Download the Education Guide

Contents
Introduction …………………………………………………..…….
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Theme 1: Into the Deep ……………………………………..……
Exhibit Description ………………………………….....………
Key Concepts ………………………………………………….
Activity 1: Ocean Models and Map …………………………..
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Theme 2: The Deep Ocean ……………………………………...
Exhibit Description …………………….………………………
Key Concepts …………………………………….……….…..
Activity 2: Amazing Cephalopods!…….………………………
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Theme 3: The Dark Ocean ………………………………………
Exhibit Description …………………………………...……….
Key Concepts …………………………………………………
Activity 3: Deep-Sea Tag …...……...…………....................
Activity 4: Shrink It! ……………….……………………………
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Theme 4: Deep-Sea Destinations …………………….…..……
Exhibit Description ……………………………………...……
Key Concepts …………………………………….…………..
Activity 5: Create a Vent Animal ……………….……………
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(Note: Theme 4 in this Education Guide encompasses content from four
Deep-Sea Destination zones within the exhibition: Deep-Sea Canyons,
Abyssal Plains, Hydrothermal Vents, and Seamounts)
Theme 5: Deep Ocean Habitat ………………………………….
Exhibit Description …………………………………...………
Key Concepts …………………………………………………
Activity 6: Ocean Acidification Eggshell Experiment ……..
Appendix 1:
Appendix 2:
Appendix 3:
Glossary
Educational Resources and Websites
High Resolution Illustrations and Images
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Introduction
Take a journey to the most inaccessible ecosystem on Earth – the
deep ocean. It is a world more amazing and alien than anything
one can imagine. This vast environment contains the greatest
diversity of life, yet we have explored surprisingly little of it. It is
home to some of the strangest creatures living under some of the
most inhospitable conditions on the planet. It is a cold and dark
environment, where most of the animals communicate by light, and
the pressure is almost unimaginable for terrestrial creatures like us.
It is a world without plants, and some of the animals are some of
the largest that have ever lived.
The traveling exhibition Creatures of the Abyss takes visitors down
into the deep, across the vast seafloor, up submarine mountains,
into canyons, and alongside hydrothermal vents. It is a mysterious,
immersive and awe-inspiring glimpse into another world.
This Education Guide has been developed to accompany the
Creatures of the Abyss exhibition. It provides a tool for educators to
further examine the themes and concepts presented in the
exhibition through a series of “hands-on” classroom activities. It
introduces students to the dark and cold deep-sea environment, the
strange and amazing creatures that live there, the variety of deepocean habitats, and potential threats to our ocean.
This guide provides background information and science activities
suitable for students from Grades 5 to 8. The guide is divided into
five themes, corresponding to the themes of the exhibition. The
activities can be adapted and expanded as necessary to
complement course curricula.
Each theme begins with a description of the related exhibits and
key concepts. One or two activities are then described in a step-bystep format. These activities include experiments, demonstrations,
games, building activities, and research projects. Questions for
classroom discussion are provided at the conclusion of each
activity. This Education Guide also includes several appendices,
posted separately for ease of downloading and printing:
• new vocabulary words are underlined throughout this document
and defined in the glossary in Appendix 1;
• useful resources for further learning are listed in Appendix 2;
• high-resolution versions of many of the diagrams and
illustrations in this guide are provided as separate files in
Appendix 3.
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Education Guide – Grades 5 to 8
Theme 1: Into the Deep
Exhibit Description
Start your journey into the deep ocean – a very inhospitable place
for visitors like us! The entrance portal transports visitors into the
deep sea. As they descend from daylight into the dark abyss,
striking images illustrate some of the strange creatures that inhabit
these depths, and a soundscape introduces unique sounds of the
deep ocean. Beyond the entrance, visitors study a world map to
locate deep-sea destinations featured in the exhibit, control their
own virtual descent in the ocean depths at a computer station, and
rotate a column that represents the ocean profile to see how
temperature, pressure and light levels change with depth.
Key Concepts
The Earth contains one vast, interconnected ocean.
Although we give names to different ocean regions, there is really
only one ocean on Earth. The Atlantic, Pacific, Indian, Arctic and
Antarctic Oceans are all interconnected and can be called different
ocean “basins”. Ocean currents circulate water, nutrients and
pollution throughout the ocean. The ocean is the Earth’s dominant
feature, covering 70% of the Earth’s surface and providing 99% of
the available living space on the planet.
The ocean bottom is not flat.
The depth of the ocean varies considerably. The tallest mountains,
flattest plains and deepest valleys are located at the bottom of the
ocean. The Mariana Trench in the Pacific basin is the deepest
location (about 11 kilometers or more than 6 miles below the water
surface).
The ocean is deep, dark, cold, under pressure and largely
unexplored.
The ocean’s average depth is four kilometers (2.5 miles). Below
1,000 meters (3,280 ft), the environment is perpetually dark, and
the temperature is a constant 2°C to 4°C (36°F to 39°F) – there are
no daylight cycles and no seasons! With increasing depth, there is
also increasing hydrostatic pressure from the weight of all of the
water above. We know that the ocean is a vast environment
containing a great diversity of life. New species are discovered on
almost every dive, yet 95% of the ocean still remains to be
explored.
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Education Guide – Grades 5 to 8
The ocean contains five depth zones:
0 - 200 meters (0 – 660 ft)
Epipelagic Zone (Sunlit Zone): contains light
200 – 1,000 meters (660 – 3,280 ft)
Mesopelagic Zone (Twilight Zone): 99% of all light is filtered out
1,000 – 4,000 meters (3,280 – 13,120 ft)
Bathypelagic Zone (Midnight Zone): total darkness
4,000 – 6,000 meters (13,120 – 19,690 ft)
Abyssopelagic Zone (The Abyss): total darkness
6,000 – 10,924 meters (19,690 – 35,840 ft)
Hadalpelagic Zone (Deep-sea Trenches): total darkness
Activity 1: Ocean Models and Maps
Students will interpret a bathymetric map of the Earth’s ocean.
They will build models of seamounts and create cross-section
diagrams and bathymetric maps of their models. This is a group
activity.
Materials
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Bathymetric map of the Earth’s ocean (in Appendix 3)
Cross-section diagram of ocean depth zones (in Appendix 3)
Example of a topographic map
Play dough (see recipe on page 46)
Small 10 centimeter (4 in) rulers or sticks/straws with centimeter
or inch measurements
Square plastic containers - approximately 1 liter (1 quart) size
and at least 10 centimeter (4 in) in height
Clear plastic overhead transparencies
Waterproof markers
Small plastic funnels
Water
Introduction
Have students gather around a topographic map. Ask students to
explain what the contour lines represent on the map. Explain that
elevation is the height above sea level. Note that the shades of blue
represent depths below sea level of 0 – 200 meters (0 – 660 ft),
200 – 500 meters (660 – 1,640 ft), 500 – 1,000 meters (1,640 –
3,280 ft), 1,000 to 2,000 meters (3,280 – 6,560 ft), 2,000 to 3,000
meters (6,560 – 9,840 ft), and so on.
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Education Guide – Grades 5 to 8
Notice that the contours increase in elevation as you move inward
for a mountain and outward for a valley. Take an example mountain
from the topographic map and use the contours to draw a rough
cross-section diagram on the board. Explain that similar maps are
created for the ocean – these are called bathymetric maps.
Project a large image of the world bathymetric map (file “COTA
Theme 1_World Map” in Appendix 3). Review the legend. Explain
that this map uses colored contours to show the changes in depth
of the ocean.
Ask the students questions about the bathymetric map, such as:
1. How many oceans are there? (The correct answer should be
one; although names have been given to areas of the ocean, the
ocean is one interconnected body of water with many ocean
basins. Look up the “Ocean Literacy Network” on the web for
more information about this.)
2. How much of the Earth’s surface is covered by ocean?
(approximately 70%)
3. Is the seafloor flat?
o Where are the deepest areas of the ocean? (darkest
colored areas, where the deep-sea trenches are located)
o Where are the shallowest areas? (lightest colored areas;
for example, the continental shelves bordering the
continents)
4. Can you point to an undersea mountain, called a seamount?
What do you notice about some of the seamounts? (Some are
associated with volcanic island chains; use Hawaiian Ridge as
an example.)
5. Can you point to an abyssal plain? What do you notice about
the size and depth of abyssal plains? (They are represented by
large areas of the same color – a uniform depth over a broad
area.)
