Lecture 13 - Hyper-megadont Archaic Hominins Flashcards
(21 cards)
Paranthropus spp
Paranthropus spp characteristics
- extreme chewing amchines
- very thick enamel
- enlarged posterior teeth
- deep & broad mandibular corpus & ramus
- flared zygomatics
- orthognathic
- sagittal keel/crest
Paranthropus spp
Paranthropus robustus general information
- Blauuwbank Valley, South Africa
- c. 1.5-2 Ma
- first Paranthropus ever found
Paranthropus spp
Paranthropus robustus VERSUS
Au. africanus
- larger brain, face, posterior teeth in P.
- anterior teeth are smaller in P.
- some P. specimens have sagittal keel, but no A. africanus
Paranthropus spp
Paranthropus robustus VERSUS
A. africanus interpretations
- ‘single species hypothesis’
- they are sister taxa and belong to a distinctive souther African clade
- taxa belodnt o different clades - P. robustus is the sister taxon of P.boisei
Paranthropus spp
P. boisei general info
- Eastern Africa
- c. 2.3-1.2 Ma
Paranthropus spp
P. boisei general characteristics
- the most robust of P.
- sagitall crest is smaller and more anterior than P. aethiopicus
- less prognathism than P. aethiopic
Paranthropus spp
P. boisei occlusal view of the palate
OH5
- post-canine teeth larger than other P. species
- reduced anterior teeth - crowding
- thicker palate
- thick enamel
Paranthropus spp
P. boisei mandible
- enlarged mandibular corpus and ramus
- same posterior/anterior relationship in teeth
Paranthropus spp
P. boisei sexual dimorphism
- relatively high
- presumed males are larger-bodied
- not as extreme as in Au. afarensis
- most size difference (not shape)
Paranthropus spp
P. aethiopicus general info
- Eastern Africa (Ethiopia)
- 2.5-2.7 Ma
Paranthropus spp
P. aethiopicus characteristics
- well-developed sagital and nuchal crests
- prognathism
- relatively small brain
- forward-projecting zygomatics
Paranthropus spp
P. aethiopicus link to P. boisei
- robust morphology but to a lesser degree
Paranthropus spp
P. aethiopicus link A. afarensis
- large incisors
- more prognathism
- sagittal crest is more posterior (and merges with the nuchal crest)
Aus. garhi
Au. garhi general info
- 2.5 Ma
- Eastern Africa
- Bouri, Middle Awash, Ethiopia
- relatively few fossils
- discovers claim it is an ancestor of Homo
Aus. garhi
Aus. garhi characteristics
- large postcanine teeth, but enamel not thick (primitive)
- longer femur than in A. afarensis (derived)
- large anterior teeth (primitive)
Aus. garhi
early evidence of tool use
- Bouri, Ethiopia
- ~2.5 Ma
- percussion & cutmarks on bone
- no tools found
- not directly associated wiht the hominin but A. garhi is the only hominin at the site
Aus. garhi
conclusion?
- too few fossils to draw a definite conclusion
- possibly a late A. afarensis or a female P. aethiopicus - megadont grade
- possible ancestral to Homo
–> longer femur, larger anterior teeth, tool use
Paranthropous spp.
postcrania??
- not many postcrania have been identified
- still debated, likely not to be very different from other hominins (i.e. not robust)
- pelvis appears to have been similar to Aus.
- some postcrania attributed to H. habilis may in fact belong to Paranthropus
- stone and bone tools at sites dominated by P. robustus remains
- pad-to-pad grip
early evidence of tool use - digging tools
- 1.8 - 1 Ma, Swartkrans, South Africa
- polished bone & horn core (used as is)
- associated with both Paranthropus and early Homo
P. spp
paleocology
- termites (bone tools)
- isotope studies = C4-based diets
P. spp
end of the lineage
- similar dietary flexibility as Homo
- long-held idea that they were specialists and that Homo was a generalist
- possible direct or indirect competition with Homo
- differences in tool use
