Section 16.1 Human Evolution

1. Section 16.1Human Evolution

2. Objectives • Recognize the adaptations of primates • Compare and contrast the diversity of living primates • Distinguish the evolutionary relationships of primates

3. Human Evolution • Primates: adapted for an arboreal (tree-dwelling) existence. • Primates range in size from the 30-gram (1 oz) Pygmy Mouse Lemur to the 200-kilogram (440 lb) Mountain Gorilla.

4. Primate Classification • I. Prosimians- Lemurs and tarsiers. • Cat-like face, large eyes • Oldest primate: Purgatoriosus (squirrel sized).

5. II. Old world Monkeys (tails) • Ex. Baboons, Mandrill • From Africa and Asia • Larger than other primates.

6. III. New World Monkeys (flat-nosed) • Ex. Howler monkey, pygmy marmoset (world’s smallest monkey) • Smaller than other primates • Exist in Central and South America

7. IV. Great Apes • Larger-bodied, no tail • Primarily ground dwelling

8. A) Orangutans • orang hutan, meaning "forest person". • (orange-man) • Borneo (Asia)- found only Asia

9. B) Gorilla • Largest living primate • Central Africa • Mountain gorilla • Lowland gorilla • The DNA of gorillas is 98%–99% identical to that of a human

10. C) Chimpanzees and Bonobos • West and central Africa, Congo river • species are the closest living relatives to humans • The Common Chimpanzee has an omnivorous diet, a troop hunting culture based on beta males led by an alpha male, and highly complex social relationships.

11. D) Humans • DNA evidence indicates that modern humans originated in east Africa about 200,000 years ago • Humans have a highly developed brain, capable of abstract reasoning, language, introspection and problem solving.

12. Human Ancestors • I. Australopithecus afrensis: southern ape-man, a far region of Ethiopia • Had a small brain size

13. Lucy (Australopithecus) • Fossil discovered by Don Johansen • Oldest- known upright waling hominid- (means human) • Shorter than modern humans • Lived between 3 and 5 million years ago

14. Characteristics of Lucy • 1 meter tall • About 60 lbs Brain size of Lucy • 450 cc or cm 3 (cubic centimeters) • (1cc=1ml or 450 grams or ½ pound

15. Proof of Bipedalism • Bipedal: Walked upright on two legs • Evidence: • Locking knee cap • Straightened spine • Broader hip • Forarmen magnum is the bottom of the skull (skull hole)

16. Advantages of upright walking • Stand taller • Move more efficiently, long distances • Freed up hands for: • Food gathering • Defense-weapon and tool use

17. Lucy Facial Features: • No forehead • Heavy brow ridge • Wide flat nose • Projecting (prognathic) jaws • Human-like teeth, no canines

18. II. A africanus • 3.6 -2.4 MYA (million years ago) • Bipedal • 60-90 lbs • Human-like teeth • Sexual dimorphism-difference in size and structure between the genders • Fossil- “Taung Baby’ • Raymond Dart- 1924

19. Africanus- gracile • Robust-A. robustus • A. boisei side branch (not our ancestor) • Large jaws and molars for eating nuts and roots (side note) Gracile: skinny, thin, small, graceful Robust: husky, fat

20. III. Homo habilis • “handy man” • First stone tool users • Louis Leakey:1964 • 750 cc/750 mL- brain size • Lived 1.8- 2 MYA • Smaller molars • Scavengers not hunters • Tools used to scrape meat or break bones for marrow

21. IV. Homo erectus • “Upright man” • 1.6 million – 250,000 years ago • Evolved to be very “Human Like” • Skeleton: longer and stouter • Height: 6 ft • Tool Users: hand axe • Lived in family groups • Hunted larger game • First fossil: 1891 “Java Man”

22. Migrated out of Africa • Fossils have been found in Spain, Russia, Indonesia, and Middle East • First to use fire

23. Out of Africa: Homo sapiens evolved in Africa and migrated out. The different races represent slight regional differences

24. Multi Regional Theory • Homo erectus migrated out an evolved independently in the different races of homo sapiens.

25. V. H. neandertalenis Neanderthal man formerly a subspecies of H. sapiens • 150,000-30,000 years ago • Short, stocky • 5 ft tall • Large, broad nose • Well adapted for cold • Aggressive hunter • Not a direct ancestor of H. sapiens

26. First to bury their dead • Stones marked their graves

27. Neanderthal Extinction Coincides with the appearance of modern humans in Europe • Killed by humans • Interbred with humans • Infected by human diseases • Out-competed by modern humans/ out-smarted by early humans

28. VI. Homo sapiens • “Wise Humans” • Archaic H. Sapiens: • (Ancient) Appeared 150,000 years ago • He did not seem to have culture, or creativity • Did evolve in Central Africa

29. VI. Homo sapiens (continued) • Modern Humans: • Appeared 50,000 years ago • Highly advanced tool making • Hunter gatherers • Agriculture and civilizations

30. Alternatives • Anti Evolution: beliefs which try to debunk science. • Pseudo Science: not based on scientific method. • Anomalous: doesn’t fit the accepted theory • Anachronism: Something out of place in time

31. creationism • A literal belief in the biblical account of Creation as it appears in the Book of Genesis. Creationists believe that the creation of the world and all its creatures took place in six calendar days; they therefore deny the theory of evolution.

32. intelligent design • The assertion or belief that physical and biological systems observed in the universe result from purposeful design by an intelligent being rather than from chance or undirected natural processes.