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
Homo ergaster occipital bone
Also called nuchal torus
Hints to strong neck muscle
Could mean stranger sight
Sexual dimorphism in ergaster
Less sexual dimorphism
Could indicate pair- bonding
What are acheulean tools dated to
1.7 Mya
Attributes of Acheulean tools
Hints to a smarter animal
- multiple steps
- biracial flaking
- shows mental templating
Where did heidelbergensis live
- Evolved first in Africa
- spread to Europe and Asia
When did heidelbergensis live
800,000 - 200,000 kyr
What was the climate like for heidelbergensis
Colder
Anatomy of heidelbergensis to ergaster
Larger cranial capacity
Wider parietal bones
Sägittal keeling
Kept from ergaster
-Brow ridge
- thick cranial bone
- nuchal torus
Where did Neanderthals live
Europe below latitude 55°N
West to the edge of Siberia
South to the near East
When did Neanderthals live
200 - 29 kyr
What climate did Neanderthals live
Glaciers repeatedly spread and receded
Neanderthal “derived” features
- Double-arched, continuously thick brow ridge
- long low cranium “football”
- projecting midface
- by nose
- occipital bun
- retromolar gap
- no chin
Where and what did modern humans appear
- Appear in Africa
- 160 kyr
- 1450 cc
- round cranium “bowling ball”
- weak nuchal torus
- gracile, flat face
What is a mental trigon?
Triangle on chin
What is a mental trigonc
Triangle shape on chin
Mental trigon
Shape on chin
How is facial prognathism related to thesize of the anterior dentition
The larger the canines the more prognathism present
Why would tool use lead to a reduction in tooth and face size
More processed foods mean less need for such large zygomatic and large teeth
What are some hypotheses for the function of the Supra orbital torus
- Sweat
- fights
- sexual selection
Function and understanding from the nuchal torus
-For the neck muscles to attach to
- hunting
- carrying
What do the dental and cranial features of early homo show in difference from australopithacines
- Tools
- Fire
What could be evidence of interbreeding between Neanderthals and Homo sapiens
- Projecting middle face
- occipital bun
- brow ridge
What type of prognathism do Neanderthals have
Midfacial
Diastema
Gracile
What species does suprainiac fossa appear in
Neanderthals
What is the order of species
- Ardipithecus
- gracile
- robust
- habilines
- heidelbergensis
- Neanderthals
- ergastor
- sapien
What is a hominid and how does it differ from other apes
- Erect, bipedal, primate mammals
- less prognathism
- taller
-Bipeds - smaller canines and molars
Derived traits
Stone tool industries and which hominids areassociated with each
- Oldowan and archulean
- habilines = oldowan
- ergaster = archulean
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