6. What do you notice about the depth contours? How does a
bathymetric map differ from a topographic map? (The
bathymetric map shows depth below sea level rather than
elevation above sea level; contours decrease in depth as you
move inward on a seamount, whereas contours increase in
elevation for a mountain on a topographic map.)
Project the cross-section diagram (file “COTA Theme 1_Ocean
Depth Zones” in Appendix 3). Review the names and depth zones
of the ocean with the students. Notice that light cannot penetrate
much below 200 meters (660 ft), so the deeper zones are in total
darkness all the time. Explain that the ocean is deep, dark and cold.
Since the ocean is a three-dimensional environment, it provides
99% of the available living space on the Earth and contains an
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Education Guide – Grades 5 to 8
abundance of unique creatures. Despite years of research, about
95% or more still remains to be explored.
See Appendix 3, file “COTA Theme 1_Ocean Depth Zones” for
diagram in larger size and higher resolution.
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Education Guide – Grades 5 to 8
See Appendix 3, file “COTA Theme 1_World Map” for world
bathymetric map in larger size and higher resolution.
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Education Guide – Grades 5 to 8
Activity
Teacher Preparation:
1. Project a large copy of the bathymetric map and ocean depth
zone diagram from Appendix 3 of this guide.
2. Prepare several batches of play dough using the recipe at the
back of this guide.
3. If you are not using rulers, make sticks or straws with
measurement increments marked on them.
4. Divide the students into groups of 2 or 3.
Procedure:
1. Build a seamount structure with play dough that extends up to
3/4 of the height of the container. The seamount should be built
in the center of the container and there should be space around
the base of the seamount on all sides. Encourage the students
to create a jagged, unsymmetrical structure, similar to what
would be found in nature. Note that some seamounts, like Bear
Seamount, are flat-topped.
2. Use a ruler to draw a scaled, cross-sectional diagram of the 3dimensional model.
3. Place the ruler against one side of the container with the highest
number at the bottom of the container. Tape the ruler in place,
keeping the ruler vertical and the measurement lines visible.
4. Cut the overhead transparency into a square that fits the
dimensions of the top of the container. Cut away a small piece in
one corner to fit the funnel spout. Tape the overhead
transparency to the top of the container and insert the funnel in
the corner.
5. Look down at your model from directly above, through the
overhead transparency. Use a waterproof marker to trace a
contour line on the transparency that represents the base of the
seamount where it touches the bottom of the container. Label
this contour line with the depth of the container as shown by the
ruler.
6. Slowly add water to the container using the funnel until the
water depth is 1 cm (or 1/4 in) from the bottom.
7. Look down on your model from directly above again. Trace a
contour line where the water intersects the seamount. Label the
contour line with the water depth shown on the ruler.
8. Repeat Steps 6 and 7 until the seamount is completely
submersed in water. You have created a bathymetric map of
your structure. To finish the map, add a legend, including the
contour interval (difference in depth represented by the contour
lines). Decide on a name for your seamount, and use it for the
title of your map.
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Education Guide – Grades 5 to 8
Variation:
Instead of using water to fill the container and trace the contour
lines, have students collect depth measurements and plot a
bathymetric map. To do this, follow the instructions below.
1. Make a grid on the overhead transparency, labeled with letters
across the top and numbers down the side.
2. Punch small holes in the transparency at the center of each grid
box.
3. Prepare a datasheet with the same grid and labels. Create a
legend on the datasheet where each 0.5 centimeter (or 1/4 in)
depth range is represented by a different color (i.e., 7.5 to 8.0
cm = green; 7.0 to 7.5 cm = yellow). It works best if the colors
are selected so the greater depths are represented with darker
colors and shallower depths by lighter colors.
4. Make a ruler out of a straw or stick with 0.5 cm (or 1/4 in)
divisions.
5. Insert the straw or stick with the lowest number at the bottom
into a hole and make sure it goes straight down until it contacts
the model, but not poke into the model.
6. Read the depth measurement on the straw at the hole in the
transparency. Based on the depth measurement, determine the
appropriate color to fill in that square on the datasheet.
7. Continue until all of the holes in the grid have been sampled.
You have created a color contour bathymetric map of your
structure, based on measurements taken from the water
surface.
Discussion
What are some key properties of the deep ocean?
Answers: deep; dark; cold; under intense pressure; all one
interconnected ocean; varied depth and bathymetry (for example:
seamounts, deep-sea canyons, trenches, abyssal plains).
How much do we know about the biology of the deep ocean?
Relatively little - only 5% of the deep ocean has been explored to
date. New species are constantly being discovered or described.
How are bathymetric maps developed?
Two main methods have been used to map the ocean’s floor and
its depth. Originally, people physically dropped long lines down to
the seafloor to determine depth. In the 20th century people began
using sonar to do single-beam echo sounding. Sonar is a technique
that uses sound waves bounced off the seafloor. A pulse of sound
is directed from a ship downwards through the water. When the
sound pulse contacts an object, it produces an echo signal that
travels back up to the ship. The time it takes for the echo signal to
be received is converted into a depth measurement for that location
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Education Guide – Grades 5 to 8
(the speed of sound in water is approximately 1,500 meters/second
(5,000 ft/second), but it varies depending on temperature, pressure
and salinity). The ship takes many data points, which are plotted to
develop bathymetric maps. The recent development of multibeam
bathymetry allows people to map wider “swaths” of the seafloor at a
time, rather than the single narrow lines produced by single-beam
echo sounding.
Which may be more accurate – topographic maps or
bathymetric maps?
Bathymetric maps are more challenging to produce because we
cannot see the bottom of the ocean and have to rely on equipment
to do the measurements. For this reason, bathymetric maps may
not be as accurate as topographic maps. The accuracy of either
type of map increases with the number of data points measured.
Multibeam bathymetry can produce bathymetric maps that are
accurate to within about 10 meters (33 ft). As the technology used
to measure the depth of the ocean floor improves, the accuracy of
bathymetric maps also improves.
References
This activity was adapted from:
NOAA Ocean Explorer, Section 2 Mapping the Ocean Floor:
Bathymetry
http://oceanexplorer.noaa.gov
A good reference about single-beam echo sounding and multibeam
bathymetry from the Woods Hole Oceanographic Institution:
http://www.divediscover.whoi.edu/tools/sonar.html
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Education Guide – Grades 5 to 8
Theme 2: The Deep Ocean
Exhibit Description
Encounter some sensational creatures, some of which freely roam
from the depths to the surface and back again in amazing
migrations or in search of prey. A life-size model of a colossal squid
– seen against the silhouette of its predator, the sperm whale –
dominates this thematic exhibit area. At the surrounding exhibits,
visitors can explore a remarkable class of creatures, the
cephalopods, which are distributed in all ocean basins and at every
depth. The exhibit focuses on squids and octopuses, which are the
cephalopods found in the deep ocean.
Key Concepts
The deep ocean contains a wide variety of uniquely adapted
creatures.
Between the surface of the ocean and the seafloor lies the largest
habitat on Earth. The deep, open ocean contains an abundance
and variety of life. Creatures of all sizes make the deep ocean their
home, from the tiny barreleye to the huge colossal squid and sperm
whale. Each of these creatures has unique adaptations (such as
coloration, physical features or behavior) that allow them to hunt,
hide, reproduce, and control their depth in a fluid world without any
walls. In the vast open water, there is nothing to rest upon, hide
behind, or use as a landmark. At any time, a predator can attack
from any direction – not only from each side, but from above and
below as well.
1) Cephalopods
Cephalopods are a class of invertebrates whose heads merge
directly with their arms. They are carnivorous, and have a horny
beak to slice their prey. Most of the cephalopods in the deep sea
are squids and octopuses. All octopuses have eight arms, while
squids generally have eight arms and two tentacles. The average
lifespan of a cephalopod is surprisingly short – less than three
years. The strategy is to grow fast, reproduce, create many
offspring, and die young. Larger species, such as the giant squid,
may live for about five years. Cephalopods have many adaptations
including:
• Intelligence: Squids and octopuses have the largest brains of
all the invertebrates. Their highly developed eyes and other
sensory organs take in a vast amount of information, which
requires a big brain to process. This intelligence contributes to
their success as predators.
• Vision: The colossal squid has the largest eyes in the animal
kingdom. In the darkness of the deep, they are well adapted to
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Education Guide – Grades 5 to 8
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detect faint light emitted by other creatures. They even have
organs that emit their own bioluminescent light. Squid and
octopus eyes have similar features to human eyes. Although
many do not see in color, they can see fine detail and even see
polarized light.
