Transcript H. habilis - CLAS Users

Australopithecus anamensis
• Named by Meave
Leakey and colleagues
in 1994
• crania, teeth &
postcrania
• 2 sites: Allia Bay &
Kanapoi
• ca. 4.2-3.9 Ma
A. anamensis
LOUIS LEAKEY
Paranthropus boisei
• O.H. 5
• discovered 1959
• “robust”
australopithecine -Zinjanthropus
• massive premolars and
molars
• tiny canines and
incisors
• “Human Cuisinart”
Robust australopithecines =
Paranthropus
• Late Pliocene - early
Pleistocene deposits
(2.5 -1 Ma)
• East & South Africa
• massive molars
• flatter, braoder, “dished”
faces
• poorly known postcranial anatomy
• similar in size to
Australopithecus
P. boisei -- female & male
KNM-ER 732
KNM-ER 406
Paranthropus aethiopicus
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KNM-WT 17000
The “Black Skull”
1985 discovery
W. Turkana (Kenya) &
Omo (Ethiopia)
• ca. 2.8 - 2.2 Ma
• primitive “robust”
australopithecine
Gracile
australopithecines
• Australopithecus
africanus
• A. afarensis
• A. anamensis
• A. bahrelghazali
Generalized jaws & teeth
Robust
australopithecines
• Paranthropus
robustus
• P. aethiopicus
• P. boisei
Specialized jaws & teeth
Australopithecus garhi
• 1999 discovery by
Asfaw, White and
colleagues
• 2.5 Ma Ethiopia’s
Middle Awash region
• garhi = “surprise”
A. garhi
• craniodental &
postcranial remains
(? association)
• Cranium:
– small brain
– prognathic face
– very large teeth
• Post-cranium:
– long legs
– long forearms
– < 5 ft tall
A. garhi
• Antelope remains
from nearby site with
cutmarks
• A. garhi or another
hominin species is
responsible (?)
• meat/marrow eating
at an early date -“hallmark” in human
evolution
Hominin Trends
Encephalization
Australopithecus
Homo
Dentition
Bone Marrow
22 March 2001
Kenyanthropus platyops nov. sp.
• Disc. 1999 by Meave Leakey
Kenyanthropus platyops nov. sp.
• “flat-faced man of Kenya”
• 3.2 to 3.5 Ma – western
Lake Turkana
• contemporary with “Lucy”
• new genus -- controversial!
• KNM-WT 40000 = holotype
Confused about taxonomy?
Hominidae
Australopithecinae
Homininae
African apes not
included
Australopithecines a
SUBFAMILY
Hominidae
Gorillinae
Homininae
Australopithecini
Hominini
Australopithecines a
TRIBE
http://www.mnh.si.edu/anthro/humanorigins/index.htm
Hominin Trends
Encephalization
Australopithecus
Homo
Dentition
Homo habilis Leakey et al., 1964
• Olduvai Gorge
– Beds I and II
– 2.0 - 1.6 Ma
• “Handy Man”
• Tool association
• Passes “cerebral
rubicon”
• Reduced molar size
Species based on ...
BED I Materials
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OH 4 -- isolated teeth
OH 6 -- cranial fragments
OH 7 -- mandible, parietals, hand bones (Type)
OH 8 -- partial foot
OH 10 -- toe bone
OH 35 -- tibia & fibula
OH 48 -- clavicle
OH 49 -- radius shaft
Species based on ...
BED II Materials
• OH 13 -- mandible, maxilla, cranial frags (Paratype)
• OH 14 -- cranial fragments
• OH 16 -- partial skull
The Cerebral Rubicon
Cranial Capacity (cm3)
A. africanus
P. boisei
H. habilis
H. erectus
x = 440
x = 515
x = 640
x = 1000
Defining Homo habilis
Craniodental Remains
• retreating chin region
• relatively large I & C
• small (narrow) molars
(relative to
Australopithecus)
• M3 smaller than M2
• Temporal lines never
meet in midline
• slight postorbital
constriction
Defining Homo habilis
Postcranial Remains
• hand bones robust,
prehensile
• stout big toe, adducted
• hand & forelimbs indicate
climbing & weight support
adaptations
OH 24 -- “Twiggy”
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Olduvai Gorge -- Lower Bed I
partial & reconstructed skull
female individual
cranial capacity ca. 590 cm3
(smaller than
Australopithecus)
• slight postorbital constriction
• domed forehead
• expanded parietal region
Oldowan “Chopper”
Technology
Homo habilis fossils (at one time or another)
Single Species Hypothesis
• C. Loring Brace & Milford Wolpoff
(University of Michigan)
• 1960s & early 1970s
• All anatomical differences between
hominin species is Intraspecific
variation, not Interspecific variation.
• Only one species of hominin can
exist at any one time.
Too much variation to
justify single species
Wolpoff (1964)
• H. habilis is indistinct from A. africanus
Robinson (1965)
• H. habilis diagnostic features insignificant …
– Bed I = A. africanus
– Bed II = early H. erectus
H. sapiens
Leakey (1966)
• H. habilis direct ancestor
to H. sapiens -- descended
from A. africanus. H. erectus
a dead end.
H. erectus
H. habilis
A. africanus