Evidence for Evolution Exploration

Name: _____________________________________________________ Date: ________ Period: _____ Evidence for Evolution Exploration D Much evidence has been found to indicate that living things have evolved or changed gradually during their natural history. The study of fossils as well as work in embryology, biochemistry, and comparative anatomy provides evidence for evolution. Part 1: Homologous Structures: 1. Homologous Structures are __________ inherited by two different organisms from a _______________ ____________ that have the same ______________, but have adapted different __________________. 2. With your partner, complete the table below using the “Evidence for Evolution Exploration” PowerPoint posted for your class. Mammal Bat Function (What is the forelimb used for?) (How are the bones arranged as compared to the other mammals?) Structure (How is the forelimb structure adapted to its function?) Flight Fingers parallel at the end of arm bones; extra finger! Straight down from shoulder; phalanges parallel to each other Mole Wolf Human Arrangement Thick and large structure Hunting and gathering Elephant Stacked on top of each other to support weight Thick bones Sea Lion Long, paddle-like phalanges Powerfully structured forelimb Opossum Average size bones 3. How do homologous structures provide evidence of a common ancestry? 4. Why are the bone structures different between each animal? 5. Which mammal in the chart above probably represents the most similar structure to the common ancestor that all others are likely evolved from? (hint: Which mammal has the most general form compared to the others?) Part 2: Analogous Structures: 6. Analogous structures are the various structures in ______________________ species having the ___________ function, but that evolved _________________ and do ____________ share a ________________ ________________. 7. Look at the 2 arm/wing slides. What is it about these similar structures and the organisms they are found on that makes them Analogous? 8. Observe the wing slide; what is the function for each of the wings pictured? 9. How are these structures different? 10. Do birds and insects share any structural (inside the wing) similarities that would suggest they are closely related taxonomically? 11. Watch the video and compare Homologous vs Analogous: Homologous Part 3: Vestigial Structures: Analogous 12. Vestigial structures are often _____________________________to structures that are functioning normally in other species but serve no current _________________ in some species. Therefore, vestigial structures can be considered evidence for evolution, the process by which beneficial heritable traits arise in populations over an extended period of time. 13. Watch the vestigial video clip and review the pictures of various vestigial structures. 14. List a few vestigial structures in man and in other organisms. 15. Observe the Cavefish and Minnow slide. 16. The cavefish and minnow are related, but the cavefish is blind. Why is eyesight not an important adaptation to life in a cave? 17. What do you think has become the most important adaptation of the cavefish (think about senses)? Explain. 18. Read the list of human vestigial structures. Complete the chart below: Structure Possible Function Why Vestigial? Appendix (digests leaves in Digest fibrous plant material koala bears) Coccyx (tail bones) Support for tail bones Muscles that move ears (work in dogs) Humans do not need to move their ears to hear predators Muscles that make hair stand up Our hair is not long enough to make us puff out and look bigger Little toe Used by primates to cling and swing Wisdom teeth Chew coarse and rough foods such as nuts, roots and raw meats Part 4: Homologous or Not Game: Play the game on the last several slides of the PowerPoint. List your answers below: 1. 2. 3. 4. 5. ____________________________________ ____________________________________ ____________________________________ ____________________________________ ____________________________________ 6. ___________________________________ 7. ___________________________________ 8. ___________________________________ 9. ___________________________________ 10.___________________________________ Part 5: Conclusion: What are some of the pieces of evidence that support evolution? Explain the evolutionary relationship between the fin of a fish and the flipper of a whale.