Camouflage: Shallow water octopuses and squids have
amazing abilities to change their posture, and the color and
texture of their skin. Species that live in the perpetual blackness
of the deep can use different methods of camouflage to blend
into their surroundings. Some deep-sea squids and octopuses
are red-colored or transparent so that they are difficult to see in
dim blue light or complete darkness. Some create their own
bioluminescent light to distract or confuse predators.
Locomotion: Squids and octopuses propel themselves with a
variety of methods in the deep. Some use their arms to crawl
along the bottom or move through the water. Some wave or flap
fins on the sides of their mantles to “fly” through the water.
When they need a burst of speed, they use jet propulsion. To
propel themselves using jets of water, they suck water into their
mantle, and squeeze it out through their tube-like siphons. Like
air being let out of a balloon, this high-powered jet propels them
rapidly through the water.
Ink: Most shallow-water squids and octopuses squirt ink to
defend themselves from predators. The ink acts like a smoke
screen or decoy, confusing the predator as the creature
escapes. Some transparent squids inject ink into their mantle
cavities to help them disappear into the blackness. In the total
darkness of the deep ocean, many species still use ink, but
researchers are still puzzling out how dark ink is useful in the
blackness.
Beak: Squids and octopuses have a beak at the center of their
arms where their mouth is located. It is made of chitin, similar to
the material in your fingernails. Strong muscles move the two
parts of the beak to slice prey into “bite-size” pieces.
Arms and tentacles: Both squids and octopuses have eight
arms. However, squids have two additional specialized arms
called tentacles, and squids’ appendages can be equipped with
suckers, toothed rings and hooks. Surrounding the suckers are
sensory cells that provide the animal with information about its
prey and its surroundings.
2) Sperm Whale (Physeter macrocephalus)
With adult males reaching a length of about 16 meters (52 ft),
sperm whales are the largest of all toothed whales. Found globally,
they commonly dive to 400 meters (1,300 ft), but can go at least as
deep as 1,000 meters (3,300 ft). In Antarctic waters, a big male’s
primary prey is the colossal squid. Sperm whales dive deep and
can hold their breath for over 60 minutes. In darkness they search
for and detect their prey using sound waves, called echolocation.
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Education Guide – Grades 5 to 8
Echolocation reveals the distance, movement, shape and texture of
objects.
3) Creatures of the Water Column
Many strange and fascinating creatures can be found throughout
the water column of the deep ocean. The ocean’s open water
contains a variety of different sized creatures with a wide range of
adaptations and strategies for obtaining food and protecting
themselves. These creatures live all or part of their life in open
water, and are not associated with any surface such as the
seafloor.
Representative creatures featured in the exhibit include:
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Giant larvacean: Larvaceans are small, tadpole-like creatures
that create elaborate mucus structures to capture food particles
from the surrounding seawater. Each day these sticky filter
structures get clogged with organic matter, and new ones are
built. The falling structures, called sinkers, carry large amounts
of carbon to the seafloor.
Longnose lancetfish: One of the largest midwater predators,
lancetfish slice through large prey with their curved, blade-like
teeth. A sail-like fin helps them maneuver and turn rapidly. To
make it easier to find a mate, each fish has both male and
female sex organs.
Cock-eyed squid: Swimming on an angle in the mesopelagic
twilight, a probing eye searches for food above, and a smaller
eye monitors for danger from below. As part of the largest
migration on the planet, these squids travel from deep waters to
the surface to feed each night.
Vampire squid: This is the only squid to live its whole life in the
oxygen minimum layer of the ocean. To conserve energy, it
swims by flapping its fins while dragging two tendrils behind that
may sense prey crossing its path. Vampire squids have
bioluminescent organs on their arm tips, two large
bioluminescent patches on their mantles, and other small
bioluminescent spots.
Big red: Big red is a very large, red and unusual jellyfish. It has
no stinging tentacles around its bell, so it grasps its prey with its
four to seven fleshy arms. Big red was identified as a new
species in 2003.
Glowing sucker octopus: Glowing sucker octopuses swim by
flapping their fins or moving like a jellyfish, which is more energy
efficient than jet propulsion. Their suckers cannot grasp but they
can produce bioluminescent light, which is something very
unusual for octopuses.
Fishing siphonophore: A siphonophore is a collection of
jellyfish-like creatures that function as a single animal. Many
siphonophores have stinging tentacles and wait for prey to pass
Education Guide – Grades 5 to 8
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by, but Erenna is unusual because it may also “fish” for prey
using red, glowing lures – an unusual color for bioluminescence!
Johnson’s black anglerfish: The female anglerfish sits and
waits for her food in an environment where prey may be scarce.
The bioluminescent, glowing lure on her head attracts prey, and
possibly mates. Her stomach is very stretchy, to accommodate
creatures very near her own size.
Barreleye: The barreleye fish has been known since 1939, but
the delicate, transparent shield covering its eyes was only
discovered in 2004. Its eyes can rotate forwards or upwards
within the protective shield, and may allow the fish to raid the
stinging tentacles of jellies for trapped prey.
Activity 2: Amazing Cephalopods!
Students will learn about the amazing adaptations of cephalopods
that make them well suited to their deep ocean environment. This
activity is intended to be completed while students are touring The
Deep Ocean exhibit, which is centered around the model of the
colossal squid in Creatures of the Abyss. Students will use the
exhibit to answer questions about cephalopods and other creatures
of the water column featured on the “sperm whale wall”. This
activity can be completed individually or in pairs.
Materials
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Student Discovery Sheets (see below)
Teacher Answer Sheet (see below)
Pens
Introduction
Ask the students what types of creatures live in the ocean. Make a
list on the board. Identify which of these creatures are likely to live
near the surface (in the Epipelagic Zone) and which of these
creatures may live in the deep ocean.
Ask the class if they know what a cephalopod is. Explain that
Cephalopoda is a class of invertebrate animals that include squids
and octopuses. Ask the students to describe some of the features
of squids and octopuses and list them on the board. Review the
concept of adaptations. Explain that cephalopods have many
special adaptations that allow them to live in the deep ocean where
food is scarce and it can be difficult to hide from predators. Review
some of the special adaptations of cephalopods, including
intelligence, good vision, mimicry and camouflage, various modes
of locomotion, beaks, ink, arms and tentacles.
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Education Guide – Grades 5 to 8
Explain that the students will be visiting the Creatures of the Abyss
exhibition and that they will be given a Discovery Sheet to complete
while viewing The Deep Ocean exhibit zone. Through this activity,
the students will gain an understanding of the unique adaptations of
cephalopods and other deep-sea creatures. Explain that they can
find all the answers by doing the activities, using the touch-screen
computer interactive exhibits, and studying the graphics in The
Deep Ocean area, which is centered around the colossal squid
model and sperm whale wall.
Activity
Teacher Preparation:
• Photocopy student Discovery Sheets.
• Arrange for approximately 30 minutes of time for students to
complete the Discovery Sheets during their visit to the
exhibition.
Procedure:
• Using The Deep Ocean exhibit zone as a source of information,
answer the questions on the student Discovery Sheet. All of the
answers can be found in the interactive exhibits, touch-screen
computers, and graphics.
Discussion
What was the most interesting thing you learned about
cephalopods? Why?
What do you notice about the size of deep-sea creatures?
Deep-sea creatures vary considerably in size. Some are extremely
large, such as the colossal squid and sperm whale, while others are
very small, such as the barreleye fish and Johnson`s black
anglerfish.
What are the biggest challenges for deep-sea creatures? What
are some common adaptations to overcome these challenges?
In order to survive, all animals must find a way to obtain food, hide
from predators and reproduce. The challenge for deep-sea
creatures is to do all of these things in absolute darkness and with
few places to hide. Bioluminescence is one of the key adaptations
many deep-sea creatures have to allow them to see and attract
prey and mates. Bioluminescence may also be used as
camouflage. Many creatures have sensing structures, such as
arms, tentacles or suckers, to help them find and capture prey in
the dark. Camouflage is used by many species to hide from prey in
the absence of physical cover.
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Education Guide – Grades 5 to 8
Amazing Cephalopods!
Student Discovery Sheet
Cephalopods
1. What is the literal translation of the term “cephalopod”?
Why is this word appropriate for animals such as squids and
octopuses?
2. What material is a cephalopod beak made of?
3. What are some reasons why squids and octopuses release ink
clouds?
4. What cephalopod has the largest eyes in the animal kingdom?
5. What are three ways cephalopods can move?
6. How does the Dumbo octopus usually move? Why?
7. Which is the “larger” animal – the colossal squid or the giant
squid? Explain.
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Education Guide – Grades 5 to 8
8. How do researchers know that cephalopods have high
intelligence?
9. Which cephalopod body part cannot be squeezed to fit through
small spaces?
10. What is the function of squid tentacles?
11. How can cephalopods camouflage themselves in shallow
water?
12. What is the main function of suckers on the arms and tentacles
of cephalopods? How might suckers be used for locomotion?
13. In order for a colossal squid to move by jet propulsion, which
structure must it expand to draw water in?
Which structure is used to release the water?
14. What shape is a squid’s brain?
15. Describe how colossal squids catch and hold their prey.
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Education Guide – Grades 5 to 8
Creatures of the Water Column
16. Find the life-sized graphic cutouts of three featured species of
open water cephalopods: vampire squids, cock-eyed squids and
glowing sucker octopuses. Compare and contrast these species.
How do their physical features differ? What unique adaptations
do each of them have for detecting their prey?
17. Which creature can expand her stomach to eat prey almost as
large as herself?
18. Which of the open water species have bioluminescent lures?
What do they use them for?
19. How deep can a sperm whale dive?
20. How do sperm whales find their prey?
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Education Guide – Grades 5 to 8
Amazing Cephalopods! Teacher Answer Sheet
Cephalopods
1. “Head-foot”. It is appropriate because their heads are directly
attached to their arms.
2. Chitin. Pronounced “kite-in,” it is the same material as in the
hard parts of insects.
3. The ink clouds can be used to hide in or escape behind, so that
the creature cannot be seen by its predator.
4. Colossal squid.
5. Jet propulsion, fin swimming, and crawling and walking along
the ocean floor.
6. The Dumbo octopus usually moves by flapping its fins or pulsing
its webbed arms. It does this to conserve energy. These
movements use much less energy than jet propulsion.
7. The colossal squid is heavier and bigger around, but the giant
squid is longer.
8. Laboratory studies have shown that cephalopods have the
ability to problem solve. They can learn and remember
information and use it later. They are curious about their
surroundings. They have the ability to assess objects and
determine how to use them to create things, such as shelters.
9. The beak because it is made of hard chitin.
10. Tentacles are used to actively seize (grab) prey, and to obtain
information about the squid’s environment. You can see a squid
use its tentacles to grab a fish and bring the prey to its mouth in
the video at the Cephalopod Beaks exhibit. This is not covered
in the signage, but many deep-sea squids let their very long
tentacles dangle in the water, like fishing lines, to wait for prey to
pass by.
11. Cephalopods can control their posture, and the color and
texture of their skin, to blend in with their surroundings. Muscles
surrounding special sacs of dye, called chromatophores, expand
or contract to change the color of the skin.
12. Suckers enable squids and octopuses to grab and hold onto
things, and to bring prey to their mouths. They also contain
sensory cells that provide animals with information about prey
and their surroundings. Some cephalopods also use their
suckers to help them grip the substrate when they walk along
the ocean floor. An interesting fact is that the glowing sucker
octopus has bioluminescent suckers that can no longer grip
things, but may be used to lure prey.
13. The mantle is expanded to draw water in through an opening
around the head, and the siphon is opened to release the water.
14. Donut-shaped. The squid’s esophagus (throat) passes through
the middle of its brain.
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Education Guide – Grades 5 to 8
15. Colossal squids have suckers with toothed rings, and sharp
hooks on their arms. They also have swiveling hooks on their
tentacles. The suckers are used to grab their prey and the hooks
dig into the prey to prevent its escape.
Creatures of the Water Column
16. The cock-eyed squid is smaller than the other species and has
two different sized eyes - a large eye for probing the waters
above it for prey, and a smaller eye to look out for danger from
predators below. The vampire squid and glowing sucker octopus
have webbed arms. The vampire squid drags two tendrils
behind to sense prey crossing its path. The glowing sucker
octopus produces bioluminescent light in its suckers to help it
find prey.
17. The female Johnson’s black anglerfish.
18. Fishing siphonophore and Johnson’s black anglerfish. They
both use their bioluminescent “lures” to attract prey, and
anglerfish females probably use them to attract mates.
19. Sperm whales commonly dive to 400 meters (1,300 ft), but can
dive to at least 1,000 meters (3,300 ft) and probably deeper.
20. Sperm whales search for and detect their prey using sound
waves, called echolocation. Echolocation reveals the distance,
movement, shape and texture of objects.
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Education Guide – Grades 5 to 8
Theme 3: The Dark Ocean
Exhibit Description
The average depth of the world’s ocean is about 4,000 meters
(13,000 ft). In the deep sea, no light penetrates from above. It is
pitch dark, under intense pressure from the weight of all of the
water above, and persistently cold – always within the range of 2°C
to 4°C (36°F to 39°F). The animals that thrive there have special
adaptations that allow them to live under these extreme conditions,
and find prey and avoid predators.
Visitors experience the cold temperature, learn about light
penetration, and see the effects of the intense pressure at the
Deep-Sea Sensations exhibits. In the Bioluminescence Theater,
they view some of the amazing light patterns created by creatures
that live in total darkness. They become a bioluminescent creature
by donning a specially painted vest and entering a darkened blacklight area, where their glow pattern is revealed. They follow the
history of deep-sea exploration through a graphic timeline that
showcases the milestones of discovery from the mid-1800s to
present day.
Key Concepts
The deep ocean is dark.
There is very little light in the ocean. As you dive deeper, sunlight
cannot penetrate through all of the water. The deeper you go in the
ocean, the darker it gets. If you go really deep, there is no light at
all – it is completely black.
Not only does the amount of light change as you go deeper in the
ocean, but the color of the light changes. Sunlight contains all the
colors (wavelengths) of white light, but each color penetrates to a
different depth. Blue light travels the furthest through seawater – it
is the only color of light that penetrates below the top 200 meters
(660 ft) of the sea. The other colors are scattered or absorbed at
shallower depths. Below about 10 meters (30 ft), there is no red
light. Below about 100 meters (330 ft), there is no green light.
In the pitch-blackness of the deep sea, about 90% of the creatures
make their own light by bioluminescence. This light is created by
chemical reactions in their bodies. Bioluminescent light can be used
to attract prey or a mate, to frighten predators, or for camouflage.
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Education Guide – Grades 5 to 8
See Appendix 3, file “COTA Theme 3_Light” for larger version of
this diagram at higher resolution.
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Education Guide – Grades 5 to 8
The deep ocean is under intense pressure.
Creatures in the deep ocean are under incredible pressure from the
weight of all the water above them. At 4,000 meters (13,120 ft), the
average depth of the world’s ocean, the pressure is about 400
atmospheres or 400 times greater than at surface. Here, the water
exerts about 400 kilograms of force on each square centimeter
(5,690 pounds of force per square inch) of a creature’s body. That’s
like having an adult horse stand on your thumbnail!
See Appendix 3, file “COTA Theme 3_Pressure” for larger version
of this diagram at higher resolution.
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Education Guide – Grades 5 to 8
The deep ocean is very cold.
There are no seasons in the deep ocean, just a year-round
temperature of 2°C to 4°C (36°F to 39°F). Regardless of the
surface-water temperature, the temperature of the deep ocean
remains constant. At mid latitudes, surface-water temperature
varies considerably depending on location, time of day, season,
and weather. Just below this warmer surface layer lies the
thermocline, a layer where temperature drops very rapidly with
depth. Beneath the thermocline, the temperature of the deep water
is stable at 2°C to 4°C (36°F to 39°F).
See Appendix 3, file “COTA Theme 3_Temperature” for larger
version of this diagram at higher resolution.
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Education Guide – Grades 5 to 8
Activity 3: Deep-Sea Tag
Students will explore the properties of light, color and
bioluminescence in the deep ocean by wearing special “deep-sea
goggles” and attempting to find different colored prey in the dark.
This activity includes two parts that can be conducted over two
days. Part 1 can be completed as a class activity or in groups. Part
2 is a class activity.
Materials
• 3 x 5 inch index card with a slit cut in the middle: length of slit
approximately 2.5 cm (1 in) and width of slit about 0.3 cm (1/8
inch)
• Slide projector and screen (or white board/white wall)
• Glass prism
• Glow stick
• Clear blue plastic sheets (overhead plastic or report covers), cut
into strips approximately 21 cm (8.5 in) long by 7.5 cm (3 in)
wide
• Large rubber bands, approximately 30 cm (12 in) long
• Binder or “alligator” clips (black and silver clips for holding
bundles of paper)
• Craft foam or felt in red, orange, yellow, green, blue and black
colors, cut into 2.5 cm (1 in) square pieces; at least 4 squares of
each color
• Black poster paper or construction paper
• Flashlight
• Plastic bags
• Tongs
• Timer
Introduction
Explain that sea creatures look a lot different in the deep ocean
than they would at the surface. At the surface, there is bright light
from the sun and we can see all the colors of the visible spectrum
(the colors of a rainbow). However, sunlight cannot penetrate very
far into the water. As you go deeper, it gets darker and darker until
it is pitch black in the deep ocean.
