp provides both food and protection to many different
types of marine animals, from the ocean floor to the water’s
surface. Kelp is helpful to humans and is harvested for use in
products such as ice cream, toothpaste, and some medicines.
Transect Count Data
species
señorita
present count
34
previous data
(10 years ago)
Species Impact
53
Senoritas use the kelp forest to hide from
predators. As cleaners, they also rely on
the other fish living in the kelp for food.
Salemas can hide among the kelp blades as
protection from predators. If the kelp forest
was not there, salemas would be easy prey.
salema
44
66
kelp bass
7
22
Since kelp bass prefer to live where there
is some sort of structure (kelp forests, oil
platforms, pilings, etc.), removing that
structure may cause the fish to move to a
different habitat.
garibaldi
22
27
Garibaldi were once threatened by human
over-collection. However, they are now
protected by state law, making it illegal
to catch or spear any garibaldi. Garibaldi
depend on the animals that live within
the kelp forest for their food. Without
the kelp, they would be forced to look
elsewhere for food.
giant kelp
33
65
The giant kelp creates a unique habitat for
many marine species. Destruction of the kelp
forest would force the animals to leave the
area in search of a new habitat, if available.
Scientists are often unable to figure out the
exact causes for the disappearance of a kelp
forest. Perhaps it is caused by severe winter
storms with strong waves that pull kelp up
by its holdfasts. It may be the warm water
temperatures caused by El Niño causing kelp
to wilt and die. Sewage and pollution can also
destroy a kelp forest by covering rocks with
slime or sludge, which preventing new kelp
from attaching.
Natural History Museum of Los Angeles County
Habitat
Study
Species
Site
Description
Continental
Slope
basket star, fish-eating star, lingcod,
rockfish, white anemone
This site, near Catalina Island, is a deep water habitat. The
mixing currents at this location create nutrient-rich water
full of food for the marine life. Lots of food means lots of
fish in the area, too. The large number of fish brings many
fishermen (and boats) to the area during the fishing season.
Commercial fishing and tourism also occur in this area.
Transect Count Data
species
present count
previous data
(10 years ago)
Species Impact
Rockfish are a favorite sports fish. Rockfish
do not migrate and many spend their adult
life in one area, making easy targets for
the fishermen.
rockfish
7
55
basket star
10
15
lingcod
1
12
Lingcod are prized for food and are also
very popular with fishermen. Off Southern
California, commercial fishermen will also
catch large numbers of these fish in gill
and trawl nets.
white
anemone
17
25
White anemones are not commonly
collected by people for any reason. They
reproduce quickly, so the few that are
collected are rapidly replaced. However,
the weights of trawl nets can damage
or kill anemones as the nets are dragged
across the bottom to catch fish.
fish-eating
star
6
8
Natural History Museum of Los Angeles County
Basket stars are rarely caught by fisherman
for food. Deep water trawl nets used to
catch bottom fish can accidentally catch,
move, injure or even kill basket stars as the
net drags along the bottom.
The fish-eating star is not collected
commercially for any reason, but collection
methods for other animals, such as trawl
nets that drag along the bottom, may
disturb their habitat. Because the deep
sea is difficult to study and this sea star
is uncommon, it is difficult to accurately
determine what factors might threaten
this animal’s survival.
Completing the Seamobile Investigation Data Summary
2
Data Summary Station 2
47
3
Completing the Seamobile Investigation Data Summary
48
Data Summary Station 3
Rocky
Bottom
Habitat
Study
Species
moray eel, opaleye, red sea urchin,
southern sea palm, warty sea cucumber
Site
Description
This site is located off the coast of Palos Verdes, near the
largest sewage treatment plant in Los Angeles County. Before
pollution control was improved, this plant collected and discharged
pesticides and other chemicals from local industries into the ocean.
Oil, debris and other waste are still washed into the ocean from
streets and parking lots during storms. Runoff during heavy
rains can also cause the treatment plant to overflow, forcing
incompletely treated sewage into the ocean.
Transect Count Data
Species
present count
previous data
(10 years ago)
red sea
urchin
2
7
warty sea
cucumber
3
4
opaleye
14
25
moray eel
1
1
southern
sea palm
8
23
Species Impact
If the food source of the red sea urchin is
not readily available in an area, the urchin
population may be in danger since they are
not as mobile as other marine animals and
can not easily relocate to another habitat.
Some bottom feeders like the warty sea
cucumber have become tolerant of pollutants
in the ocean sediments where they eat and
live. However, if poisons collect in the tissues
of the cucumber, there may be problems for
animals that try to eat it.
Opaleye feed primarily on kelp, but will
also eat some small invertebrates. Toxins
may accumulate in these fish if they eat
contaminated invertebrates. Also, polluted
areas that cannot support a healthy kelp
bed severely affect the number of opaleye.
Moray eels reproduce in the warmer waters
of Baja, Mexico and become permanent
residents of the southern California waters
once they mature. Once they are settled into
their new habitat and become part of the
local food web, they may be accumulating
toxins in their bodies from the food they eat.
Like plants on land, the southern sea palm
provides both food and shelter to marine
animals. Some coastal runoff, like oil and
pesticides, may be poisonous to the sea
palms. In other cases, materials from
sewage discharges and stormwater runoff
may cause local waters to become more
cloudy, blocking the amount of sunlight
that gets to the sea palms. Without
enough light, these plants cannot survive.
