Download Lab 6: Animal Diversity

Bio 10
Lab 6: Animal Diversity
Most people, when they think of animals, think
of those similar to ourselves: dogs, cats,
horses, apes, tigers and other mammals.
However, the Kingdom Animalia is in fact a
very diverse one, with mammals being just a
minor group in terms of numbers of species.
Actually, in terms of diversity and numbers, the
Arthropods are far and away the most
dominant and arguably the most important
group ecologically.
In today’s lab we will be exploring the characteristics and significant adaptations
of the various animal phyla. We will look at the basic morphological features of
each phyla and note increasing levels of complexity, the appearance of new
features or adaptations, and characteristics that are unique to each group.
Taxonomy: the science of naming things.
Members of the animal kingdom are placed in increasingly more exclusive
categories using the taxonomic scheme:
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Kingdom, phylum, class, order, family, genus, species
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King Phillip Came Over For Green Spaghetti
A species is defined as a group of organisms that have similar anatomical
characteristics and are able to interbreed.
Organisms are given two names, the genus and species names. For example
human beings are called Homo sapiens. This is called binomial nomenclature.
Bio 10
Opposable Thumb Activity
The opposable thumb is a distinctly primate trait. Humans, as well as monkeys,
gorillas, and other primates, have a hand that can grasp objects, a very useful
adaptation as you will see.
In this lab, you will perform several common actions. Then you will change your
hand so that it resembles that of a non-primate animal. You will determine
whether or not you can successfully perform the same actions.
Procedure:
• Choose 3 of the following tasks. Perform each task and time how long it
takes with your thumb free.
• Have your partner help you tape your thumbs to the palms of your hands.
• Perform each task again and time how long it takes. If the activity takes
longer than 5 minutes, record the word “unsuccessful”.
• Answer the questions on the Lab Group results sheet.
Tasks:
• remove one shoe
• put on your shoe again, and tie the lace
• unbutton two buttons
• button two buttons
• write your name
• write the numbers 1 through 10
• find page 55 of a text book
Data:
Task
Thumbs free (time)
Thumbs taped (time)
Bio 10
Owl Pellet Analysis
We will be looking at owl pellets produced by Barn Owls (Tyto alba). The pellets are
masses of undigested food that are regurgitated by birds of prey. Don’t worry! They are
sterilized!! The pellets contain the bony portions of prey, as well as any fur, feathers,
scales, beaks, teeth, claws, and/or insect exoskeletons that may have been consumed.
These materials are hard to digest and of little nutritional value.
The pellets can be used to determine the dietary habits off the raptor (meat-eating birds
of prey) being studied, as well as to determine the prey that is available in the raptor’s
habitat.
PART I: Dissecting Owl Pellets
Working in pairs, take one owl pellet to your lab table. To dissect the pellet, begin
loosening the hair and/or feathers using a dissecting needle. As bones are uncovered,
carefully remove them and place them to the side. After you have removed all skulls
and bones, you can begin to identify the prey.
NOTE: If you find that the pellets do not come apart easily you can soften them by
soaking them briefly in warm water.
PART II: Using a Dichotomous Key
Dichotomy is defined as the process of dividing into two mutually exclusive or
contradictory groups.; To use a dichotomous key, simply compare the first pair of
statements and determine which one best fits the article you are trying to identify. After
you pick one of the paired statements, you will be directed to other paired statements
until you reach an answer. For example, assume that you want to identify a common
U.S. coin using a dichotomous key. The key might read:
1.
Coin edge smooth……………………………………………..go to 2
Coin edge grooved…………………………………………….go to 3
2. Coin copper in color……………………………………………Penny
Coin silver in color……………………………………………….Nickel
3. Picture of Roosevelt on front………………………………….Dime
Picture of Washington on front……………………………….Quarter
Dichotomous Key
Use the DIchotomous Key and Skull Characteristics chart to identify the skulls of small
mammals found in your pellets and record the number of each type on the
accompanying worksheet labeled “Pellet Contents”. Disregard insects that may be
found.
Bio 10
Selected Animal Phyla
Phylum Name
Description
Porifera
Sponges
No tissues, organs, nervous system, appendages
Most asymmetrical (a few radial)
Have internal skeleton of CaC03 or silica
Filter feeders by circulating water through pores
Cnidaria
Jellyfish, anemones, Hydra, corals
Radial symmetry
Two body plans: polyp and medusa
• Polyp: sessile (stalked as Hydra, anemones)
• Medusa body plan (jellyfish)
Loose tissue layers
Stinging cells for offense/defense (some stings are lethal to
humans), Cnidaria = nettle
Platyhelminthes
Corals make reefs of CaC03 which they secrete around their soft
bodies: very, very important ecologically and economically.
Flatworms, flukes, tapeworms
Nematoda
Many parasitic, some free-living (usually aquatic)
Primitive nervous system (except tapeworm)
Incomplete digestive system (what goes in comes out of same
opening)
1st to show bilateral symmetry with cephalization (head formation)
Un-segmented round worms
Both parasitic and free living
No true body segmentation
Bilateral symmetry
Complete digestive tract (mouth to anus)
Primitive nervous system
Trichinella (parasite of us, pigs), Ascaris (intestinal round worm),
Tubatrix (the vinegar eel), Soil nematodes such as Caenorhabditis
elegans (genetics studies)
Mollusca
Clams, snails, mussels, slugs, abalone, squid, octopus etc
Body enclosed in a thin mantle that secretes a shell of one, two or
eight parts. (ie: snail=1, clam=2, chiton=8)
Have ventral muscular foot modified for crawling (as a snail),
burrowing (as a clam), or swimming (as a squid).