Show the class the diagram of light penetration with depth (in “Key
Concepts” section above; larger version in Appendix 3, file “COTA
Theme 3_Light”). Sunlight contains all the colors (wavelengths) of
white light, but each color penetrates to a different depth. Blue light
travels the furthest through seawater – it is the only color of light
that penetrates below the top 200 meters (660 ft) of the ocean. The
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Education Guide – Grades 5 to 8
other colors are scattered or absorbed at shallower depths. For
example, below 10 meters (33 ft), there is no red light, and below
100 meters (330 ft), there is no green light.
Ask the students to describe the challenges of trying to find a small
red sock in a dark closet with a dim blue flashlight. First, everything
would be dark, so it would be hard to distinguish shapes of objects.
Secondly, the blue light would make it difficult to distinguish the
colors of objects.
Use the slide projector, index card and prism to project a visible
spectrum onto the screen or white board. To do this, hold the index
card with the vertical slit in front of the projector light and shine the
light through the prism. The light will come out of the prism on a
slight angle, so you will have to angle the projector light slightly
away from the screen or white board where you want the spectrum
to be displayed.
Explain that white light is made up of the colors of the rainbow –
this is called the visible spectrum. Ask the students to list the colors
of the visible spectrum in the order they appear (from outside to
inside, the colors are red, orange, yellow, green, blue, indigo and
violet). Objects appear a certain color because they reflect that
color and absorb all other colors. For example, a red object
appears red because it reflects red light and absorbs all other
colors. White objects appear white because they reflect all colors of
the visible spectrum. Black objects absorb all colors. Ask the
students if they feel cooler on a sunny day if they are wearing
white, or black?
Ask the students what they think will happen if you shine a blue
light through the prism, instead of the white light. Hold a piece of
blue plastic over the light source on the projector and ask the class
what colors they see. They should see only blue because the blue
plastic absorbs the other colors of light and reflects blue light.
Ask the students to hypothesize what color a red fish will appear if it
is swimming at the ocean surface. (Answer: it will appear red.)
What color will it appear to be 10 meters (33 ft) or more below the
surface? (Answer: it will appear black, and will be hard to see
because there is no red light to reflect and it will absorb all other
colors of light.)
Explain that the students are going to conduct an experiment to see
what different colors would look like under dim, blue light.
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Education Guide – Grades 5 to 8
Part 1: Color Perception in the Deep Ocean
Teacher Preparation:
1. Make one set of “deep-sea goggles” per student: Clip the black
part of a binder clip on each of the short ends of one strip of
blue plastic. To make the goggle straps, attach one end of the
rubber band to a loop of one binder clip and the other end of the
rubber band to a loop of the other binder clip. This is a basic set
of goggles. Additional layers of blue plastic can be added by
stacking them on top of the initial strip of blue plastic and reattaching the binder clips.
Procedure:
1. Place the black paper on the floor. Randomly place the colored
squares on top of the black paper.
2. Explain that the black paper represents the darkness of the
deep ocean and the colored squares represent deep-sea
creatures. Explain that the students will be putting on special
goggles that have blue lenses to simulate what they would be
able to see in the deep ocean where only blue light penetrates.
They will be adding more layers of plastic to simulate going
deeper in the ocean.
3. Make the classroom as dark as possible by turning off lights and
closing window blinds. Explain that the dark classroom
simulates the darkness of the deep ocean.
4. Ask each student to put on his or her goggles. One by one, they
should take turns picking up a colored square. They cannot feel
for the squares or peek around the goggles. They must be able
to see the square through the blue goggles.
5. When everyone has had a turn, remove the goggles and look at
the colors of squares that were picked up. Make a list of the
colors.
6. Give students another strip of blue plastic and show them how
to add the plastic to their goggles. Replace the colored squares
on the black paper.
7. Repeat Steps 4 and 5 with the two-layer blue goggles. Continue
adding layers to the goggles until only blue squares are visible.
8. Introduce the concept of bioluminescence using the glow stick.
Snap the glow stick to start the chemical reaction and create
light. Explain that in the deep ocean, some animals can create
their own light to help them see in the dark.
9. Have the students put on their goggles (with the maximum
layers of blue plastic). Can they see more squares of color with
the light of the glow stick than they could without?
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Education Guide – Grades 5 to 8
Part 2: Deep Sea Tag
Teacher Preparation:
1. Clear an area for playing deep-sea tag or use a gymnasium or
empty classroom.
2. Spread many pieces of black paper around the room and
randomly place colored squares (these will be “prey”) on each
paper.
3. Darken the room as much as possible.
4. Make enough “deep-sea goggles” for one team.
5. Cover the light end of three flashlights with a single layer of blue
plastic and place the flashlights next to three of the black
papers.
6. Divide the class into two teams: one team will be the “shrimp”;
the other team will select one member to be the “viperfish”, a
predator of the shrimp.
Procedure:
1. Before entering the classroom or gymnasium where the game
will be played, all members of the shrimp team should put on
their “deep-sea goggles”. Give each shrimp a plastic bag and a
set of tongs.
2. The second team should select one person to be the viperfish.
3. Explain the rules of the game. The shrimp have 10 minutes to
pick up as many prey items (i.e., colored squares) as possible.
They must keep their goggles on at all times and their hands
cannot touch the prey items. The prey items must be picked up
with the tongs and put in their plastic bag. The prey items must
not be pushed off the black papers onto the surrounding floor.
There are three blue flashlights/glow sticks (representing
bioluminescent lights) spread randomly throughout the room. If
you find a light, you may use it to help you find your prey. The
viperfish is a predator of the shrimp. But since you are a shrimp
and so well disguised, the viperfish can only see you if you
become bioluminescent. When you are using a flashlight or glow
stick, you are bioluminescent and the viperfish may tag you. If
you are tagged, you have been eaten and must go sit down.
When the timer goes off, all of the remaining shrimp must
freeze. The members of the other team (except the viperfish)
can sit on the sidelines and watch, but they must not say
anything to disturb those playing the game.
4. At the conclusion of the game, each person should record the
number and color of prey items collected.
5. Switch teams and repeat the game again.
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Education Guide – Grades 5 to 8
Discussion
Part 1: Color Perception in the Deep Ocean
Were any colors not visible with all of the goggles?
Black.
Which colors became not visible first as the blue color of the
goggles got darker?
Black, then red, then orange, then yellow.
If you were a fish trying to hide from a predator in the twilight
zone, called the Mesopelagic Zone, what color(s) would be the
best camouflage?
Black, then red.
How did the glow stick help you find more colored squares?
It provided more light.
What color of bioluminescence would be the best?
Blue, because it penetrates the furthest distance through the
seawater. Blue is the most common color of bioluminescent light,
but some creatures create other colors such as red, green and
yellow.
Why might animals need a light to see in the deep, dark
ocean?
To find or attract their prey, to attract a mate, to startle a predator,
or to escape from a predator.
Jellyfish are transparent, but some have red stomachs. Why
would they have a red stomach if you can see through them
anyway?
The prey that jellyfish eat is colored, so when the prey goes into
their stomach, the red color of the stomach camouflages the
stomach contents.
Part 2: Deep Sea Tag
Review the results of each game. Which individual shrimp collected
the most prey items? Which viperfish ate the most shrimp? What
were the most common colors of prey items collected? What were
the most challenging aspects of the game?
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Education Guide – Grades 5 to 8
References
This activity was adapted from:
NOAA Ocean Explorer, Section 5 Ocean Zones
(http://oceanexplorer.noaa.gov) “All that Glitters”
(http://oceanexplorer.noaa.gov/explorations/02sab/background/edu/
media/sab_deep_sea.pdf) and “Light at the Bottom of the Deep,
Dark Ocean” (http://www.usc.edu/org/coseewest/MidwaterRealm/10LightAtTheBottom.pdf).
Activity 4: Shrink It!
Students will explore the relationship between water depth and
hydrostatic pressure, and discover what happens to air-filled
objects under pressure. They will shrink Styrofoam cups using hot
steam in a pressure cooker. Due to safety issues, this activity
should be conducted as a teacher demonstration.
