Final Flashcards
What are the two heuristic groups of australopithecines?
Gracile and robust
What is ardipithecus dated as and where was it found?
4.4 myr
Ethiopia
Why was ardipithecus classed as a hominid?
Biped - pushed off second toe
Still has abducted toe
What was the brain size and face shape of ardipithecus?
- 300- 500 cc
- less projecting then chimp
What is different about ardipithecus’ canines?
- Smaller canines then a chimp
- largest canines of the hominid group
- less sexually dimorphic than chimps
Example of gracile?
Australopithecus Africanas
Taung child
Gracile morphological traits
- Smaller canines
- less projecting face
- larger molars
- same brain size as a chimp 400 - 500cc
Sexual dimorphism of australopithecine
- Large sexual dimorphism
- hints to polygynous mating system
Where and when were “robust” australopithecines?
- Bosei
East Africa
2.1-1.1 Mya - robustus
South Africa
1.8 -1 mya
Dentition of robustus
Small incisors “peg-like”
Enormous molars and mandible
Why does robustos have a wide face
- Small front teeth
- huge molars
Sagitta crest for large chewing muscles
Large zygomatic arch
Information on transitional phase between late Australopithecus and early homo
- Africa - 2 million years ago
- bigger skulls OR more modern-shaped faces
- never both
- small bodies
Habilines
- 1.9 Mya from East Africa
- 510cc cranial capacity
- smaller face vs Australopithecus
- small front and back teeth
- projecting brow ridge
- low post-orbital constriction
- stone tools = unknown
“Rudolfensis”
- 1.9 Mya East Africa
- 775 cc
- large Australopithecus face
- large molar and front teeth
- No brow ridge
Stone tools unknown
Homo ergaster unique
- 1.8 Mya in Africa
Unique in morphology in technology
Ergaster example and post cranial construction
Nariokotomc boy
Males
- bigger bodies
- 1.65 myr
- thin
- heavily muscled
Advantages of ergaster morphology
- Heat adaptation
- hunting-related running
Teeth morphology of ergaster and why
Front teeth and molars get smaller
Different diet perhaps due to processing of food with fire and tools
Projection of ergaster face
Less projection
Brow ridge of ergaster
Large and projecting
Also called suprorbital sulcus