Natural History Museum of Los Angeles County
Habitat
Study
Species
Site
Description
Sandy
Bottom
California spiny lobster, halibut, horn shark,
Kellet’s whelk, blackbelly eelpout
This site is located at the entrance to the Los Angeles/Long
Beach Harbor. The harbor is one of the world’s largest with
very heavy traffic. Shipping lanes are designated in and out of
the harbor, much like driving lanes, to control the flow of the
ships. To make sure that the ships can enter the harbor, the
ocean bottom is frequently dredged, or dug up, to make a clear
passage. Dredging severely disturbs the harbor’s sandy bottom.
Transect Count Data
Species
present count
previous data
(10 years ago)
horn shark
3
5
halibut
1
12
blackbelly
eelpout
1
6
California
spiny lobster
1
12
Kellet’s
whelk
10
7
Natural History Museum of Los Angeles County
Species Impact
Horn sharks are “bottom dwellers.” Disturbing
the ocean floor may impact or destroy the
other animals like clams and snails that the
horn shark comes to feed on. This may force
the shark to look elsewhere for its meals.
Halibut are also bottom dwellers, spending
most of their time on the sandy bottom in
relatively shallow waters off the California
coast. Changes to the ocean bottom, such
as dredging, can cause problems for halibut
by destroying their habitat or displacing the
animals that the halibut feeds on.
Blackbelly eelpouts often protect themselves by
burying into the ocean bottom to hide from
predators. However, trawl nets that drag the
ocean bottom commonly catch eelpouts. Other
changes to the ocean floor, such as dredging or
dumping, may disturb or even bury these fish.
California spiny lobsters often search the
sandy bottom areas for food at night. Algae
and most of the other food sources for the
lobster live on the ocean bottom and are
sensitive to changes that might disturb the
area. If no food source is available, the
lobsters will move to other areas to hunt.
Often found on shallow bottom areas, Kellet’s
whelks are scavengers. Fishing vessels in
coastal areas often dump their waste fish
parts and accidental kills back into the ocean
before docking in the harbor. This trail of
decaying and injured animals on the ocean
floor can be very attractive to the whelks.
With few predators and plenty of food,
their population can grow very quickly.
Completing the Seamobile Investigation Data Summary
4
Data Summary Station 4
49
5
Completing the Seamobile Investigation Data Summary
50
Data Summary Station 5
Continental
shelf
Habitat
Study
Species
box crab, spiny brittle star, sunflower star,
giant Pacific octopus, hagfish
This deep water site is located off the coast of Orange
County near Corona Del Mar. About five years ago, a ship
spilled its cargo of copper powder near this site. Copper is
a heavy metal and is known to be particularly toxic to many
marine organisms. The powder eventually settled to the
bottom, and has become part of the ocean floor sediment.
Site
Description
Transect Count Data
Species
present count
previous data
(10 years ago)
hagfish
1
2
box crab
18
36
sunflower
star
4
6
spiny brittle
star
giant Pacific
octopus
16
1
40
6
Species Impact
Little is known regarding natural threats
to hagfish.
Like many bottom dwellers, box crabs are
sensitive to pollution from runoff or
accidental spills which accumulates on the
ocean floor. Some heavy metals, like
copper, may actually interfere with the
crab’s ability to use oxygen.
Sunflower stars are not particularly
sensitive to pollution themselves and are
not impacted by human harvesting. As
long as their food source of brittle stars,
sea urchins and other invertebrates is
available, sunflower stars will survive.
Scientists have discovered that the number
of some species of brittle stars drops
significantly in polluted waters. As you
move further and further away from the
polluted area, these brittle star populations
begin to increase. The exact reason of
how the pollution affects the brittle stars
is not clear—scientists are still studying
this problem.
The giant Pacific octopus is collected commercially as a source of food for humans.
Their survival also depends on the health
of their ocean habitat. Chemical pollution,
from dumping or accidental spills, often
settles to the sea floor, where it accumulates
in the bodies of the marine animals, like
clams and lobsters (and even octopus).
These poisonous chemicals may kill these
animals, or simply make them poisonous
to other animals that eat them.
Natural History Museum of Los Angeles County
Site 1
Kelp Forest
HABITAT DESTRUCTION
These undersea forests located near Catalina
Island provide habitats to over 800 different
marine species. Destruction of the kelp, whether
caused by man or nature, forces these animals
to relocate and find shelter and food in other
areas. (Students need not speculate the cause
of the kelp loss—rather just understand its
impact on the habitat.)
part of the ocean sediment. The site is also
located near a County water pollution control
plant wastewater from over 4 million people
a day is treated and released into the ocean.
These forms of pollution may be responsible
for poisoning local species or killing their sources
of food or shelter (e.g. southern sea palm)
through water or sediment contamination.
Site 4
Sandy Bottom
HARBOR OPERATIONS
Site 2
Continental Slope
OVERFISHING
This location, on the west end of Catalina
Island, is an area of mixing currents and deep
water upwelling, creating and maintaining
nutrient rich water. The high level of nutrients
means there is much food in the area for fish.
In this case, lots of fish means lots of fishing.
During the fishing season, large numbers of
boats and sportsfishermen can be found in this
area. Commercial fishing also takes place in the
area, involving large gill nets (nets that catch
fish by entangling their gills) and trawl nets
(nets towed behind boats, often moving on
or near the bottom of the channel). Excessive
fishing may significantly alter this community.
Site 3
Rocky Bottom
COASTAL RUNOFF
The site is located off the coast of Palos Verdes,
an area known for old deposits of pesticides
like DDT and significant surface runoff. Years
ago, pesticide manufacturers dumped chemical
waste into the ocean and it has now become
This site is located at the entrance to the Los
Angeles Harbor. This area is subject to dredging
operations which maintain clear passage for
ships entering and leaving the harbor. Dredging
severely disturbs the sandy bottom environment.
