The earliest dispersal of the genus
Homo: Homo erectus and
contemporaries
Oct. 14, 2008
Introduction
• The Pleistocene
– Early (or Lower) 1.8 - 0.78 Mya
– Middle - 0.78 - 0.125
– Late (or Upper) - 0.125 - 0.01
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~ 2 Mya hominins disperse outside Africa
Widely distributed in space and time
Morphological variation in geographical groups
All hominins outside Africa belong to the genus
Homo
Many generic names prior to Modern
Evolutionary Synthesis
Africanthropus, Anthropus, Archanthropus,
Atlanthroprus, Cyphanthropus, Euranthropus,
Hemianthropus, Palaeanthropus, Palaeoanthropus,
Pithecanthropus, Praehomo, Protanthropus,
Pseudohomo, Maueranthropus, Meganthropus,
Nipponanthropus, Notoanthropus & Sinanthropus =
Homo
A new kind of hominid
• Discoveries of Homo erectus began in the late 19th century,
e.g. E. Dubois in Java (Pithecanthropus); then later in the early
20th century in China (Sinanthropus).
• Homo erectus in East Africa by 1.8 Mya
• Homo erectus (Asia) or Homo ergaster (Africa)
• Grade - A grouping of organisms sharing a similar adaptive
pattern. It is not necessarily based on closeness of evolutionary
relationship, but does contrast organisms in a useful way.
• Clade - A monophyletic grouping of organisms that all share
a common ancestor.
• Adaptive shift (including diet, body size and habitat) has taken
place.
Morphology of Homo erectus
• Brain size – Range750 to 1,250 cc (900 average)
• Body size – limb proportions like that of modern
humans but skeletal-muscular features are more
robust
• Cranial shape – thick cranial bones, large browridge,
projecting nuchal torus, sagittal keeling, broad cranial
base
• Dentition – similar to modern humans but posterior
teeth larger
East Africa
• Olduvai, Tanzania – OH 9, 1.4 Mya
• East Turkana, Kenya – KNM-ER 3733, 1.8
Mya
• West Turkana, Kenya – KNM-WT 15000, 1.6
Mya
• Bouri, Ethiopia – Cranium displays features of
Homo erectus fossils from Africa and East
Asia, 1 Mya
• Bouri Skull from
Ethiopia, ~1 Myr
Nariokotome or Turkana Boy
• KNM-WT 15000
Who were the Earliest African Emigrants?
• Dmanisi, Georgia
– ~ 1.75 Mya
• Why disperse
from Africa?
- Traveling with
food source?
- Increase in
population size
led to the need for
more space and
resources?
Dmanisi Hominins
• Oldest and best preserved
hominin fossils found
outside Africa; 1.75 Mya.
• Low braincase, wide base,
brain size 650-780 cc,
thickening along sagittal
midline
• Less robust, short stature
thinner browridge,
projecting lower face, large
upper canine
• Many stone tools, Oldowan
or Mode 1
Historical overview of Homo erectus
discoveries
• Distributed across Africa and Eurasia
• ~ 1.8 Mya to as late as 50,000-25,000 in Pacific
Southeast Asia
• Java – along the Solo river near Trinil Dutch
anatomist Dubois found a skullcap and later a femur
in 1891. Other important sites - Sangiran and
Ngandong
• Peking (Beijing) – at Zhoukoudian (Middle
Pleistocene, ~400 Ka) many fossil specimens (cranial
and postcranial) and stone tools studied by Black and
Weidenreich in the 1920s and 1930s
Homo erectus from Indonesia
Sangiran 17
NG 6
Perhaps surviving in Southeast Asia until as
recently as 25-50 Ka?
Homo erectus from China
Cultural remains at Zhoukoudian
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Fire?
Hunting? Or scavenging? probably both
Many stone tools
Cannibalism?
Hunters or the Hunted?
Other Chinese sites
• Lantian 650 Ka
• Yunxian 350 Ka
• Hexian 1.15 Ma
Summary of East African Homo
erectus/ergaster
• African Homo erectus fossils aren’t as robust
as East Asian Homo erectus
• One or more species?
• Considerable variation in size and
morphological features, both cranial and
postcranial
North Africa and Europe
• Algeria 700 Ka and
Morocco 500 Ka
• Ceprano, Italy 800-900
Ka
Technological and population trends in
Homo erectus
• Technological trends – 1.4 Mya Acheulian or
Mode 2 replaces the Oldowan or Mode 1
• Population trends – increase in group and
population size coupled with wider
geographical distribution
Oldowan
Acheulian
Interpretations of Homo erectus:
Continuing uncertainties
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One or more species?
Grade or Clade?
What preceded early Homo?
Ancestor of modern humans?
Cognitive developments?
Why emigrate from Africa?
How many dispersals and how many species?
Stw53
KNM-ER 1813
Hunting or scavenging?
Probably both.