Theory of Evolution

1. Theory of Evolution

2. EVOLUTION: change over time; the process by which modern organisms have descended from ancient organisms THEORY: a well-supported testable explanation of phenomena that have occurred in the natural world FOSSIL: the preserved remains of ancient organisms

3. What is biodiversity? Where did all these different organisms come from? How are they related?

4. The person who contributed the most to our understanding of evolution was ______________________ In 1831, at age 22, he joined the crew of the _______________ as a naturalist for a ________ voyage around the world. Charles Darwin H.M.S. Beagle 5 year

5. evidence During his travels, Darwin wrote thousands of pages in his journals, drew pictures of the things he saw, and collected a vast amount of ______________ that led him to propose a _______________________ about the way _____________. revolutionary hypothesis life changes

6. H.M.S. Beagle While on his voyage around the world aboard the ____________, Charles Darwin spent about one month observing life on the ________________. There, he encountered some unique animals, such as ______ and ________. Galápagos Islands finches tortoises

7. climates The Galάpagos Islands are close together but have very different _______. Some were hot and dry, with little vegetation. Others had more rainfall and were rich in vegetation Each island had its own _______ ____________ of plant and animal species. unique assortment

8. Giant Tortoises of the Galápagos Islands Pinta Tower Marchena Pinta IslandIntermediate shell James Fernandina Santa Cruz Isabela Santa Fe Hood Island Saddle-backed shell Floreana Hood Isabela Island Dome-shaped shell …while on the lush rainforest of Isabela Island, tortoises had short necks…

9. same species different isolated Darwin began to wonder if animals living on different islands had once been members of the ____________ that had developed _________ characteristics after becoming _______ from one another in different habitats.

10. James Hutton Ideas that shaped Darwin’s thinking: In 1785 ______________ proposes that the EARTH was _______ by _________________ occurring over __________ periods of time, and is _______________ old. shaped geological forces very long millions of years

11. Ideas that shaped Darwin’s thinking: In 1833 _____________ explains that the geological processes still _____________ have shaped Earth’s features over __________________. Charles Lyell occurring now long periods of time

12. SINCE THENTheory of Pangaea and continental drift Ideas that shaped Darwin’s thinking:

13. Georges Cuvier Ideas that shaped Darwin’s thinking: French naturalist _______________ developed his theory of catastrophes. He studied fossils and found that animal and plant species are destroyed time and again by deluges and other natural cataclysms. After each time and only after, new species evolved.

14. What is competition? Living things must compete for food, shelter, space, mates

15. Ideas that shaped Darwin’s thinking: _____________________ He observed that babies were being born faster than people were dying. He reasoned that if the human population continued to grow, sooner or later there would be _______________________. Thomas Malthus (1798) insufficient space & food

16. Jean-Baptiste Lamarck (1809) Ideas that shaped Darwin’s thinking: ___________________________ was one of first scientists to recognize living things _______________ and that all species were ________ from other species. Lamarck published his hypothesis of ________________________ the year Darwin was born. changed over time descended Inheritance of Acquired traits

17. The male fiddler crab uses its front claw to _________mates and fight off _____________. attract predators repeated Through _________ use, the front claw becomes ________. larger The fiddler passes on this __________ characteristic to its offspring acquired

18. What’s wrong with Lamarck’s hypothesis? Lamarck didn’t know about genes and how traits are ____________. If you lifted weights your whole young adult life, and then you had children, would your kids be more muscular? inherited NO! ________ traits can ____ be __________ to their offspring. NOT ACQUIRED PASSED ON

19. What’s right with Lamarck’s hypothesis? Lamarck was first to develop a scientific hypothesis about _________ and recognize that organisms are ________________________. evolution adapted to their environments

20. Match the letter of the idea with the man or men who proposed it: Malthus Hutton Lamarck Lyell • The earth is really old, and slowly changes • Living things pass acquired changes on to their offspring • Sooner or later growing populations run out of resources • Living things change slowly over time because of competition for resources, and pass those changes on to their offspring

21. c. Malthus Hutton a. Lamarck Lyell b. d. • The earth is really old, and slowly changes • Living things pass acquired changes on to their offspring • Sooner or later growing populations run out of resources • Living things change slowly over time because of competition for resources, and pass those changes on to their offspring

22. The fossil record Geographic distribution of living species Homologous body structures Similaritiesin early development Physical remains of organisms Common ancestral species Similar genes Similar genes Evidence of Evolution includes which is composed of which indicates which implies which implies

23. species diversity After Darwin returned to England in 1836 he filled notebooks with his ideas about _____________ and the process that he would later call _______. He did not rush to publish his ideas because they ________ with the fundamental scientific ______ of his day. He asked his wife to publish his ideas when he ___. evolution disagreed beliefs died