Also, an unusually high number of dead and
decaying fish litter the ocean bottom, possibly
due to these dredging operations or the actions
of commercial fishermen dumping their fish
waste parts or unwanted catch before entering
the harbor. This may be contributing to an
increase in the number of scavenging species
(like the Kellet’s whelk).
Site 5
Continental Shelf
COPPER SPILL
This deep water site is located off the coast near
an area where a ship spilled its cargo of copper
power nearly five years ago. Copper is known
to be particularly toxic to many marine organisms
and since the powder eventually settled on
the ocean floor, bottom dwellers would have
been extremely susceptible to this pollution.
Organisms not directly affected by the copper
might be affected by the loss of a food source
which was poisoned by the heavy metal.
Natural History Museum of Los Angeles County
51
Possible Hypotheses for Habitat Changes
Below is a list of possible explanations for the changes observed and
recorded by students at each of the Seamobile study sites. Understanding
the interactions of plants and animals with their environment is a complex
and difficult process. The hypotheses described below for each site are
probably the most reasonable, given the data available. However, students
should understand that there may be additional factors which are impacting
these sites and that better predictions would require additional research.
Completing the Seamobile Investigation Possible Hypotheses
Possible Hypotheses
Making Sense of It All
Career Focus: Oceanography
52
Career Focus: Oceanography
Oceanography (or Marine Science) is the scientific study of the physical
and biological components of the Earth’s oceans. This field of study draws
on several disciplines, integrating biology, geology, physics, chemistry,
and engineering as they relate to understanding the ocean.
Marine biology, one of the main branches of oceanography, involves the study of ocean
plants and animals and the interrelationships between them and their environment. Marine
biologists may also focus on the effects of pollution and human intervention on the organisms
living in the ocean.
Marine Geologists map the ocean floor, study shoreline problems, examine plate
tectonics and seafloor spreading, and analyze characteristics of seafloor sediments.
Physical Oceanographers study wave dynamics, tides and currents, ocean/atmosphere
interactions, water density, temperature, and underwater acoustics and sound transmission.
Chemical Oceanographers are concerned with the chemistry of seawater, its major salts,
and its many trace elements. These scientists also study the ocean’s dissolved solids and gasses
and the relationships of these conditions to the geology and biology of the ocean as a whole.
Marine Engineers design and build oil platforms, ships, harbors, and other structures.
Students interested in an oceanography career typically enroll in a variety of
science and math classes in college, including biology, chemistry, physics
and geology. Although all marine scientists specialize in one area of
research, they must also be familiar with other marine science disciplines
to appreciate and make connections between them. Marine science
contributes to our awareness and appreciation of the interconnection of
all natural environments.
Natural History Museum of Los Angeles County
How do we affect the health of our land and oceans?
Background
The Seamobile provides students a glimpse into a complex ecosystem located a short distance
from their school yard. One of the goals of the Seamobile experience is to help promote care
and concern for the ocean environments by introducing students to the plants and animals that
live there. By bringing children an awareness of the wildlife and relationships in nature, and
reinforcing the skills to make thoughtful decisions, we can help them understand their roles
and responsibilities in the world around them.
What environmental problems do we face in California?
Water Pollution. Coastal pollution takes many forms: sewage overflows, chemical dumping,
and solid waste are just a few. These problems do affect our recreational use of the seashore,
but more importantly, they impact the entire marine ecosystem. Dolphins, seals and marine birds
become entangled in plastic netting or six-pack rings. Other marine animals mistake plastic bags
for food, leading to plastic-filled stomachs and starvation. It seems that our naive use of the sea
as a dumping ground has jeopardized the lives of thousands of unique creatures.
Coastal Runoff. The oil that is in the ocean is caused primarily by runoff from the land,
rather than large tanker accidents. Each year, 240 million gallons of used motor oil is dumped
down drains, poured into dirt, or concealed in trash that goes into landfills. There is also an
increase of paint, cleaning fluids and pesticides that are being inadvertently washed into storm
drains, which run into the ocean. Oil in the water clogs feathers and fur. It keeps plants from
photosynthesizing, due to the dark layer it leaves on the surface of the water. The pesticide
DDT settles to the bottom of the ocean and can affect the ocean floor environment for years.
Caring for an Ocean Planet
Caring for an Ocean Planet
Overharvesting. The oceans of the world provide an important source of food to many
people. Unfortunately, we are exceeding the maximum amount of fishes we can safely take
from the oceans. This means a decrease in the numbers of fish available and a decrease in the
average size of fishes left. Shrimps and orange roughy are just two of many marine species
being threatened by our ever increasing appetite for seafood. Many of the species that are
overharvested cannot recover from such severe depletion. Fish are unable to reproduce before
they are cought and young may be taken before they are mature, In addition, the fishing
methods used for many marine animals may severely disturb their ocean habitats, or result
in the inadvertent collection of other marine species.
Changes in Land Use. Who has the right to use the land? The use of private and public
lands are being debated as people scramble for more open space. Loss of wilderness areas on
land and at sea, means a change in the local ecosystem and a loss of biological diversity. In many
cases we are forced to choose between the welfare and livelihood of those who would benefit
from the new land use and loss of an entire animal species.
Natural History Museum of Los Angeles County
53
Caring for an Ocean Planet
What can we do?
Although these environmental issues seem to broadcast imminent doom,
it is important that students realize that each of them can make a
difference in important ways. If everyone does a just a small part and
learns how to better care for their environment and natural resources,
the effects can be large. Here are some simple things that we can do.
Conserve Energy. Using more electricity typically means burning more fossil fuels, which
means depleting nonrenewable resources, possibly increasing demand for additional offshore
oil drilling and contributing to air pollution. Help cut down on energy consumption. Put on a
sweater instead of turning up the thermostat. Walk to the grocery store only two blocks away
instead of driving. Turn off lights and appliances when you leave the room. It’s that simple!
