Evolution of Primates and Human Ancestry

1. C 16- Primate Evolution Pp. 420-441

2. Content • 16-1 Primate Adaptation & Evolution • 16-2 Human Ancestry

3. Primate Adaptation & Evolution • Primates – group of mammals including lemurs, monkeys, apes & humans. • Common traits – opposable thumbs, binocular vision, large relative brain volume, flexible arms & joints, grasping feet.

4. Primate Origins • Strepsirrhines earliest fossils 50 -55 MYA • Current ex. Lemurs, aye-ayes in Africa & SE Asia • Typically small, nocturnal animals w/ big eyes

5. Primate Origins • Haplorhines – tarsiers & anthropoids such as hominoids including apes & humans, Old & New World monkeys • More complex brains, more upright posture, different skeletal features.

6. Primate Origins • New World Monkeys- 30 -35 MY old fossils • Central & S America • Arboreal with prehensile tail

7. Primate Origins • Old World Monkeys • Arboreal or terrestrial without prehensile tails; includes colobus monkeys, macaques, baboons. • Adapted to many varied environments from hot, dry savannas to cold mountain forests. Fossils 20 – 22 MYA

8. Primate Origins • Hominoids- apes (orangutans, gibbons, chimpanzees, bonobos, gorillas) or humans • Lack tails, have long, muscled forelimbs, large brain capacity • Oldest anthropoid fossils 37 – 40 MYA

9. Primate Origins • By examining DNA of modern hominoids, scientists have evaluated the probable order in which apes and humans evolved. • Chimpanzees share the closest common ancestor w/ humans. Jane Goodall

10. 16.2 Human Ancestry • In Africa, 5-8 MYA, a population ancestral to chimpanzees & humans diverged. • May have been due to environmental changes. • Bipedal hominids had a survival advantage.

11. Human Ancestry • Australopithecus africanus discovered by Raymond Dart 1924 with features of both apes & humans. • Braincase & facial structure of ape & position of foramen magnum like humans • 2.5-2.8 MYA

12. Human Ancestry • Paleoanthropologist Donald Johanson (1974) “Lucy” Australopithecus afarensis found in E Africa 3-4 MYA • Although braincase was more like chimp, pelvic bone was more humanlike.

14. The Emergence of Modern Humans • <embed src="http://sciencestage.com/flvplayer.swf" quality="high" width="450" height="367" name="VideoPlayer" type="application/x-shockwave-flash" pluginspage="http://www.macromedia.com/go/getflashplayer" FlashVars="file=http://www.youtube.com/watch?v=k-4FHl1-Jcs&width=450&height=367&displaywidth=450&displayheight=367&overstretch=true&showfsbutton=false&image=http://sciencestage.com/uploads/thumbs/40cairqx3is83z4u.jpg&link=http://sciencestage.com/v/5586/walking-with-cavemen-part-2-blood-brothers-3-of-3.html&linktarget=_blank&backcolor=0xFFFFFF" wmode="transparent" border="0"><a href="http://sciencestage.com/v/5586/walking-with-cavemen-part-2-blood-brothers-3-of-3.html">Walking with Cavemen - Part 2 Blood Brothers 3 of 3</a>></embed> • Handy man or Homo habilis • 1.5 -2.5 MYA Homo habilis skull

15. Primate Adaptation & Evolution • Handy man or Homo habilis • 1.5 -2.5 MYA • Discovered 1964 by Louis & Mary Leakey in Olduvai Gorge, Tanzania in Africa • Earliest known hominid to use tools Homo habilis

16. The Emergence of Modern Humans • Homo erectus 1.5-1.8 MYA “upright human” • Larger brain, more human face, prominent brow ridges, lower jaw w/ no chin • Evidence suggests hunters lived in caves Africa, Asia, & Europe

17. The Emergence of Modern Humans • H. sapiens 100,000 – 500,000 YA • Neandertals 35,000 – 100,000YA during ice age, had religious views & spoken language • Cro Magnon more modern with similar size to humans, toolmakers & artists

18. Emergence of Modern Humans • Humans haven’t changed much in past 200,000 years. • Africa, Europe, Asia, North America • 10,000-8000 YA native Americans had establish settlements w/ domesticated animals & farming