First Appearance of AMH

1. First Appearance of AMH • Africa about 195 kya (Omo, Ethiopia) • Western Asia about 90kya • South Asia and Australia 50-60 kya • Europe and N. Asia 40 kya • Americas 13.5 kya

2. AMH characteristics • 5-6 ft. Extremely variable • 100-200 lbs. Extremely variable • 1330 cc (1000-2000cc) • Enhanced working memory

3. Small face • High vaulted globular cranium • small discontinuous, arched brows • Chin • Canine fossa

5. Vocal tract with low larynx and long pharynx • Reduced body mass (compared to archaic humans) • Linear physique • Short pubic ramus but large pelvic inlet

6. Premolars and molars both small relatively and absolutely • Smaller and weaker jaws than archaic humans

8. Adaptations and changes to AMH driven by selection for complex speech? • Neurocranial globularization • Facial reduction • Development of modern proportions in vocal tract

9. Migration Models • “Out of Africa” or Replacement • AMH evolved recently in Africa • Migrated to rest of world • Supplanted existing hominids with little or no interbreeding (gene flow) • Cladogenetic speciation

12. Multiregional model • AMH did not evolve in one region, but different traits evolved in different regions and spread to other regions by gene flow • Gene flow prevented populations from speciation, but allowed regional differentiation. • Anagenetic speciation

14. Models Compared • Multiregional • Homo sapiens evolved simultaneously from Homo erectus pops in Africa, Asia, and Europe • “Out of Africa” • Homo sapiens evolved from Homo erectus in Africa and migrated out.

15. Fossil, genetic, and archaeological evidence favors “Out of Africa” theory but does not rule out some interbreeding between invading moderns and archaic resident pops in some geographical areas. • Therefore more of an “assimilation” model seems appropriate.

16. Mitochondrial Eve • mtDNA has high rate of evolution when compared to most nuclear DNA • Maternally inherited, no recombination, smaller effective population size

17. Modern Human Genetics • 94% of modern human mtDNA diversity is found within major geographic pops; 6% distinguishes pops. • Extant humans are not genetically diverse: • Human mtDNA is 1/40th as diverse as chimp mtDNA • One lowland gorilla pop holds more diversity than all 6 billion humans

18. Mitochondrial “Eve” Theory • Cann, et al. 1987 (Nature) • All modern humans have their mtDNA from a single female • That woman lived in Africa • She lived approx. 200kya

19. Hypothesis 1 • Inherent property of mtDNA to “coalesce” to a single form • This DOES NOT imply we’re from a single woman, only our mtDNA is. • Important point is when she lived.

21. Hypothesis 2 • May establish where humans evolved • mtDNA ancestor must have lived somewhere… • 2 lines of evidence • Cladograms (mtDNA) show African ancestral sequence • Africans are far more diverse in their mtDNA • Favors “Out of Africa” as multiregional theory predicts nearly equal genetic diversity in all Old World pops.

23. Summary of Genetics • Fossil evidence and DNA are consistent: AMH originated in Africa about 200kya • Fossil evidence may suggest sympatry in Middle East and Europe • Archaeology ambiguous, but consistent with African origin theory • mtDNA consistent with African origin theory • mtDNA and nuclear DNA of Neanderthals distinctive from AMH

24. Upper Paleolithic Technology • 90kya-35kya in Old World • Distinguished by blades • Bone, ivory, and antler utilized • Projectiles, punches, awls, needles, beads, etc.

25. Upper Paleolithic Behaviors • Compound tools • Sewn clothing • Portable art • Cave art • Tattooing?