Chapter 4
Homo neanderthalensis – 400 000 onwards – Europe / western Asia
Early Neanderthals: 150 000 ya
Classic Neanderthals: Eurasia 70 000 ya
Homo sapiens – Africa
250 – 125 000 ya > fossils with transitional traits (primitive and modern)
100 000 ya > dispersal of anatomically modern H. sapiens > bottleneck followed
Last shared common ancestor > Homo heidelbergensis – 600 – 500 000 ya
40 000 ya; another dispersal of modern humans from Africa and western Asia > Australia,
Siberia Europe same time development of modern behavior in Africa & transition to late
stone age, in Europe transition to upper Paleolithic.
Hypotheses for origin of Homo sapiens;
- Multi region hypothesis; evolved in several regions (in the old world) arise gradually
from Homo erectus populations regional continuity in populations
- Out of Africa hypothesis; single center of origin, absolute replacement of older forms of
Homo by Homo sapiens. Earliest fossils of Homo sapiens must be found in Africa.
- Hybridization and replacement model; evolution in Africa and Europe, slow expansions out
of Africa of emerging modern humans + varying degrees of genetic mixing.
-assimilation model; emergent Homo sapiens population from Africa would have effected
evolutionary processes in other regions> assimilating regional early human groups into the
modern human gene pool
Multiple dispersals out of Africa
Africa played the primary role in modern human origins
Anatomy of Homo sapiens;
- Skull shape (chin, vertical forehead, cranial capacity, table 2)
- Limb bones are long relative to the trunk
- Distal limb segments are long relative to the overall limb
Fossils in three chronological groups
1) > 250 000 ya Homo sapiens/ergaster traits evident
Heidelbergensis/leakeyi/rhodensiensis/ archaic Homo sapiens
2) 250 - 125 000 ya transitional group, primitive and modern traits
Homo helmei/Homo sapiens
3) < 125 000 ya clear anatomically modern humans
Homo neanderthalensis – 400 000 onwards – Europe / western Asia
Early Neanderthals: 150 000 ya
Classic Neanderthals: Eurasia 70 000 ya
Homo sapiens – Africa
250 – 125 000 ya > fossils with transitional traits (primitive and modern)
100 000 ya > dispersal of anatomically modern H. sapiens > bottleneck followed
Last shared common ancestor > Homo heidelbergensis – 600 – 500 000 ya
40 000 ya; another dispersal of modern humans from Africa and western Asia > Australia,
Siberia Europe same time development of modern behavior in Africa & transition to late
stone age, in Europe transition to upper Paleolithic.
Hypotheses for origin of Homo sapiens;
- Multi region hypothesis; evolved in several regions (in the old world) arise gradually
from Homo erectus populations regional continuity in populations
- Out of Africa hypothesis; single center of origin, absolute replacement of older forms of
Homo by Homo sapiens. Earliest fossils of Homo sapiens must be found in Africa.
- Hybridization and replacement model; evolution in Africa and Europe, slow expansions out
of Africa of emerging modern humans + varying degrees of genetic mixing.
-assimilation model; emergent Homo sapiens population from Africa would have effected
evolutionary processes in other regions> assimilating regional early human groups into the
modern human gene pool
Multiple dispersals out of Africa
Africa played the primary role in modern human origins
Anatomy of Homo sapiens;
- Skull shape (chin, vertical forehead, cranial capacity, table 2)
- Limb bones are long relative to the trunk
- Distal limb segments are long relative to the overall limb
Fossils in three chronological groups
1) > 250 000 ya Homo sapiens/ergaster traits evident
Heidelbergensis/leakeyi/rhodensiensis/ archaic Homo sapiens
2) 250 - 125 000 ya transitional group, primitive and modern traits
Homo helmei/Homo sapiens
3) < 125 000 ya clear anatomically modern humans