24. Alfred Russel Wallace Malaysia In 1858 another naturalist, _________________, wrote an essay describing his work in _______ that summarized the same ideas _____ had been thinking about for 25 years! Darwin http://www.thesecondevolution.com/wallace&darwin.jpg

25. Suddenly Darwin had incentive to publish the results of his work! In 1859 ____________________ presented _______ and proposed a ________ for evolution that he called __________________ On the Origin of Species evidence mechanism NATURAL SELECTION http://www.loc.gov/exhibits/world/images/s125.jpg

26. Isn’t evolution just a theory? A theory is a ____________, _______, explanation of phenomena that have occurred in the natural world, like the theory of __________________, ________, and _____________. well-supported testable gravitational attraction cell theory atomic theory

27. GENETIC VARIATION WHAT IS DARWIN’S THEORY? _________________ is found naturally in all populations

28. STRUGGLE FOR EXISTANCE WHAT IS DARWIN’S THEORY? ______________________ means that members of each species must ________ for food, space, and other __________. COMPETE RESOURCES

29. population less likely WHAT IS DARWIN’S THEORY? Some organisms in a ________ are ________ to survive.

30. SURVIVAL OF THE FITTEST WHAT IS DARWIN’S THEORY? _____________________organisms which are better adapted to the environment will ______ and________, passing on their _____. survive reproduce genes

31. survive and reproduce VOCAB Ability of an individual to ______ ____________ in its specific environment = ______ fitness

32. inherited characteristic chance of survival VOCAB Any ___________________ that increases an organism’s ______________ = _____________ ADAPTATION

33. WHAT IS DARWIN’S THEORY? Over time, natural selection results in ________ in the inherited characteristics of a __________. These changes ______ a species’ _____ in its environment. CHANGES POPULATION increase fitness

34. WHAT IS DARWIN’S THEORY? DESCENT WITH MODIFICATION ____________________________ suggests that each species has ___________, with ________, from other species over time. This idea suggests that all living species are ____________________, and that all species, living and extinct, share a _________________. DESCENDED CHANGES RELATED TO EACH OTHER COMMON ANCESTOR

35. Artificial selection EVIDENCE OF EVOLUTION: • ________________ • ________________ 3. _______________ 4. _______________ 5. _______________ 6. _______________ 7. _______________ Fossil record Geographic Distribution Homologous structures Embryology DNA See Natural selection happen

36. NATURE variation • ARTIFICIAL SELECTION WORKS • In artificial selection, ____________ • provides the _________ through • _________ and _________________ • and ______________ those traits that they find ______. mutation sexual reproduction humans select useful EX: We have selected for and bred cows to produce more milk,turkeys with more breast meat, etc.

37. Breeds of Dogs Chihuahua – bred from Techichi of Mexico by Mayans, had religious significance Saint Bernard – bred by monks around 1050 A.D. to rescue travelers of mountain passes in the Swiss Alps between Italy and Switzerland Irish Wolfhound – bred in Ireland to hunt wolves and elk Dachshund – bred in Germany as early as the 15th century to hunt badgers

38. How Do We Know Evolution Happens? 2. The Fossil Record – ______ are the _______ _________________ found in layers of rock in the Earth. Fossils remains of ancient organisms

39. How Do We Know Evolution Happens? The layers of rock tell the history of the _____, while the _____ found within the rock tell a history of ___. The fossils are thought to be the ________ as the rock they are found in. Earth fossils life same age

40. TRANSITIONAL FOSSILS HAVE BEEN FOUND

41. Fossil record shows change over time

42. If Darwin’s theory is supported you would expect to find ____________ yet _______________ living in a _________ region as they spread into nearby habitats and evolve. closely related different species geographic That’s EXACTLY what we do see!

43. THE GALAPAGOS TORTOISES Tortoises adapted to different habitats as they spread from the mainland to the different islands. = DIVERGENT EVOLUTION = ADAPTIVE RADIATION

44. GALAPAGOS FINCHES The _____ of Galapagos finches have ______ to eating a _____ of _____. beaks variety foods adapted

45. If Darwin’s theory is supported you would also expect to find _______________ living in ________ geographic regions but similar habitats becoming ________ as they adapt to ______________. different species far apart more alike similar ecosystems That’s EXACTLY what we do see!

46. Whales and sharks have a _____ body design even though they are very _______ organisms (one is a fish; the other, a mammal) because they have _________________ to living in a _____ environment. similar different independently adapted similar = CONVERGENT EVOLUTION

47. Whales are closely related to wolves, but don’t look or act much like them = divergent evolution Conclusion: The pressure of the environment drives evolution Whales are distantly related to sharks, but look and act more like them = convergent evolution

48. HOMOLOGOUS Structures 4. _____________________ They are parts of the body that are similar in structure to other species' comparative parts.

49. 4. Homologous Body Structures – Structures, like the limbs of vertebrates, look very _______, but are made from the __________, because they are made from the same clump of _____________ cells in the _______. different same bones undifferentiated embryo