Put Trash in its Place. What happens to trash that doesn’t make it into the garbage
can? It doesn’t just disappear, although it may seem like it does. Much of the litter we drop,
as well as the oil and grease on our roads, ends up in our sewers or drainage channels, where
it makes its way to the ocean. A plastic potato chip bag dropped in the San Fernando Valley
can end up in the stomach of a dolphin off the coast of Malibu. Even our actions on land 30
miles from the coast can adversely impact habitats at sea!
Conserve Water. Fresh water is something we often take for granted, but most of our fresh
water in Southern California is imported. (Much of the local groundwater has been contaminated
by industry over the past sixty years.) Aqueducts bring water from Northern and Central California,
as well as the Colorado River. Los Angelenos’ high demand for water is having a negative affect
on natural habitats in these areas and may impact the future of these water sources. Taking
baths instead of showers, installing “low-flow” toilets, and washing full loads of laundry can all
help reduce water consumption. Also remember that Los Angeles is a naturally dry area, consisting
of chaparral and desert habitats. A luxurious green and constantly-watered lawn could be replaced
with drought-resistant plants and landscaping. Otherwise, grass-covered lawns can be watered
during evening hours when evaporation is slowest, allowing more water to soak in.
What happens to the future of the Earth, and all the living things on
it, depends on what we do today. It is our responsibility to see (and
help others see) how our actions, large and small, bad and good, can
impact our world. As John Muir said, “When we tug on one thing in
the universe, we find it attached to everything else.”
54
Natural History Museum of Los Angeles County
Gone Fishing
Students will model old and new fishing technology and examine
the effects that the different methods have on fish populations
and biodiversity.
In this activity, students will go “fishing” with different levels of technology and see what
effect it has on the fish population in the ecosystem.
Procedure
1. Divide the students into teams of two and
distribute materials to each team. The teacher
will place about 15 candies (representing fish)
in each bowl. Students should record the
total number of “fish” in the “Old Method”
section of the data table. Remind them
that they shouldn’t eat their fish (although
they may get to at the end of the activity.)
2. One person in each team will represent the
ocean ecosystem and hold the bowl. The
other student will represent the fisherman
(or woman) that will fish from the ocean
and will have the tweezers (or chopsticks)
and the empty cup.
3. Students (fishers) have 30 seconds to move
as many fish as they can from the ocean
into the collection cup using the tweezers.
Students should record the number of fish
caught and the number of fish still remaining
in the ocean using the data sheet provided.
4. Replace one half the number of fish that
are remaining in each team’s ocean
ecosystem. For example: if there are 10
fish left in the bowl, the teacher would
add 5 additional fish, as the fish would
have had some time to mate and produce
offspring. Students should record the new
total of fish, including the new additions.
6. Inform the fishermen that there have been
some developments in fishing technology.
The spoon method has been invented; the
tweezers (or chopsticks) method is outdated.
The fishermen will now have 30 seconds
to take as many fish as possible using the
spoon. Remind students to record their
beginning population before fishing in the
section marked “New Method”. When
time is called, students should complete
the data table as before.
7. As before, replace one half the number of
fish that are remaining in each team’s ocean.
If there are no fish remaining in the bowl,
the students do not get any additional fish
because they have depleted all of the
population and there are no fish left to breed.
8. Continue the exercise once more with the
spoon, record data, then have students
answer the questions on their data sheet.
Materials
small paper bowl
(one per team)
tweezers or chopsticks
(one per team)
plastic spoon
(one per team)
paper cup
(one per team)
large bag of M&Ms™
or similar candies
Gone Fishing Worksheets
Activity time
20-30 minutes
Process skills
Communicating
Comparing
Relating
Teaching Tip: If you tell
Extension
5. Ask students to go fishing one more time.
Students should again record the number of
fish caught and number of fish remaining.
Allow the fish to reproduce by adding more
candies as before. Students should record
their final fish population on the data sheet.
Natural History Museum of Los Angeles County
Proceed with the experiment the same way,
but tell the fishers that the only fish that they
want to catch are the brown ones. However,
once a fish of any color is caught, it must be
removed and can’t be thrown back. When the
students have completed this variation, ask
them to consider the following questions.
your students ahead of time
what will happen to their
populations when no fish are
left, chances are this activity
may cost you a lot of M&M’s™.
Let the teams weigh the
consequences themselves.
Caring for an Ocean Planet
Not long ago, fishing in the ocean was a slow and tedious task, with relatively few fish being
brought in with every voyage. Today, technology has made it possible for fishing vessels to take
in thousands of fish in a relatively short amount of time. While this benefits the fishing industry
in the short term, it may cause fish populations to quickly decrease to the point where they can
not recover. If one species is removed from the ecosystem, the imbalance is felt up and down
the food chain, with other populations either growing out of control because nothing is eating
them, or dying because they have nothing to eat. Entire ecosystems can begin to die out when
there is less variety of life, or biodiversity, in the area.
Gone Fishing pre-visit, post visit
Introduction
How easy is it to just pick out just one type of fish?
Does it matter which method you use?
What if you couldn’t see the fish at all?
Would you be more likely to pull up a fish
or another animal that you couldn’t use?
What do you think happens to those unwanted fish?
How might this affect the biodiversity of the area?
55
Student Worksheet Gone Fishing
Complete the data tables below. Be sure to count and record the
total “fish” population before each catch.
