Primate Origins

Primate Origins - Primate Origins Geologic Time Scale In...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Primate Origins Geologic Time Scale In this changing landscape, why the emergence of Primates? Arboreal Theory 0. Life in the trees accounts for primate characteristics 1. Insectivores looking for food in the trees favor eye sight over smell 2. Tree climbing favors grasping hands and feet 3. Jumping from branch to branch favors 3D vision 4. Shift in diet to seeds, fruits, and leaves lead to the Primates Visual Predation Theory 0. Matt Cartmill asked, "How do we explain squirrels?" 1. Primate traits advantageous for hunting insects on slender branches 0. 3D vision to judge distance to prey 1. Grasping hands and feet to move through branches and grab insects 2. Sussman adds nocturnal predation as important factor Paleocene Primates (65 mya) 3. Found in the New World 4. Plesiadapis 2. Looked more like insectivore or rodent 3. Lacked many primate characteristics 0. No stereoscopic vision 1. Claws instead of nails 2. No grasping hands/feet 4. Did have teeth suggestive of omnivorous diet 5. Archaic primates Eocene Primates (55-38 mya) 5. Primates of modern aspect 6. Found in North America, Europe, Asia, Africa 7. Two types 0. Adapids lemur-like 0. Slow climbers as well as leapers 1. Mostly leaf and fruit eating 1. Omomyids tarsier-like 2. All show leaping adaptations 3. Probably insect and fruit eating Oligocene Primates (34-24 mya) 5. Fayum, Egypt 6. Riverine forest and swamp 6. Two types 7. Parapitecids 3. Monkeylike but some prosimian-like traits 0. 3 premolars 8. Propliopithecids 4. Dental formula of modern catarrhines Oligocene Primates (34-24 mya) 8. Parapitecids 2. Small squirrel monkey size 3. Fruit and seed eaters 4. Probably ancestral to NWM 4. Island hopping?, rafting? 9. Propliopithecids 5. Aegyptopithecus 5. Small brain with large muzzle 6. House cat size 7. Marked sexual dimorphism 8. "Dental ape" Miocene Primates (24-5 mya) 7. "Age of Apes" 8. Habitat 9. Early Miocene Africa free floating 10. By mid-Miocene (~16 mya) land bridge with Eurasia 5. Adaptive radiation 11. Changing environment 6. Becoming drier 7. Forests disappear and replaced by woodlands and/or savanna Early Miocene Proto-Apes 9. Proconsul 12. About 20 mya 13. Bigger than Oligocene anthropoids 8. Gibbon to female gorilla sized 14. Lacked a tail 15. Arboreal quadruped 9. Lacked specialization for suspension 16. Fruit and/or leaf eating Middle Miocene Apes 10. 16-10 mya 11. First definitely hominoid fossils 12.Pierolapithecus 13.Kenyapithecus 17. Spain 18. Maboko Island and Kenya Middle Miocene Apes 14.Kenyapithecus 19. Teeth and faces resemble more modern hominoids 20. More terrestrial than previous forms 21. Thickly enameled teeth and robust jaws 10. Hard tough foods 22. No brachiation Middle Miocene Apes 15.Pierolapithecus 23. Capable of brachiation 11. Monkey form 24. Good candidate for ancestor of later forest-dwelling apes Late Miocene Apes 10. Fossils from Europe, Asia and Africa 11. Climate is turning cooler and drier 6. Environmental changes favored monkeys over apes 12. Two types 7. Sivapithecus 9. Asia 8. Dryopithecus 10. Europe 13. Specializations for suspensory locomotion Sivapithecus 14. 13-8 mya 15. Flat, thickly enameled molars 16. Smaller canines 17. Less sexual dimorphism 18. Lived in mixed woodland-grassland environment 19. Diet? 9. Coarse grasses and seeds? 10. Fruit with coarse pits Gigantopithecus 16. One of the Sivapithecids 17. Found only in the forests of southeast Asia 18. Bamboo eater Dryopithecus 19. 15 10 mya 20. Chimp sized 21. Arboreal 22. Omnivorous 23. Thinner tooth enamel 24. Lighter jaws 25. Pointed molar cusps 26. Evolutionary relationships? Divergence of Hominids 27. Lack of fossil from the 13.5 5 mya period 28. "Sudden" appearance of bipedal hominids at 5 mya 29. Molecular clock 25. Based on similarities in blood proteins 26. Assumes molecular changes occur at constant rate 27. "neutral" characteristics Molecular Clock ...
View Full Document

Ask a homework question - tutors are online