The discovery that the Mystery Fossil was pregnant tells us that the Mystery Fossil came from a species that gave live birth. What do you know about how whales, wolves, or crocodiles carry their babies?

Paleontologists look for shared body structures in different species. There are many different body structures and some of them can be difficult to find. Which of the body structures in the list can you find in each of the species below?

Cross out the structures that the Mystery Fossil does not have, leaving only the present traits:

Cross out the structures that the Whale does not have, leaving only the present traits:

Cross out the structures that the Wolf does not have, leaving only the present traits:

Which bone structures are similar between the Mystery Fossil, whale, and wolf?

CFS:

• student describes the relationship between anatomical similarities and differences in animal species

• student describes the chronological difference between animal species with a common ancestor based on body structures

Based on your answer to Question 5, do you think the whales, wolves, and the Mystery Fossil are related?

CFS:

• student describes the relationship between anatomical similarities and differences in animal species

• student describes the chronological difference between animal species with a common ancestor based on body structures

Identify the ‘descendant’s and the ‘common ancestor population’ shown below.

. CFS:

• student describes the relationship between anatomical similarities and differences in animal species

• student describes the chronological difference between animal species with a common ancestor based on body structures

How can you use structural evidence to help support why Species B and Species C are related species?

CFS:

• student describes the relationship between anatomical similarities and differences in animal species

• student describes the chronological difference between animal species with a common ancestor