Family Histories

Activity 98

Challenge: What can you learn about evolution by comparing the fossil records of fish, mammals, and reptiles?

Key Vocabulary:Fossil Record the name given to all the different fossils that have been found anywhere on Earth.

Activity 98: Family Histories

Read the Introduction on Page F-43!

• What is a family, scientifically speaking?

• In science, a family is a level of biological classification.

• We have already studied Kingdom, phylum, class, genus and species

• A Family is a fairly broad classification category that contains many different types of animals

Getting Started…

In the next few activities, we will return to studying fossil evidence.

One part of studying evolutionary history is to look for larger patterns in the fossil record, and that is what we will do today.

1. Glue in Student Sheet 98.1

2. Follow the procedure as it begins on Page F-44-45

3. When you are done Please answer Analysis Questions 1, 2 and 5 in your notebooks with your group.

Procedure:

Corr

ect

Bar

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Analysis #1a. Fish appeared first in the early Paleozoic,

then reptiles in the late Paleozoic, and then Mammals in the Mesozoic

b. The order suggests that fish evolved first, then reptiles and finally mammals.

Maybe speciation occurred eventually leading to the appearance of new classes of vertebrates.

a. A fossil family may disappear in the fossil record because:• Gone extinct• Fossils not created• Fossils not found yet

b. Darwin might say the population didn’t have enough variation to survive change.

Analysis #2

a. During the Cenozoic, there is a huge increase in the diversity of mammals. (There are more mammal fossils found in the Cenozoic than in the Mesozoic)

b. The Mesozoic is often called the “AGE OF REPTILES.” Reptiles display the largest increase in numbers of fossils during that era.

Analysis #5

c. Both speciation and extinction occur at the same time. The Mesozoic may be the first era where reptiles became a common life form, BUT many other types of species were also common during that time, and all others were also undergoing evolutionary changes.