Mollusca = stomach foot
Complete digestive tract, nervous system with nerve ganglia,
capable of fine, directed movement
Most with a radula (feeding structure with rows of teeth) Used
either for scraping up food (snail) or grasping prey (squid)
Most free living (not parasitic), most marine
Bio 10
Description
Phylum
Annelida
Arthropoda
Segmented worms: earthworms, leeches, marine worms
Segmented bodies composed of many similar and ring-like
segments, Annelida= little ring
This segmentation is visible externally and internally
Move by use of fluid filled hydrostatic skeleton
Bilateral symmetry
Complete digestive tract, closed circulatory system (blood flows
thru discrete vessels)
Most free living: earthworms, marine worms
Some ectoparasitic: leeches
85% of animal kingdom
Contains >1 million species
Biggest, most diverse and most important phylum
Body usually segmented
Exoskeleton made of chitin (hard, impermeable covering), bilateral
symmetry, complete digestive tract, elaborately jointed
appendages
3 major classes
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Crustacea: crabs, shrimps, lobsters, crayfish, barnacles;
10+ appendages, most marine
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Arachnida: spiders, scorpions, ticks, mites, body in 2 major
segments, 8 legs, wingless
Insecta: grasshoppers, flies, moths, butterflies, beetles,
bees, lice, etc. Most abundant, diverse & widespread of all
animals, body in 3 major segments (head, thorax,
abdomen), 6 legs, most winged as adults
Sea stars, urchins, sand dollars, brittle stars, sea cucumbers
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Echinodermata
Radial symmetry as adults, larvae are bilateral
No head, brain segmentation, skin with tiny projections
Show some chordate characteristics embryologically
Bio 10
Phylum
Chordata
Description
Fish, amphibians, reptiles, birds, mammals
At some point in their life cycles, all chordates have a dorsal nerve
cord running down the back, a notochord (supporting rod made of
cartilage lying just beneath the nerve cord), and pharyngeal gill slits
Subphylum:
Vertebrata
Backbone or vertebral column
INCLUDES THE FOLLOWING CLASSES:
Chondrichthyes: sharks and rays.
Fish w/ cartilaginous skeletons, not bone
Osteichthyes: trout, salmon, goldish,
Have a bony skeleton, gills covered by operculum
Amphibia: frogs, toads, nets, salamanders
Have dual life: adults usually terrestrial, larvae are aquatic with gills,
most thin skinned, eggs without shells
First vertebrates to live out of water
New features for life on land include legs, lungs (not in all), nostrils
Ectothermic (body temp varies according to outside, environmental
temp)
Reptilia: lizards, snakes, turtles, tortoises, crocs and alligators,
dinosaurs
1st vertebrates completely adapted to terrestrial living
Shelled, amniotic eggs (no need to lay eggs in water)
Thick, scaly skin retards water loss
Limbs capable of rapid locomotion (lacking in snakes)
Ectothermic with behavioral temperature regulation
Internal fertilization (why important for land dwellers?)
Aves: birds
Feathers (same derivation as reptile scales)
Endothermic (constant body temp maintained at high cost)
Front limbs modified for flight (wings) in most
Skeleton with hollow, air-filled bones (reduces weight)
No teeth (have lighter beaks)
Very efficient lung/air sac system – useful for energy costs of flight
Internal fertilization, lay eggs
Mammalia: rodents, bats, cats, dogs, horses, cattle, pigs
Mammary glands on females provide milk
Have fur/hair (even on whales)
Usually show high parental investment
Endothermic with generally stable body temp, except in hibernators
Bio 10
Lab 6: Group Lab Report
Names: ___________________________
___________________________
Opposable thumb activity
1.
Which task took the most time with your thumbs taped?
2.
What is the advantage of an opposable thumb?
3.
Humans use their opposable thumbs to operate tools and do other tasks.
Give three specific examples of ways in which this adaptation (the
opposable thumb) would aid in the survival of non-human primates in a
natural environment.
Owl pellet dissection – Constructing a Food Web
Using the data collected from your owl pellet dissection, draw a food web below
with the barn owl at the highest trophic level and grass and seeds at the lowest
level. The intermediate organisms that you show should include every prey type
found by the class.
Bio 10
Animal Phyla. Visit the side counters and look at the specimens on display.
Using the information in the Animal Phyla chart and what you have seen, answer
the following questions.
1.
Which group is the first to show cephalization? What is cephalization?
2.
Which group is the first to have a complete digestive tract?
3.
Which group moves using tube feet? What type of symmetry does this
group have?
4.
Which group is characterized by a muscular foot and a rasping tongue?
5.
In which group do members alternate between sessile polyp forms and free
floating medusa forms?
6.
Which group is the first to possess a closed circulatory system? What is the
advantage of a closed circulatory system?
7.
Which group is characterized by a hard exoskeleton and a body divided into
several large segments?
8.
Which phylum do the following animals belong to? Circle the names of the
animals that are invertebrates.
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black widow spider
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Siberian tiger
Bio 10
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tape worm
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Barn owl
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sea urchin
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sponge
Subphylum Vertebrata
1.
What is the defining feature of a vertebrate?
2.
What are the 5 vertebrate classes? Give examples of the members of each
class.
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3.
Which vertebrate class was the first to become (at least partly) terrestrial?
4.
What adaptations are needed to move onto and survive on land?
5.
Which vertebrate class was the first to become fully terrestrial? Describe
the adaptations in this group (skin, respiratory system, eggs).