Gone Fishing Student Worksheet-Data
Old Method
1st catch
2nd catch
Beginning
Fish Population
number of
fish caught
number of
fish remaining
number of
new fish
Final Fish
Population
New Method
1st catch
2nd catch
Beginning
Fish Population
number of
fish caught
number of
fish remaining
number of
new fish
Final Fish
Population
56
Natural History Museum of Los Angeles County
Student Worksheet Gone Fishing
2. Why didn’t the fish population go back to the original number after every turn?
3. What problems do you think this new method of fishing might cause the food chain in the area?
4. How would the new technology affect the ecosystem as a whole?
5. What do you think happened to the commercial fishermen’s
profits immediately after they started using the new technology?
Gone Fishing Student Worksheet-Questions
1. What happened as the fishing technology improved?
6. What do you think will happen to the commercial fishermen’s profits in the following years?
Explain.
7. How do you think this problem could have been prevented?
8. What might a regular consumer do to help with the problem of overfishing?
Natural History Museum of Los Angeles County
57
About Fishing
Quick Info:
In the past sixty years, the fishing industry has
changed dramatically. New technologies that
enable fishermen to significantly increase their
catch have been introduced to the fishing community. With these new methods and new nets,
fishermen are taking millions more fish per year from
the oceans. Listed below are some of the fishing methods that
are being used in the oceans today.
Trawl Nets Funnel shaped
nets that are dragged behind
boats. These nets act as a
scoop for any fish, shrimp or
other marine animal. Dead,
unwanted fish are thrown
back into the water after the
net is brought up to the boat.
About Fishing
Gill Nets Vertical walls of netting
designed to let fish of a certain size
swim part way through, only to get
stuck in the netting by their gills.
Thousands of unwanted fish get
caught and die in gill nets every day.
Purse-Seine Nets Nets that encircle entire schools of
Angling/Sports Fishing
Fish are caught one at a time using
poles and bait or lures. If large
groups of anglers fish in a small area
over a long period of time, the
fish populations can significantly
decline. In most cases, however,
sports fishing has a much smaller
impact on an ecosystem than
large scale commercial fishing.
fish, then close at the bottom like a pouch to prevent
fish from escaping. Hundreds of thousands of fish are
caught at one time. Dolphins are often caught in this
type of net and drown when they are unable to come
up for air. In the 1990’s, consumers became aware of
this method of fishing and boycotted tuna that was
caught in this way. Most United States tuna companies
stopped using purse-seine nets because of this, and
the boycott ended successfully.
Consumers that are well informed are the best defense against the
problem of overfishing. If consumers chose to eat only fish that were
caught by responsible fishing methods, the fishing industry could be
forced to change their practices. Eating only hatchery-raised fish is
another thing that consumers can do to ensure that the ocean fish
populations remain stable.
58
Natural History Museum of Los Angeles County
Too Much of a Good Thing?
Students will learn the impact of overenriching the marine environment
with nutrients that are by-products of human activity.
When too many nutrients are introduced to the marine environment, single-celled plants, called
phytoplankton, bloom or become too abundant. The presence of the increased number of
phytoplankton causes the water to change color and blocks the sunlight from the deeper beds of
plant life that provide food and shelter for many marine animals. These plants can die when light
is reduced. Also when the large quantities of phytoplankton die and sink to the bottom, the
process of decay consumes oxygen from the water. This affects other marine life.
Procedure
1. Fill each jar with 750 ml of water.
2. Add 10 mg of fertilizer to the first jar and 25 mg of fertilizer to the second jar.
3. Add 10 mg of fertilizer to the third jar and cover it completely with aluminum foil.
This is the control sample for light. It will be used later for comparison.
4. Don’t add anything to the water in the fourth beaker. This is the control for fertilizer.
This sample will also be useful for comparison.
5. Label and date the jars and place them near a good light source, either in a sunny window
or in strong artificial light. Do not put them in a cold place.
6. Students should record observations of the jars every day or two and note any changes
they see. The algae should begin to grow in the jars with fertilizer in about ten days while
the non-fertilized jar (#4) should stay fairly clear.
7. There are two variables being manipulated in this experiment: amount of fertilizer and amount
of light. As the experiment progresses, ask students to answer the following questions.
How does the amount of fertilizer affect algae growth?
What evidence supports your conclusion?
How does the amount of light affect algae growth?
What evidence supports this conclusion?
Based on your observations, why might too much algae growth be harmful?
Extensions
1. After completing the above experiment, ask students to test the acidity of the water in the
jars using litmus or other paper indicator. Then add 1/4 to 1/2 cup of vinegar to each and
test acidity again. The vinegar here simulates acid rain or acidic runoff. Allow students to
observe and record their findings for several days. The water should become very clear as
the acid kills all the algae in the water. Challenge students to think about how they might
reduce the acidity of the water and whether or not the algae would be able to grow again.
2. Obtain some Elodea from a tropical fish store and add to the first two beakers. (Elodea is
a type of fresh water underwater plant.) Ask students to predict what will happen to the
plant after a few days or weeks and then observe and record its growth. The Elodea will
be competing with the algae for resources. Initially it should do well, but eventually it will
die because of the increased algae growth.
Natural History Museum of Los Angeles County
Materials
four equal size clear jars or bottles
of one liter or more
water with algae from a freshwater
pond, stream or aquarium
commercial plant fertilizer
good light source
Activity time
2-3 weeks
Process skills
Observing
Communicating
Relating
Inferring
Caring for an Ocean Planet
Nutrients such as nitrogen and phosphorus are essential for life, but too many nutrients can
cause the marine environment to get out of balance. Nitrogen and phosphorus occur naturally
in the water, soil and air, but are also found in human sewage, animal manure and plant fertilizer.
Sewage treatment plants dump partially treated human waste into the ocean, and water running
off from the surface of the land carries fertilizers and other pollutants to the streams and rivers
that feed into the ocean.