Materials
• Styrofoam drinking cups
• Pressure cooker
• Water
• Hot plate
• Timer
• Tongs
Introduction
Ask the students to imagine that they are holding a glass of air in
one hand and a glass of water in the other hand – which weighs
more? The glass of water weighs more because water is heavier
than air. The heavier a substance is, the more pressure it can exert
on an object.
Ask the students where pressure is likely to be the strongest – at
the top of the glass of water or at the bottom. Hydrostatic pressure
is highest at the bottom because of the weight of water above it.
Ask the class to imagine what the pressure would be like in the
deep ocean, thousands of feet below the surface. Creatures that
live in the deep sea are under incredible pressure from the weight
of all the water above them. Show the students the diagram
showing water pressure and depth (in “Key Concepts” section
above and in Appendix 3, file “COTA Theme 3_Pressure”).
Ask the class to hypothesize what will happen to a Styrofoam cup
under high pressure.
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Education Guide – Grades 5 to 8
Activity
Teacher Preparation:
1. Ensure that you have read and understand the operating
instructions that came with your pressure cooker, including all
safety precautions.
2. Prior to the demonstration, shrink a cup by heating it in the
pressure cooker for about 1 hour. See instructions below. Test
the time necessary ahead of time, as pressure cookers vary.
Procedure:
1. Ask a student to measure the height of a Styrofoam cup, and
the diameter of its base. Record the measurements.
2. Put a small amount of water in the bottom of the pressure
cooker. Use approximately 1 to 2 cm (1/2 inch) of water.
3. Place a Styrofoam cup into the pressure cooker.
4. Seal and lock the lid on the pressure cooker and place it on the
heating plate. Turn on the heat source and heat for 20 to 30
minutes. (Note that this is a shorter heating time than for the cup
prepared ahead of time.) Open the lid and use tongs to remove
the shrunken cup.
5. Ask a student to measure the height and base diameter of the
shrunken cup. Compare to the original cup measurements.
6. Show the class the cup that you shrunk before class, but don’t
tell them what you did to create it. Ask a student to measure the
height and base diameter of this cup and compare to the others.
Ask the students to hypothesize why this cup is smaller than the
one that was shrunk in class.
7. Place a chair next to a table. Ask a student to arrange the cups
in the order you would find them in the ocean. One cup should
be placed on the table (representing the surface ocean), one on
the chair (representing the Midwater zone of the ocean), and
one on the floor (representing the deep ocean).
Discussion
Why did the cup shrink?
The intense pressure of the water vapor (gas phase) within the
pressure cooker compressed the air spaces within the Styrofoam.
Remember that in this experiment, water vapor was used to create
pressure, rather than liquid water.
Why was the teacher’s cup smaller than the one shrunk in the
classroom demonstration?
It was under pressure for a longer period of time and the pressure
in the pressure cooker increased, compressing the Styrofoam to a
greater degree.
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Education Guide – Grades 5 to 8
What is the relationship between water pressure and depth in
the ocean?
Water (hydrostatic) pressure increases with depth because of the
increased weight of the water above.
How do deep-sea creatures survive under such high water
pressure? Could humans survive under the same water
pressure?
Creatures in the deep ocean are adapted to live under great
pressure. They are composed largely of water, which is
incompressible, so they are not crushed. Humans could not survive
under that much pressure because air-filled spaces in our bodies,
such as our lungs, would collapse. We need our lungs inflated to be
able to breathe. Some animals that live in the deep ocean do have
gas-filled swim bladders that function well in their high-pressure
environment. Problems can arise if these animals are brought up to
shallower water, where the water pressure is lower.
How could high pressure be beneficial to deep-sea animals?
The extreme pressure of the deep ocean prevents superheated
hydrothermal vent fluid from boiling. Even though the temperature
of vent plumes may reach 390°C (734°F), the water does not boil.
When pressure on a liquid is increased, its boiling point goes up.
The extreme pressures in the deep ocean increase the boiling point
of the water, so that it does not boil at this temperature.
To read about boiling points in the deep ocean, check out the “Dive
and Discover” website by Woods Hole Oceanographic Institution:
http://www.divediscover.whoi.edu/vents/boiling.html
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Education Guide – Grades 5 to 8
Theme 4: Deep-Sea Destinations
Exhibit Description
At this point in the journey, visitors explore some of the deep sea’s
most amazing destinations. While encountering these actual
undersea locations, they can study the creatures that live in these
unique habitats. They can also meet the scientists who explore
these areas, and learn about the research being done.
Deep-Sea Destination: Deep-Sea Canyons
Deep-sea canyons are some of the most extraordinary landscape
features on Earth. They are often found at the edges of the world’s
continental shelves and can be many thousands of feet deep.
Submarine canyons are home to a great variety of marine life, and
visitors learn how life has adapted to the conditions at various
depths.
Marine Protected Areas (MPAs), including some deep-sea
canyons, are being identified and created in the deep ocean. The
Gully on the east coast and the Monterey Canyon on the west coast
are some of the largest North American canyons located within
protected areas. The dramatic cliffs and profiles of these submarine
canyons rival any canyons on land, and create a variety of habitats
for unique animal communities.
Deep-Sea Destination: Abyssal Plains
The abyssal plains are the flattest places on Earth! These vast, flat
areas make up 40% of the world’s ocean floors and cover more
area than all of the Earth’s land surfaces combined. The abyssal
plains are covered with a thick blanket of sediment consisting of
organic and inorganic material that falls from above. Marine life is
not as abundant here as it is in other ocean habitats, as food is very
scarce. Many abyssal plain creatures have developed ways to
conserve energy in their search for nutrition. Visitors will be
surprised as an animatronic lizardfish lunges from near the ocean
bottom as if to devour unsuspecting prey. At the Whale Fall exhibit,
visitors learn that the arrival of a whale carcass is a tremendous
injection of food to this environment, feeding hundreds of species of
animals for decades.
Deep-Sea Destination: Hydrothermal Vents
At various locations throughout the world’s ocean, the Earth’s
tectonic plates are moving apart, and cracks are created in the
seafloor. When cold seawater enters these cracks and circulates
deep in the crust, it becomes extremely hot from the heat of molten
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Education Guide – Grades 5 to 8
material deep below. This superheated fluid rises and spews out
like a geyser, carrying chemicals such as noxious hydrogen sulfide
from within the Earth. Hydrothermal vents may appear to be the last
place to support life, but peculiar life forms colonize them.
Hydrothermal vent ecosystems derive their energy from the
chemicals dissolved in the superheated water. Chemosynthetic
bacteria use the materials released from the vents to produce
nutrients, supporting ecosystems that are almost entirely
independent of the Sun.
At a life-size model of a black smoker vent on the East Pacific Rise,
visitors discover how hot it is at different locations by pushing
buttons to reveal typical temperatures, and learn how all vent
animals ultimately depend on chemosynthetic bacteria for survival.
At the Alvin Theater, visitors embark on virtual dives to explore
three different types of vent animal communities.
Deep-Sea Destination: Seamounts
Seamounts are undersea mountains, usually formed by deep-sea
volcanoes, which rise from the ocean floor as distinct features, but
do not reach the surface. Visitors press a button to reveal a
seamount model hidden below the ocean’s surface, and marvel at
the richness of life around it and in the water column above it.
Currents from the ocean floor swirl around many seamounts,
bringing nutrient-rich waters from the depths. As a result, many fish
and invertebrate species populate seamounts. The upwelling
nutrients can continue to the ocean’s surface, and support an
abundance of marine life above and below the water’s surface. At
the Seamount Lab, visitors examine seamount specimens,
including corals. Little-known, long-lived deep-sea corals are often
found on seamounts, and can provide important habitat, shelter and
spawning areas for certain fish species.
Key Concepts
The deep ocean is composed of the following different types of
habitats:
• Deep-Sea Canyons;
• Abyssal Plains
• Hydrothermal Vents, and
• Seamounts
Deep-Sea Canyons
Deep-sea canyons contain a rich supply of food that supports an
abundance of marine life. Deep oceanic water, rich in nutrients, is
transported up the canyon to the surface. The canyon also
transports organic-rich sediment down into the deep sea.
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Education Guide – Grades 5 to 8
The Monterey Canyon is similar in size to the Grand Canyon. It
extends from the coast of central California, across the continental
shelf, to waters 3,800 meters (12,450 ft) deep. It was the first
known deep-sea canyon when it was discovered in 1857. Today, it
is one of the best-studied canyons in the world.
