4/13 Lecture - Hominin Evolution

Question 1

Why become Bipedal?

Answer 1

Environment is changing ->
Expansion of grasslands in East Africa from 5MYA to present

• Compromise for living in a savanna & forest/woodlands

Question 2

Paranthropus boisei

Answer 2

1. 2 - 2 MYA
   - “robust Australopithecine”
   - Extinct ~ 1MYA
   - Orthognactic
   - EXTREME MEGADONTY -> Enormous cheek teeth
   - Sagittal crest (Due to large chewing muscles pushing on skull)
   - Sexual Dimorphism

Question 3

Olduvai Gorge

Answer 3

Found Oldowan Tools

And Paranthropus boisei

Question 4

Homo habilis

Answer 4

“handy man”
Leakeys combination of multiple specimens in Olduvai Gorge*
- Larger brain than Australopithecus
- smaller teeth than Au.
- Hand w/ good manipulative abilities
Conclusion: H habilis was tool maker/user at Olduvai , Not Paranthropus.

Question 5

KNM - ER 1470

Answer 5

• 1.9 MYA
  - male
  - orthognactic
  - LARGE EndoCranial Volume (ECV)
  - megadonty

Question 6

KNM - ER 1813

Answer 6

• 1.9 MYA
  - Female
  - orthognactic
  - small ECV
  - small cheek teeth

Question 7

Homo Habilis* (Supposed to have)

Answer 7

• Larger brain than Australopithecus

- smaller teeth than Au.

Question 8

Most researchers say what about the KNM - ER species?

Answer 8

TWO SPECIES!

1470 -> big brain/big teeth -> Homo rudolfensis

1813 -> small brain small teeth -> Homo habilis