Lecture 14 - the origin of modern humans and 'out of Africa' 2

Question 1

when did the first molars occur?

Answer 1

4.6ma

Question 2

what are sapiens the sister group to?

Answer 2

neanderthals

Question 3

neanderthals: key facts

Answer 3

• evolves from H. heidelbergensis
• adapted to cold and routine heavy work
• brain = 1450cc (bigger than humans but low EQ)
• larynx structure suggests limited speech
• practiced ritual burials - helps with fossilisation
• produced stone tools and worked wood
• very robust
• very intelligent

Question 4

2 models for human evolution:

Answer 4

1. out of africa 1 - multi regional hypothesis:
   - 2ma - erectus migrates out
   - Africa serves as the source of modern humans
   homo sapiens evolve in Africa, Asia and Europe
2. out of Africa 2
   - 200,000 ya sapiens evolve in Africa
   - replaces all archaic species
   - regional differences are shallow - maximum 100,000 years and just evolved differently

Question 5

when did neanderthals die off?

Answer 5

40,000 - 27,000 ya in an East - West progression

- due to either competitive replacement or genocide by Homo sapiens

Question 6

Denisovian man

Answer 6

• 41,000 ya

- evidence of interbreeding

Question 7

Hobbit people of Indonesia key facts:

Answer 7

• Homo floresiensis
• up to 1ma
• 1m tall, 30kg, 417cm cubed brain
• primitive tools and fire
• most likely dwarfed hominin evolved from erectus due to similar primitive foot

Question 8

evidence from molecular biology:

Answer 8

• more diversity in Africa than rest of world put together
• suggests sapiens evolve in Africa and diversify by a smal number of Africans moving out and diversifying
• mitochondrial eve hypothesis - molecular clocks

Question 9

when was there population fragmentation in Africa?

Answer 9

100,000ya

- leads to 3 different `world populations