The Gully is a submarine canyon located east of Nova Scotia,
Canada, at the edge of the continental shelf. It is a large, steepsided canyon with an incredible diversity of habitats and a diversity
of species, including deep cold-water corals and rare northern
bottlenose whales. The Gully, the largest submarine canyon on the
east coast of North America, descends to 2,500 meters (8,200 ft)
depth.
Abyssal Plains
Abyssal plains cover 40% of the ocean’s seafloor at a typical depth
of 4,500 meters (14,800 feet). Most of the creatures are scavengers
that grow slowly, move slowly, reproduce slowly, and live longer
than their shallow-water relatives.
Hydrothermal Vents
Some of the most unique environments in the deep sea are found
at hydrothermal vents, underwater hot springs often located along
mid-ocean ridges. Cold seawater that seeps into cracks in the
seafloor is superheated by molten rock, and scalding mineral-rich
fluid spews back out. As the hot fluid meets cold seawater, minerals
are deposited, sometimes forming tall chimneys. Black smoker
chimneys can reach as high as a 15-storey building or more!
Hydrothermal vents release hot fluid into the cold, deep ocean.
While normal seawater temperatures in the deep ocean are only
2°C to 4°C (36°F to 39°F), the temperature of seawater around a
vent may be 20°C to 40°C (68°F to 104°F), and the temperature of
the fluid in a black smoker plume itself may reach 390°C (734°F).
Despite the extreme heat and noxious vent chemicals,
hydrothermal vent communities support a wide variety and
abundance of unique sea creatures, including tubeworms, “blind”
shrimp, giant clams and vent crabs. These animals are uniquely
adapted to their environment. At least 100 hydrothermal vents have
been explored in the Pacific, Atlantic and Indian basins, and many
more discoveries are yet to come.
Seamounts
Seamounts are sometimes considered “oases of life” in the ocean.
Swirling currents carry nutrient-rich waters from the depths,
supporting an abundance of life. Seamounts also attract a great
diversity of creatures because their elevation creates a variety of
habitats above the often-flat seafloor. As you travel from the base
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Education Guide – Grades 5 to 8
to the summit, life on a seamount increases in abundance – the
opposite of mountains on land.
Activity 5: Create a Vent Animal
Students will learn about a variety of vent animals and how these
animals are specially adapted to live near hydrothermal vents. They
will use this knowledge to invent a new type of animal and describe
its special adaptations to life in the deep sea. This activity can be
conducted individually or in pairs.
Materials
•
•
Access to the Internet and library resources
Pictures of tubeworms
Introduction
Introduce the concept of hydrothermal vents and describe how
hydrothermal vents form.
Ask the students to identify some of the challenges that organisms
would face in a hydrothermal vent community. List the challenges
on the board: no light, high pressure, noxious vent gases, extreme
heat, toxic dissolved metals, acidic vent plumes.
Explain that hundreds of vent animal species have been
discovered. Vent animals have evolved special adaptations that
allow them to thrive in this environment, despite these challenges.
Review the terms adaptation and evolution. Adaptations are
inherited characteristics that allow organisms to live under specific
sets of circumstances. Individuals do not adapt – they inherit their
adaptations. Through the process of natural selection, animals with
adaptations that are most suited to the environment will survive and
reproduce, passing those traits onto the next generation.
Adaptations can include physical features, size, shape, ways of
moving, ways of feeding, means of protecting themselves, and
reproductive strategies.
Discuss tubeworms as an example of a common hydrothermal vent
creature. Pass around a picture of a tubeworm. There are several
types, but giant tubeworms (Riftia sp.) are very large worms that
can grow up to 3 meters (10 feet) long. They live in clusters of
millions of individuals near hydrothermal vents. They do not have
eyes, a mouth, stomach or digestive system. To get their nutrition,
tubeworms have a symbiotic relationship with a special kind of
bacteria, called chemosynthetic bacteria.
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Education Guide – Grades 5 to 8
A symbiotic relationship means that two organisms live together,
each helping the other to survive. The tubeworms deliver chemicals
from vent fluid and seawater to the bacteria that live inside their
tubes; in turn, the bacteria provide nutrition to their worm hosts. If
tubeworms did not have this “partnership” with the bacteria, they
would not be able to live. Similarly, if the bacteria did not have the
tubeworms, the bacteria would not survive.
Tubeworms have long, red plumes (like gills) that are full of
hemoglobin, the same material that makes our blood red. The
hemoglobin in the blood of the plumes absorbs hydrogen sulfide
from vent fluid and oxygen from seawater, and transports these to
the bacteria that live in a structure of the tubeworm called a
trophosome. The bacteria convert these chemicals and carbon
dioxide into sugars that provide nutrition for the tubeworm.
Tubeworms live in tubes made of chitin, the same material in
exoskeletons of crabs and shrimp. The tubes protect the worms
from predators and shield them from the noxious vent chemicals. A
worm can never leave its tube, but it can pull its plume inside if a
hungry crab comes along.
Make a list on the board of all the adaptations of tubeworms that
make them suited to their environment.
For reference, two illustrations are provided below. One shows the
internal structure of a giant tubeworm, and the other provides an
overview of hydrothermal vents and the life forms that inhabit them.
See Appendix 3,
file “COTA
Theme 4_
Tubeworm
Diagram” for
larger version of
this diagram.
Diagram
reproduced from
http://noaa.gov
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Education Guide – Grades 5 to 8
See Appendix 3, file “COTA Theme 4_Hydrothermal Vent” for
larger version of this diagram at higher resolution.
Activity
Teacher Preparation:
1. Arrange for students to have access to the Internet and library
resources. Suggested sites include:
http://www.divediscover.whoi.edu/vents/biology.html;
http://www.ceoe.udel.edu/extreme2001/creatures/;
http://www.noc.soton.ac.uk/chess/education/edu_htv.php
Also refer to the list of resources in Appendix 2.
Procedure:
1. Each student or pair of students should select one vent animal
species from the list below.
2. Using the Internet or library resources, find out as much as you
can about that animal. Download or print out a picture of the
animal and answer the following questions:
o What does the animal feed on or how does it obtain its
nutrition?
o How does the animal protect itself?
o How does it move?
o How large is it?
o In what ways is this creature uniquely adapted to live in
this environment? (physical features or behavior)
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Education Guide – Grades 5 to 8
3. Project digital images or pass around the printed pictures of the
vent animals that were researched. As each image is displayed,
the pair who researched that species should describe the
adaptations of the species.
4. Each student/pair should use the knowledge they gained from
their research to invent a new vent species. Draw a picture of
the animal, give it a name, and describe the following:
o Its main body parts and functions
o How the animal obtains its nutrition
o How the animal moves
o How it protects itself
o Any other unique features
5. Each student/pair should present and describe their invented
animal to the class.
Species that inhabit hydrothermal vents:
• Giant tubeworm (Riftia pachyptila)
• Giant clam (Calyptogena magnifica)
• Vent crabs (Bythograea sp., Cyanograea sp., Segonzacia
mesatlantica)
• Vent eelpout/zoarcid fish (Thermarces Cerberus)
• Vent octopus (Vulcanoctopus hydrothermalis)
• Pompeii worms (Alvinella pompejana)
• Squat lobster (Munidopsis alvisca)
• Spider crab (Macroregonia macrochira)
• Vent limpet (Eulepetopsis sp., Lepetodrilus sp.)
• Mussels (Bathymodiolus sp.)
• Brittle stars (Ophiactus sp.)
Discussion
Which invented species were the most unique?
What are some of the most common adaptations of vent
animals?
Symbiotic relationships with chemosynthetic bacteria are common.
Animals at hydrothermal vents ultimately rely on chemosynthetic
bacteria for their survival, because the bacteria form the basis of
the food chain. Some animals have chemosynthetic bacteria in their
tissues, providing them with a built-in food supply in a symbiotic
relationship. Other animals feed directly on the bacteria. Some
animals are scavengers and predators of other vent animals.
Why would there be more animals living around hydrothermal
vents than in other regions of the deep ocean?
The fluid released at hydrothermal vents is rich in chemicals from
within the Earth. Chemosynthetic bacteria use the chemicals from
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Education Guide – Grades 5 to 8
vent fluids and seawater to produce energy and food, supporting
ecosystems that thrive in the absence of sunlight.
References
This activity was adapted from:
NOAA Ocean Explorer, Section 7 Individual Species in the Deep
Sea. “Invent a Deep-Sea Invertebrate”
http://oceanexplorer.noaa.gov
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Education Guide – Grades 5 to 8
Theme 5: Deep Ocean Habitat
Exhibit Description
An interactive digital projection globe, videos and graphics allow
visitors to explore ocean topics such as the ocean’s ecosystems,
current challenges and threats, and how human activities are
impacting the ocean. Before “returning to the surface”, visitors are
encouraged to leave their own messages about the ocean and their
experience in the abyss.
