1. What are the 2 pieces of evidence for evolution we have discussed so far? Initiation:

2. The Evidence for Evolution Nothing in biology makes sense except in the light of evolution. -- Theodosius Dobzhansky Key Question What evidence supports the theory of evolution?

3. Content Objectives 1. Identify evidence Darwin used to present his case for evolution.

4. Key Points 1. Homologous structures are one type of evidence for the evolution of living things. 2. Early stages, or embryos, of many animals with back bones are very similar.

5. Major Vocab Homologous Structures - Structures that have different forms but develop from the same embryonic tissue. Vestigial Organs - Organ that serves no useful function in an organism. Embryo - organism in its early stages of development.

6. Homologous Body Structure 1. Scientists have noticed that animals’ body part structure have striking similarities. 2. Homologous structures provide strong evidence that all 4-limbed vertebrates have descended, with modifications, from common ancestors. What are some examples of 4-limbed vertebrates?

7. What similarities do you see between these 4 animal parts? Example 1-Animal Limbs Even though these structures serve very different functions, their origin is from the same embryonic tissue.

8. Example 2 -Vestigial Organs Humans have several vestigial organs! The Appendix The Tailbone

9. Similarities in Embryology 1. Many embryos look especially similar during early stages of development. 2. The same group of embryonic cells develop in similar patterns.

10. Example Match the embryo with the proper organism! DogHumanMouseTurtle ADCB

11. The Leopard Frog

12. FROG DISSECTION!!! You do not have to touch, but you do have to participate. No unnecessary cuts. If you have a question, ask! Respect the animal that we are learning from. Have fun!!!

13. Preview of what you will see...

14. Write a summary of what you just learned. Termination: