Getting StartedIntroductionWhat Did T. rex Taste Like? is an introduction to cladistics, the most commonly used method of classification today.Cladistics organizes living things by common ancestry and evolutionary relationships, enabling us to betterunderstand life's present diversity and evolutionary history.

Like other methods of classification, cladistics makes use of the observable features of organisms. Cladistics alsoallows us to examine the ways in which features change within groups, and to observe patterns of origin anddiversification over time. Unlike any other method of classification, cladistics is a powerful predictive tool, allowingus to propose hypotheses about the relationships between organisms.

This module presents a simplified version of the process used to generate cladistic analyses and demonstrates itspredictive power. Typically dozens or even hundreds of features are examined before a cladogram is produced.Although in this module only structural features are used, true cladistic analyses also use biochemical, genetic andeven behavioral features.

Time RequirementsTeacher Preparation: 45-60 minutes to review the Teacher's Guide and TourTour: 3-4 class periods (dependent on student learning and reading levels)

Grade Level7-12

This recommendation is dependent on student learning and reading levels. This module contains a moderate amountof detail and some new vocabulary.

Preparation

Name PeriodDateScience

What Did T. rex Taste Like?An introduction to how life is related

Log onto:http://www.ucmp.berkeley.edu/education/explorations/tours/Trex/navigation.htmlFollow the instructions and complete the handouts as you go. If you see a hypertext word which youwould like to see defined you can either click on the word or look at the Terms List below.

Page 1 of 4

Terms ListAmniotic egg: an egg that can be laid on land due to the presence of a fluid-filled amniotic

sac that cushions and protects the developing embryoBipedal: describing an animal that typically walks on two legs.Bony skeleton: a skeleton formed from hardened bone, not cartilage.Common ancestor: an ancestor shared by two or more lineages.Genealogy: a family history.Hypothesis: a statement suggesting an explanation for an observation.Lineage: any continuous line of descent;those organisms connected by heredity from

ancestor to descendent.Most recent common ancestor: the most recently shared ancestor of two or more

lineages.Quadrupedal: describing an animal that typically walks on four legs.Tetrapod: an animal having four limbs for terrestrial locomotion.Vertebrate: an animal having a back bone or spinal column.

What did Trex Taste Like.cwkkew 04/02

Name

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Add

ition

al D

ata

Name

Special Assignment: Solving T. rex's Identity CrisisPurpose:Use direct and indirect evidence to make inferences about T. rex .Materials needed: * Cladogram with additional data * Your Data Table

Que

stion

Is th

ere e

noug

h da

ta to

mak

e a

hypo

thes

is?

My

hypo

thes

is is:

The j

ustif

icat

ion

for m

y hy

poth

esis

is ba

sed

on th

e ob

serv

ation

that:

In o

rder

to su

ppor

t or

refu

te m

y hy

poth

esis,

I w

ould

nee

d da

ta ab

out:

Did

T. r

ex

have

an

amni

otic

egg?

Was

T. r

ex

war

m-b

lood

ed

or co

ld-

bloo

ded?

Coul

d T.

rex

have

had

fe

athe

rs?

Did

T. r

ex

have

colo

r vi

sion?

How

man

y ch

ambe

rs w

ere

ther

e in

T.

rex's

hea

rt?

Did

T. r

ex

sing

to it

s of

fspr

ing?

Wha

t did

T.

rex

taste

like?

Name

Post-TestWhat Did T. rex Taste Like?Directions: Please answer each of the following questions.

1. What is a cladogram?

2. Draw a cladogram with a frog, cow, and horse correctly placed.

3. Please circle the answer that best completes this statement: A "common ancestor" is:a . one that is very commonly seen in the fossil record.b . one that is shared by two or more organisms.c . one that has no distinguishing features and is therefore very "common."

4. Read the following statements then answer the question below.A. All organisms inherit features from their ancestors.B. Organisms resemble their most recent ancestors more closely than distant ancestors.C. Over time evolution occurs and features change.

Which of these statements are accurate?a . A and C.b . B and C.c . All of the above.d . None of the above.

5. Examine the following diagram. Which of the following statements are correct? (Circle all correct statements)

a . Crocodiles are more closely related to frippities than to squirrels.b . Frippities share a more recent ancestor with Triceratops than with Pigeons.c . Frippities probably laid eggs.d . All of these animals share the same ancestor.

http://www.ucmp.berkeley.edu/education/explorations/tours/Trex/guide/posttest.html

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