1. Chapter 1
Science of Zoology and Evolution of Animal Diversity

2. Before Darwin

3. Jean Baptiste Lamarck
Lamarckism: inheritance of acquired characteristics
Transformational view of evolution
Not supported.

4. Sir Charles Lyell Uniformitarianism
Laws of physics and chemistry remain the same
Natural processes which acted in the past will continue to act.

5. Thomas Malthus Concerned with human population growth
People tended to reproduce faster than their food supply, and are forced to compete for existence.

6. Charles Darwin
Naturalist who combined the ideas of Malthus, Lyell and others to form the theory of evolution.

7. DARWIN’S THEORY OF EVOLUTION
A sea voyage helped Darwin frame his theory of evolution
On his visit to the Galápagos Islands Charles Darwin observed many unique organisms

8. Darwin’s main ideas can be traced back to the ancient Greeks
Aristotle and the Judeo-Christian culture believed that species are fixed

9. In the century prior to Darwin the study of fossils suggested that life forms change
Geologists proposed that a very old Earth is changed by gradual processes

10. While on the voyage of the HMS Beagle in the 1830s Charles Darwin observed similarities between living and fossil organisms and the diversity of life on the Galápagos Islands
North America
Great Britain
Europe
Asia
ATLANTIC OCEAN
PACIFIC OCEAN
Africa
PACIFIC OCEAN
Equator
The Galápagos Islands
PACIFIC OCEAN
South America
Pinta
Genovesa
Marchena
Australia
Santiago
Equator
Andes
Cape of Good Hope
Daphne Islands
Fernandina
Pinzón
Tasmania
New Zealand
Isabela
Santa Cruz
Cape Horn
Santa Fe
San Cristobal
Tierra del Fuego
40 km
Florenza
40 miles
Española

11. Darwin’s experiences during the voyage of the Beagle helped him frame his ideas on evolution

12. Darwinian Evolutionary Theory: The Evidence
1) Perpetual change
2) Common descent
3) Multiplication of species
4) Gradualism
5) Natural selection

13. I. Perpetual Change
Darwin noticed fossils of extinct marine organisms thousands of feet above present day sea level.

14. The Burgess Shale

19. Before the Scientific Method
People based their beliefs on their interpretations of what they saw
Without testing their ideas
Rather, their conclusions were based on untested observations.

21. Snakestones!

22. Some fossils you can not refute.

23. The Baltic amber deposits range between 35 to 40 million years old and is the largest source of amber yet discovered.

24. So What do these Fossils tell us?

25. Geological Time
Long before the earth’s age was known, geologists divided its history into a table of succeeding events based on the ordered layers of sedimentary rock.

26. The fossil record reveals that organisms have evolved in a historical sequence

27. Evolutionary trends
The fossil record allowed Darwin to view evolutionary change across the broadest scale of time.
Animal species typically survive approximately 1 million to 10 million years, before going extinct.

28. I. Perpetual Change
Darwin noticed fossils of extinct marine organisms thousands of feet above present day sea level.
Darwin also worked on the change of animals under domestication by humans (artificial selection).

29. Darwin found convincing evidence for his ideas in the results of artificial selection
The selective breeding of domesticated animals

30. I. Perpetual Change
Darwin noticed fossils of extinct marine organisms thousands of feet above present day sea level.
Darwin also worked on the change of animals under domestication by humans (artificial selection).
He combined these two observations to form the idea that organisms are constantly changing through time.

31. II. Common Descent
Whereas Lamarck believed in multiple origins of life, Darwin believed that all life originated from a single common ancestor.

32. Thousands to millions of years of natural selection
Darwin proposed that living species are descended from earlier life forms
African wild dog
Coyote
Wolf
Fox
Jackal
Thousands to millions of years of natural selection
Ancestral canine

33. Hi There How are You!!!

35. 6-11, p 110

36. Horses from Eocene to present (II)

37. How many species of horses are there?

38. Burchell's Zebra (Equus quagga)
Mountain Zebra (Equus zebra)
Grevy's Zebra (Equus grevyi) 

39. Asiatic Wild Asses - Kulan and Onager (Equus hemionus) - Kiang (Equus kiang)
African Wild Asses - African Wild Ass (Equus africanus)

40. Przewalski's Horse (Equus caballus)

41. So what do these horse fossils suggest?

42. Throughout the history of all forms of life, evolutionary processes generate new characteristics that are then inherited by subsequent generations.

43. II. Common Descent The evidence Darwin used was homology:
Whereas Lamarck believed in multiple origins of life, Darwin believed that all life originated from a single common ancestor.
The evidence Darwin used was homology:

44. Homologies
Homologies: Anatomical structures within different organisms which originated from a structure or trait of their common ancestral organism.

45. Figure 1.16 Humerus, Radius and Ulna, “Hand”, p 17

47. What are these animals?

48. Analogous Structures
The evolution of superficially similar structures in unrelated organisms is called convergent evolution.

49. So What?

50. Theory of Common Descent is Testable
Like all good scientific theories, common descent makes several important predictions that can be tested and potentially used to reject it.
According to this theory, we should be able to trace the genealogies of all modern species backward until they converge on ancestral lineages shared with other species, both living and extinct.