Early Hominins

Question 1

Sahelanthropus tchadensis

Answer 1

L: Chad (East)
T: 6-7 mya

Question 2

S. tchadensis characteristics (5)

Answer 2

Hominin:
- more vertical face than apes
- smaller canines
- bipedal?

Primitive:
- small brain
- U dental arcade

Question 3

Orrorin tugenesis

Answer 3

L: Kenya (East)
T: 6 mya

Question 4

O. tugenesis characteristics (2)

Answer 4

femoral morphology indicative of bipedalism
- dental morphology similar to apes

Question 5

Ardipithecus kadabba

Answer 5

L: Ethiopia
T: 5.2-5.8 mya

Question 6

A. kadabba characteristics (3)

Answer 6

• intermediate canine size
• skeleton 45% complete
• woodland environment

Question 7

Ardipithecus ramidus

Answer 7

L: Ethiopia
T: 4.4 mya

Question 8

A. ramidus characteristics (7)

P vs H traits

Answer 8

P traits?
- ape-like prognathism
- relatively small brain, forwardly placed FM
- divergent big toe

H traits?
- reduced canine size
- min. sexual dimorph.
- pelvis - bipedal? –> short/broad illium (unlike chimps); ischial surface (like apes)
- lack suspensory & clinging features