Too Much of a Good Thing? post-visit
Introduction
59
Caring for an Ocean Planet
What a Mess!
Students devise methods for “cleaning up” a simulated oil spill and
compare their procedures to actual procedures used for real spills.
Introduction
Materials
What a Mess! post-visit
for each student team:
a foil pan or plastic container,
approximately 9"x9"x2",
filled with water
2 straws
piece of yarn (18")
paper towels
small spray bottle filled with
water and dish soap
2 paper cups
eye dropper or disposable pipet
cooking oil
(4 tablespoons per team, plus refills)
Activity time
45-90 minutes
Process skills
Observing
Communicating
Comparing
Relating
Inferring
Connections
Physical Science
Engineering
60
Although water and oil don’t mix, oil spills are quite difficult to clean up. There are several different
methods used today, each appropriate for different situations. Containment booms are placed
around oil floating on the surface of the water to keep the oil from spreading. Chemical dispersants
are used to break up floating oil and make it sink to the bottom of the ocean. Skimming is essentially
vacuuming the oil from the surface of the water. Oil absorbent towels and other materials are
used to remove oil, especially on contaminated shorelines. Finally, bioremediation is sometimes
used, where microorganisms that feed on the oil are introduced to the spill in order to “eat it away.”
Part A. Testing Procedure
1. Set up the “oil spills” prior to class time by adding about 1.5” to 2” of water
to each team’s pan, followed by about 4 tablespoons of cooking oil.
2. Introduce the challenge:
“What is the best way to remove the oil from the water?”
Then state the ground rules:
A) Water cannot be dumped or siphoned out of the container.
B) Only the materials provided can be used.
C) Each attempt must be recorded on a data sheet.
(Don’t introduce the idea of oil spills yet— simply let the students attempt to complete the task.)
3. Distribute a copy of the data sheet provided to each student. For each method they attempt,
the team must describe what materials were used and how they cleaned the oil. Encourage
students to stick with one procedure until they have cleaned their water, or at least until they
have a feel for how effective their method is.
4. Once they have derived one procedure, ask the team to go back and try again, this time with
different tools. You may need to add more oil to their water supply, or in some cases, completely
refill their container. Each team should come up with 2 or 3 ways to clean their water.
5. Once students have completed their investigations, ask students to rank their methods for
cleaning in two separate categories: most effective (the test that removed the most oil while
leaving the water behind) and easiest (the test that required the least amount of time and effort).
Natural History Museum of Los Angeles County
What a Mess!
Part B. Comparing Data
1. Ask each team to make a list of difficulties they had in cleaning their water, considering
any of the methods they used. Ask each team to share their findings and create a class
list. Try to help clarify each group’s reasons and promote questioning, without necessarily
designating right or wrong answers.
2. Inform students that many of the methods they used in cleaning the water are similar
to methods used to clean oil spills in the ocean. Ask the teams about their results. Guide
discussion using questions like the following:
What is the difference between the ‘best’ way and the ‘easiest’ way to clean the oil?
Using your ‘easiest’ method, did you take just oil out, or oil with a lot of water?
What about your ‘best’ method?
Which method would be most expensive?
When cleaning up an actual oil spill, how do you think people decide which method(s) to use?
3. Distribute the handout “Disaster in the North Pacific!” Ask each team to read the scenario
and consider which method might be “best” for this situation. Ask each team to draft a
one page clean-up proposal for the oil spill, stating which method or combination of
methods they would recommend. Each team MUST support their proposed strategy using
data from their testing and any other information discussed during class.
The scenario in “Disaster in the North Pacific” is fictional, but is based on information
from several real situations.
4. Read to the students the information from “Disaster Follow-Up”, including the methods
used and the actual results of those actions. Following this, debrief the class, touching on
the following points:
In order to make informed decisions, scientists often use models
to better understand a situation.
The more variables there are in any given situation,
the more difficult it is to predict outcomes.
There is no foolproof way to completely clean up an oil spill.
It is a very difficult and unpredictable process.
Natural History Museum of Los Angeles County
Teaching Tip: Consider
reviewing or introducing the
concept of density as a way of
helping students understand
why oil floats. See “That
Sinking Feeling” for suggestions. You might also review
the idea of solubility to remind
students that oil can’t really
mix with water. The phrase
“like dissolves like” can be
used to indicate how similar
liquids can mix (like water and
food coloring), but dissimilar
liquids (like oil and vinegar)
cannot. Some chemicals, like
dish soap, can surround oily
liquids and make them more
soluble in water.
61
Student Worksheet What A Mess!
What we used (materials)
What we did (procedure)
Test 1
What A Mess! Student Worksheet
Test 2
Test 3
Which test was the easiest way to remove the oil? Explain.
Which test removed the oil the best or was most effective? Explain.
62
Natural History Museum of Los Angeles County
The Los Angele
s Tides
Disaster in the
North Pacific!
October 25, 1991
SITKA, AL ASK
A - A large
American oil ta
nker has collided with a fi
shing boat
approximately
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just north of th
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side of the
tanker has
allowed nearly
100,000 barrels (4,200,000
gallons) of
crude oil to esca
pe into the
Pacific Ocean
. The local
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Natural History Museum of Los Angeles County
What A Mess ! Los Angeles Tides
25 cents
63
Student Information Sheet
What a Mess!
What a Mess! Student Information Sheet
Disaster Follow-up
64
Disaster Follow-up
Cleaning It Up
The oil was first corralled into containment
booms (the quickest method of containing large
amounts of oil) which surrounded the largest
oil slicks at the water surface. The oil was then
removed from the top of the contained water
with skimmers that were pulled behind boats
equipped with vacuum-like tubes to suck the
oily water up. These quick and easy methods
only worked for the largest slicks, however.
soaked with oil and became inedible. Over one
hundred bald eagles, who nest in the area, were
reported to have died the year after the spill.
