Homo habilis Postcrania

Homo habilis
Comparison to Australopithecines
q “handy man”
q Found in East & South
Africa
q Same deposits as Zinj,
found by Leakeys
q Lived about 2 mya
q Close enough to us to
be in our lineage
q Contemporary of robust
Australopithecines
Postcrania
w Reduction in cheek tooth size (posterior dentition)
w Smaller face
w No saggittal crest
w Increased cranial size
Reconstruction
p Shorter toes
h about 4’5” tall
h maintains significant
sexual dimorphism
h a great deal of
variation, perhaps
more than one
species
p More dexterity in thumb
h 500-830 cc
p Long forelimbs
h ~2.5 - 1.5 mya
p Not much to work with
p Bigger femoral head
than australopithecines
p Pelvis a bit more flared
Olduwan Tools
o 1st credited to A. boisei
o reason for “habilis”
o cut marks on animal
bones
o crude choppers
o scrapers
o transported
o scavenging
Scavenging
Hunting vs. Scavenging
Lewis Binford -W Majority of bones are lower extremeties
W Left after carnivore feasts
W Tools are work well for getting a marrow cavity
Pat Shipman -W Microscopic cut marks
W Carnivore tooth marks over cut marks
Gathering
A. Robustus & H. Habilis
N Adaptive experiments
N Open woodlands & savannas of Africa
N Environment changes
N Not enough room for 3 upright hominids
N Pushed into more marginal environments
N More generalized anatomy succeeds
N No need for violent confrontation in this scheme
N Ecological competition, environmental change
N Robust australopithecines were successful
W Cut marks not at the joints
W Omnivore dental wear patterns