EVOLUTION

1. EVOLUTION EVIDENCE AND THEORY CHAPTER 15

2. 1. What is evolution? • An orderly succession of changes.

3. 2. What is biological evolution? • The change in populations of organisms over generations.

4. Jean Baptiste Lemark(1744-1829) • A encyclopedia author. • Developed the word invertebrate. • Was the first to propose a unifying hypothesis of species modification

5. 4. Explain an acquired trait. • Is a trait that is not determined by genes. • It arises during an organism’s lifetime as a result of the experiences or behaviors. • Ex. He believed that the webbed feet of shore birds resulted from the repeated stretching of the feet, not from an inherited gene.

6. 3. What was Lamarck’s theory? • Similar species descended from a common ancestor- thus, living species were descended from similar extinct species evident in the fossil record.

7. 5. What part of Lamarck’s theory is useful today? • He was the first to state that organisms change over time and that new types of organisms are modified descendants of older organisms.

8. Charles Darwin (a.k.a. Chucky-D) • 1809-1882 • Proposed that species were modified by natural selection.

9. 6. What is natural selection? • Organisms best suited to their environment reproduce more successfully than other organisms. • Organisms with favorable traits increase in population.

10. 7. Who are the two scientists who proposed it? • Charles Darwin • John Henslow

11. 8. Define population. • An interbreeding single species group.

12. 9. Describe Darwin’s background before his voyage on the beagle. • He first attended medical school and was grossed out by the sight of blood • Then he enrolled in school to be a clergy man, but was unable to council people. • After failing at both he did not know what he wanted to do . • Then he was offered the voyage of a lifetime……

13. H.M.S. Beagle • He was a naturalist for the expedition • It was a 5 year mapping and collecting expedition. • Toured South America and South Pacific.

15. 10. What is uniformitariansim • The idea that geological principles that guide earth today are the same that they have been in the past.

16. 11. What did Darwin reason was an organisms response to the changing environment? • He reasoned that the changing environment changed habitats. • A population would have to change also to survive.

17. 12. What did he say about he pace of change? • That it would be slow and hard to detect by humans

18. 13. What was note worthy about he Darwin finches? • Each finch species had a specialized bill suited for its diet.

20. 14. What did Darwin conclude about the finches? • That despite the bill, each finch was so similar he concluded that they must share a recent common ancestor. • Meaning they were descended from the same species.

21. 15.Where is Darwin’s theory explained? • The Origin of the Species • 1858

22. 16. What are the two parts of Darwin’s theory? • Decent with Modification • Modification by Natural Selection

23. 17. Explain “descent with modification”. • Newer organisms in the fossil record are actually descendants of older species

24. 18. Darwin reasoned that all living things… • Are descended from one or a few original types of life.

25. 19. What states how evolution occurs? • Modification by Natural selection

26. 20. What is the environmental affect on population growth? • Environment limits the growth of populations by increasing the rate of death or decreasing the rate of production or both.

27. 21. What determines if a trait will be passed on? • If a trait both increases the reproductive success of an organism and is inherited it will be passed on.

28. 22. What is fitness? • An individual with high fitness is well adapted to its environment and reproduces more successfully than an individual with low fitness.

29. 23. What is adaptive advantage? • A favorable trait is said to give the organism a better chance at reproduction and passing on traits.

30. 24. What is the effect of environmental change? • It causes populations to rapidly adapt to new conditions, if the change is too extreme, and the population is unable to adapt, it will become extinct.

31. The Galapagos

36. Warm water penguins

37. Blue Footed Boobies!

41. Evolution in Process

42. 1. Define homologous. • Similar features that originated in a shared ancestor • Example: beaks of birds; forelimbs of animals.

44. 2. Give a specific example. • The forelimbs of the penguin, alligator, bat, and human all derive from the same embryological structures.

45. 3. Define analogous (features). • Serve the same function and look some what alike. They derive from different structures in development.

46. The wings of humming birds and humming bird moths. 4. Give one example.

47. 5. Define vestigial feature. • Apparently useless features, that no longer serve a function

48. 6. Give two examples. • Human tail bone, and appendix • Snakes have limb bones

49. Whale of a tale • Whales have pelvic bones

50. 7 What clues do vestigial structures provide? • Whales probably descend from a land animal that had legs. • These structures show body parts which function is no longer necessary for reproductive success (survival).