Marine fisheries such as the salmon industry
have been hard hit by below-average catches
since the spill, though research shows that this
is due to both the oil spill and the overfishing
of the entire area.
The Oil Company has agreed to pay for most
of the clean up and research.
Ten Years Later
Ten years after the oil tanker accident in the
waters near the town of Sitka, Alaska, scientists
have completed a report of the long-term
impacts of the spill. They say that in many ways
the ecosystem has proven surprisingly strong,
with some plants and animals recovering nicely.
The marine mammal populations are finally
growing after eight years in decline, and some
of the seabirds are breeding normally again.
Most species, however, still have a long way
to go for recovery, including the bald eagles,
The clean-up crews also tried adding a chemical which are still having oil-related problems with
dispersant to make the oil mix with the water their eggshells being too thin for their chicks
and then sink. Environmental groups protested to develop properly. There is also some oil that
this, saying that letting the oil sit on the ocean has been trapped underground that, even now,
floor was just as bad for the ecosystem as letting occasionally leaches to the surface to create
it stay on the surface. People also feared that new hazards.
the chemicals were as harmful to the ocean
environment as the oil itself.
In all, the plant and animal populations seem
to have adjusted themselves in response to the
Even after using all of these methods, thousands spill. The scientific studies done on this spill, and
of gallons of oil still made it to the shore. Over effectiveness the clean-up methods that were
200 miles of shoreline were affected. Thousands used, have proved helpful by limiting damage in
of animals died as oil got into their fur or feathers, more recent spills. Scientists and environmentalists
preventing them from keeping warm in the cold agree that a faster response time and more
waters. Still more animals died when their food effective removal methods are important goals
sources, such as shellfish or marine plants, were for managing future oil spill incidents.
Workers went after the smaller patches of oil
with sorbents, or special sponge-like towels
that soaked the oil off of the water surface.
This method was very time consuming, with
thousands of people working long days. One
crew started burning the oil from the surface
of the water in a small area, but smoke from
the fires proved toxic and dangerous to other
workers and the people living in nearby houses.
Natural History Museum of Los Angeles County
Measurements and
Conversions Appendix A
Length
While inches and feet are the measurements of length (or depth) commonly used in the
United States, other countries and most scientists use units of centimeters and meters.
One meter equals 3.281 feet. To translate meters into feet, multiply the number of meters by 3.281.
Example: For 100 meters
F = 100 x 3.281
F = 328.1 ft
Other Useful
Length Conversions:
To translate feet to meters, simply divide by 3.281.
Example: For 1000 feet
1in =
1 mile =
1 mile =
1km =
1m =
M = 1000 / 3.281
M = 304.8 m
Temperature
There are several different scales used for measuring temperature. In the United States, Fahrenheit
degrees are used in everyday life. In most other countries, Celsius degrees are used. The Celsius
scale is commonly used by scientists around the world, including scientists in the United States.
The boiling point and freezing point of water are often used as reference
points when measuring temperature.
On the Fahrenheit scale:
32˚F is the freezing point of water;
212˚F is the boiling point of water.
To convert Celsius into Fahrenheit:
multiply the number of degrees
Celsius by 9⁄5 or 1.8 and then add 32.
On the Celsius scale:
0˚C is the freezing point of water;
100˚C is the boiling point of water.
Example: For 100˚C
F = (100 x 1.8) + 32
F = 180 + 32
F = 212˚F
2.54 cm
5280 ft
1.61 km
1000 m
100 cm
Appendix A Measurements and Conversions
An important part of collecting data is making measurements. Throughout the Seamobile
program, students will be measuring different quantities, including depth, temperature and
pressure. A description of these measurements and common conversions is included below.
Pressure
The particles of air around us are constantly bumping into things. The force of these “bumps”
is called pressure. At sea level, the pressure caused by air is about 14.7 pounds per square inch
(psi). That is, there is almost 15 pounds pushing on every square inch of area. Another unit used
to measure pressure is the atmosphere (atm). One atmosphere is equal to 14.7 psi.
To convert atmospheres to pounds per square inch, simply multiply atmospheres by 14.7.
Example: For 5 atm P = 5 x 14.7
P = 73.5 psi
As you go deeper in the ocean, pressure increases in the amount of one atmosphere ( or 14.7 psi)
for every 10 meters (32.8 feet) you descend. To find the pressure in pounds per square inch (psi),
divide the depth in meters by 10, multiply by 14.7 and then add 14.7 to the total. (The additional
14.7 psi accounts for atmospheric pressure.)
Example: For 50 meters
P
P
P
P
=
=
=
=
(50/10 x 14.7) + 14.7
(5 x 14.7) + 14.7
73.5 + 14.7
88.2 psi
Natural History Museum of Los Angeles County
65
Randy Harwood
Glossary
Appendix
B Glossary
Glossary Appendix B
algae Plant-like organisms that live mostly in water. Can exist as exoskeleton Hard outer covering of some invertebrates.
single-celled free swimmers or as multicellular seaweed.
gas bladder Small gas-filled floats that help a plant or animal
aphotic zone Area of the ocean to which sunlight never reaches; float in the water. Gas bladders hold kelp blades toward the surface
also called the dark zone.
where they receive sunlight. They also help fish swim upright.
Arthropods Invertebrates that have a hard exoskeleton and
invertebrate Animal that does not have a backbone.