Key Concepts
Some human activities are detrimental to the ocean.
The Earth has one large ocean with many different names. All of
the ecosystems within the ocean are interconnected. Human
activities affect all parts of the ocean, not just any small area.
Some of the largest threats to the health of the ocean include:
• Ocean acidification
• Overfishing
• Deep-sea mining
• Non-point source pollution, including plastic litter
Overfishing
Unsustainable harvesting of marine species for human
consumption can have devastating consequences on the food
webs of the entire ocean, even affecting creatures in the very deep
ocean. The energy of the deep ocean comes from surface and
coastal areas. Dead plants and animals from the surface fall to the
bottom and become food for animals in the deep sea (for example,
marine snow and whale falls). As more creatures are removed or
fished from surface and coastal zones, there is less food available
for creatures in the deep ocean. Remember that all of the “oceans”
are connected into one ocean, and that a continuous column of
water connects all of the water from the surface down to the
seafloor.
Ocean acidification
The ocean absorbs about one third of the carbon dioxide (CO2) that
we emit into the atmosphere. Dissolved CO2 makes the seawater
more acidic, and damages the hard parts of marine creatures such
as mussels, corals, and many of the small animals that form the
base of marine food webs. Further, as global warming continues, a
warmer ocean will become less effective at absorbing CO2 from the
atmosphere, and as more CO2 collects in the atmosphere, global
warming will continue. This is a positive feedback loop, and it
affects every living creature on our planet. Scientists are currently
conducting research to determine how the chemistry of the ocean
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Education Guide – Grades 5 to 8
will change and how these changes may affect individual
organisms and deep-sea food webs.
Deep-sea mining
Hydrothermal vent areas of the ocean floor are rich in mineral
deposits. Deep-sea mining of those deposits is poised to begin
now. However, the mining methods are potentially destructive, and
scientists do not understand these deep-sea ecosystems enough to
know how deep-sea mining may impact them.
Non-point source pollution
Everything we put on the ground, such as garbage and chemicals,
goes into storm drains and into rivers and lakes and eventually
ends up in the ocean. This is called non-point source pollution.
Plastics are especially detrimental because they do not completely
degrade in the ocean. A piece of plastic put into the ocean today
may be there forever, may break down into very small pieces, or
may break down into chemicals that pollute our water. Sea
organisms can mistake these plastic items for food or become
entangled in them, resulting in death.
Activity 6: Ocean Acidification Eggshell
Experiment
Students will learn how ocean acidification occurs and discover
how an acidified ocean could be detrimental to marine animals,
including those that live in the deep sea. They will perform two
experiments to discover how CO2 lowers the pH of water and to
observe the effect of an acidic solution on eggshells and seashells.
This is a group activity.
Materials for Part 1
• Water
• Beaker or clear plastic cup
• Straw
• Universal indicator
Materials for Part 2
• Two large jars with lids
• Eggs (uncooked, shells on)
• Vinegar (weak acetic acid)
• Water
• Sea shells of various types (chalk can also be used)
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Education Guide – Grades 5 to 8
Introduction
Ask the students to think of ways that the health of the ocean is
being threatened by people’s actions. Some examples may include
oil spills, large-scale and small-scale pollution, overfishing and
plastic litter. Briefly discuss the students’ examples and how
humans can have an impact on the health of the ocean and its
inhabitants.
Some impacts, such as oil spills, may affect mostly animals that live
near the surface. Others, like overfishing and ocean acidification,
can affect animals that live throughout the ocean’s water column,
including creatures in the deep ocean.
Explain ocean acidification. The ocean absorbs one third of the
carbon dioxide (CO2) that humans emit into the atmosphere. The
dissolved CO2 changes the chemistry of the ocean and makes the
seawater more acidic. Many plants and animals in the ocean have
shells that are made out of calcium carbonate (CaCO3). The acid
resulting from the carbon dioxide actually etches away and
damages the hard calcium carbonate shells. Some of these
animals are larger creatures such as mussels or corals, but many
of the small animals that form the base of marine food webs like
plankton will be and are being affected.
Pristine seawater has a pH of 8.0 to 8.3. Review the pH scale and
emphasize the fact that it is a logarithmic scale, so a change of 1
pH unit is actually a 10-fold change. Even a small reduction in the
pH of the ocean can have significant effects on marine organisms.
Since industrialization, there has already been a surface seawater
reduction of 0.1 pH units.
Activity
Preparation:
1. Ask students to gather seashells (from a coastal area or from
consumed seafood).
Note: If you have no access to seashells, you can try
substituting with regular chalkboard chalk.
Procedure for Part 1:
1. Pour approximately 50 milliliters (1.5 oz) of tap water into a clear
plastic cup or beaker.
2. Add 10-20 drops of universal indicator and mix with a straw.
Record the color of the solution and compare it to the color chart
to determine the approximate pH of the tap water.
3. Slowly exhale through the straw into the water. Take a breath
and slowly exhale some more. Continue until you observe a
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Education Guide – Grades 5 to 8
color change. Record your observations about the color of the
solution and compare to the color chart to determine the
approximate pH reading at the conclusion of the experiment.
Procedure for Part 2:
1. Place one egg in each of two containers.
2. Sort shells into matching pairs of the same type and
approximate size. Note: If the shells are dirty, clean them first
with a soft scrub brush and water.
3. Place one of each shell pair into each of the two jars, so that
each jar contains the same types of shells.
4. Measure and record the pH of vinegar and tap water.
5. Fill one of the jars with tap water and the other jar with vinegar.
The egg and seashells should be fully immersed in the liquid.
Seal the jars with lids.
6. Record initial observations for both containers (bubbles may
form in the vinegar container as the eggshell begins to break
down).
7. The next day, open the jars, remove the eggs and place them in
a dish. Record observations for each (appearance, thickness,
strength or softness). Record the pH of the vinegar solution and
water solution. If there is not much difference between the two
eggs after a day, replace the eggs in the containers and wait
another day.
8. When you are finished making observations with the eggs,
remove them from the jars. Leave the seashells in the
containers for several more days, checking daily to see if there
is any breakdown of the shells in the vinegar container and
measuring the pH of the vinegar solution.
9. Optional: measure the change in mass of the dried seashells
before and after the experiment.
Discussion
Part 1:
Why wasn’t the tap water exactly pH 7.0 at the beginning of the
experiment?
Pure, distilled water is 7.0, but tap water often contains dissolved
minerals that increase or decrease the pH slightly from neutral.
What happened to the color of the solution when CO2 was
added? What does this color change mean?
The color of the solution should change as the student exhales CO2
through the straw. The pH of the solution should decrease
indicating that the acidity of the solution is increasing.
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Education Guide – Grades 5 to 8
Part 2:
Why do bubbles form when the egg is placed in the vinegar?
As the calcium carbonate breaks down, carbon dioxide gas is
released.
What happened to the eggshell in the vinegar container? Why?
The eggshell became softer and started to break down. The acidic
solution caused the calcium carbonate in the eggshell to dissolve.
What happened to the pH of the vinegar solution? Why?
The pH increased and the solution became less acidic because the
calcium carbonate from the eggshell is basic.
What happened to the seashells in the vinegar solution? Why?
The shells will begin to dissolve as well. Thinner shells may break
down faster than thicker shells. The seashells also contain calcium
carbonate.
How can ocean acidification be detrimental to marine
organisms?
Organisms with a shell, supporting structures or exoskeleton made
of calcium carbonate (such as bivalves, crustaceans, corals) will
not be able to survive if the acidity increases to the point where
their shells begin to break down.
References
This activity was adapted from:
Monterey Bay Research Institute Earth Lesson Plans, Ocean
Acidification: “pH, CO2 and Ocean Acidification”
http://mbari.org/earth/
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Education Guide – Grades 5 to 8
Play Dough Recipe
Stir the dry ingredients together in a saucepan:
• 1 cup flour
• ¼ cup salt
• 2 tablespoons cream of tartar
Add the following:
• 1 cup water
• 2 teaspoons food coloring
• 1 tablespoon cooking oil
Cook and stir over low/medium heat for 3 to 5 minutes, or until it
sticks together in a ball. Remove from saucepan and knead for a
few minutes on a lightly floured surface. Store in an airtight
container.
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Education Guide – Grades 5 to 8