Comparison of Human and Frog Skeletons

Themes: Comparative Anatomy - Skeletal Structure and Function

Visit the bones hut on Frog Island. Explore the model of a frog skeleton on the ranger's table. Familiarize yourself with the names of the different bones of the frog. Look at diagrams of a human skeleton and a frog skeleton, as well as other resources on Frog Island and elsewere to answer the following questions.

1. Compare the size of the frog's mouth (in proportion to the rest of its body) and the human's mouth. Why do you think this difference exists?

2. The cranium is the part of the skull that surrounds and protects the brain. Compare the size of the cranium in the frog and in the human. Why do you think this is different?

3. In frogs, the forament magnum (the hole in the skull that the spinal cord passes through) is located in the back of the skull. Where do you think it is in humans and why?

4. Humans have ribs while frogs do not. What could be a reason for this difference?

5. Compare the human and frog spinal columns. How are they different, how are they the same?

6. Look at the bones of the upper arm and forearm. How are they different, how are they the same?

7. Describe the structure of the frog's front feet. Is it similar to or different from a human's?

8. What bone do humans have in the leg (not including the bones of the feet) that frogs do not?

9. Thinking about how they use them, why do you think the shape of a frog's foot and legs is different from a human's?

10. Name some joints that are the same in both frogs and humans.

11. Imagine you were an alien scientist in the future who was exploring the Earth after some catastrophe wiped out all life. If you were looking at the skeletons of a human, frog, and fish, and the shell of a lobster, which would you think are most closely related and which are most distantly related and why?