Mammals Warm-blooded vertebrates that have hair and
jointed legs.
bioluminescence Production of light by a living organism.
camouflage Ability to blend into the surroundings by means of
body coloration, patterns, and shape.
carapace Part of an exoskeleton that covers the head and thorax
(chest) of some arthropods. Also, a sea turtle shell.
cartilage Tough, elastic connective and supportive tissue found
in many animals. Some fish, like sharks, have an entire skeleton
made of cartilage.
cartilaginous Made of cartilage.
Cephalopods Class of marine mollusks; including octopuses,
squids, and nautiluses.
chromatophores Skin cells containing pigment. Allows some
animals, like squid, to change color.
Cnidarians Soft invertebrates with tentacles that have
stinging cells.
produce milk.
Mollusks Invertebrates with soft bodies. Often protected by shells.
marine snow Another name for detritus; used to describe
matter drifting down from the surface.
natural history Detailed description of a species and its lifestyle.
operculum Cover for the opening of the shells of gastropods
(like snails) and, a plate covering the gills of bony fish.
overfishing Taking too many fish and seriously depleting its
numbers, potentially affecting the future existence of that species.
overharvesting Taking too many plants or animals for human
use, depleting the numbers and impacting the future of the species.
photic zone Area of the ocean through which sunlight penetrates.
photosynthesis Process which occurs in green plants where
light energy is used to create food.
phytoplankton Microscopic plants that float near the
compound eyes Single eye structure containing several
light-sensing units.
ocean’s surface.
continental shelf Gradually sloping area of land that begins
and sea lions.
at the shore and continues under the ocean.
continental slope Steeply sloping area of land located beneath
the ocean.
Crustaceans Mostly aquatic class of animals that includes
shrimp, lobsters, crabs, barnacles and others.
colonial animal Animal in which many small individuals grow
together, making one large body.
detritus Small bits of matter, such as decaying plant and animal
parts, and animal waste. Provides food for some animals living
in the deep, lightless regions of the sea.
dichotomous Dividing or branching into two parts; in a
dichotomous key, two questions are asked about an item in
order to help classify it.
dorsal refers to the back of an organism, such as the dorsal fin
of a fish
Pinniped Group of marine mammals that contains seals
preopercle Cover over the smaller gill opening of bony fish.
radula File-like structure in mollusks used to tear up food and
bring it into the mouth of an animal.
ROV “Remotely Operated Vehicle”
runoff Rainfall that is not absorbed by the ground and flows
into the ocean; usually carries with it pollutants like oil, fertilizers
and other materials.
scavenger Animal that feeds on dead plants or animals.
sediment Material that settles to the ocean bottom such as dirt,
dead microorganisms and pollutants.
stipe Stem-like part of seaweed.
vertebrate Animal that has a backbone.
siphonophore Colonial animal related to the jellies; they can
grow to be over 50 feet long.
Echinoderms Invertebrates with spiny skin, often in a star shape. zooplankton Microscopic animals that float in the ocean.
66
Natural History Museum of Los Angeles County
Books
Love, R. M. Probably More Than You Want to Know About the Fishes of the Pacific Coast.
Santa Barbara, CA: Really Big Press, 1991. ISBN 0-9628725-4-7
Macquitty, M. Eyewitness Books Ocean. London: Dorling Kindersley, 1995. ISBN 0-679-87331-7
Monterey Bay Aquarium Sea Searcher’s Handbook. Boulder, CO: Roberts Rinehart Publishers,
1996. ISBN 1-878244-15-9
Appendix C For More Information
Here are some other places where you (and your students) can find more information about
marine biology and ocean exploration, as well as ideas for more ocean-themed activities.
Niesen, T. M. Marine Biology Coloring Book. Oakville, CA: Coloring Concepts, Inc., 1982.
ISBN 0-06-460303-2
Nye, B. Bill Nye the Science Guy’s Big Blue Ocean. New York: Hyperion Books for Children,
1999. ISBN 0-7868-4221-0
Parker, S. Eyewitness Books Fish. London: Dorling Kindersley, 1990. ISBN 0-679-80439-0
Parker, S. Eyewitness Books Seashore. London: Dorling Kindersley, 1989. ISBN 0-394-82254-4
Web Sites
California Department of Fish and Game www.dfg.ca.gov
Environmental Protection Agency www.epa.gov
Long Beach Aquarium of the Pacific www.aquariumofpacific.org
National Wildlife Organization www.nwf.org/education
Oceanlink http://oceanlink.island.net
UCLA Ocean Discovery Center www.odc.ucla.edu
USC Sea Grant Program www.usc.edu/org/seagrant
Monterey Bay Aquarium www.mbayaq.org
Natural History Museum of Los Angeles County www.nhm.org
Natural History Museum of Los Angeles County
67
Resources
For More Information Appendix C
Echinoderm Photos Appendix D
The eight photos on the following pages can be used with the activity Invent a Key for Echinoderms.
Although the images are included in the Seamobile Teaching Kit that is provided to teachers
prior to the Seamobile visit, these prints can copied and used with other classes when the
teaching trunks are unavailable.
Appendix D Echinoderm Photos
Each team of students will require one complete
set of photos, species A through H.
Todd Winner
Randy Harwood
68
A
B
Natural History Museum of Los Angeles County
Natural History Museum of Los Angeles County
Appendix D Echinoderm Photos
Randy Harwood
D
Randy Harwood
C
69
Randy Harwood
Appendix D Echinoderm Photos
Rick Moffit
F
Natural History Museum of Los Angeles County
70
E
Natural History Museum of Los Angeles County
Appendix D Echinoderm Photos
Todd Winner
H
Randy Harwood
G
71
Additional Notes
Additional Notes
72
Natural History Museum of Los Angeles County