This assignment will discuss The assimilation model, modern human origins in Europe, and the
extinction of Neandertals by Fred
H. Smith, Ivor Janković and Ivor Karavanić
and review what these authors conclude was the
fate of Neandertals and how they reached those conclusions.
Current research suggests
that modern humans evolved from archaic humans (most commonly Neandertals) starting
in Africa over 200,000 years ago (Feder, 2014) Fossil remains of anatomically
modern Homo sapiens have been found throughout Europe and Asia (Feder, 2014)
Neandertals existed between 30,000 and 300,000 years ago. When the first Neandertal
skeletal remains were recognised as not being Homo sapiens in 1846 it caused
quite a debate in the archaeological community.
Views were varied, Smith, Jankovic & Karavanic (2005), discuss
briefly three main views. Some thought it was a deformed specimen of an early
homo sapien (Rudolf Virchow, 1872 in Smith et al, P1). Others that it was a
descendant of an archaic Aboriginal race (Smith et al. 2005). The third view at
the time was that this was a new species because it was so distinctive to early
Homo sapiens. William King named the
species homo Neandertal (Smith et al,2005). Smith Et al, 2005 review the theory that
Neandertals were separate from Homo sapiens.
Through the study of fossils
and more recent studies of ancient DNA archaeologists are able to tell that Neandertals
are not direct ancestors of modern humans but a side branch (Feder, 2014,:
Smith et al, 2005: Straus, 2005). Various dating methods such as radio carbon
dating, thermouminesence and electron spin resonance tell us that neandertals and
early or anatomically modern Homo sapiens existed at the same time (Feder, 2014,:
Smith et al, 2005: Straus, 2005). Fossil
evidence tells us that Neandertals and anatomically modern Homo sapiens lived
around Europe and Asia during the same time periods (Feder, 2014,: Smith et al,
2005: Straus, 2005). Evidence suggests
that Neanderthals were not as unintelligent as first thought they were adapt at
making tools and overcoming the cold and that they possibly did not die out
through a biological event (smith et al, 2005).
The differences between
Nenadertals and anatomically modern humans are many both in physical and
cultural ways. Neandertals had thicker
bones, broad face and a sloping forehead, they had a more robust chest, and
fossil evidence suggests they suffered more trauma resulting in broken bones
and even death. (Smith et al, Feder,
2014). Culturally Neanderthals seemed to have basic control of fire, the ability
to make and use basic tools and more complex hunting strategies than earlier
Homo species. There is little evidence of art work and adornment however it has
been found in some Neanderthal fossil sites. There is evidence that Neanderthals
buried their dead (Feder, 2014 Australian museum, 2014).
Homo sapiens had a smaller
bone structure, the evidence suggests they had a more complex control of fire
and used hearths as well as using fire for warmth. They had more complex
hunting methods they had to develop as they were not as strong as Neanderthals
they made and used much more complex tools and there is evidence to show they
wore animal skin clothing and with their use of fire survived longer in colder
climates than Neanderthals. They used more adornments there is evidence of more
‘cave art’ (Feder, 2014)
Smith et al (2005), describe
Bunning as a prominent or bludging occipital at the back of the skull, this was
prominent in neanderatals although they have much flatter foreheads, this
occipital bun is not found in early anatomically modern homo sapiens fossils
found in Africa however it is found in later fossils around Europe. Smith et al
(2005) give three reasons for this, firstly Bunning in Europeans could be part
of evolution, secondly the Bunning in both European anatomically modern Homo
sapiens and neandertals could be a result of a common ancestor and lastly it
could be the result of interbreeding.
Smith et al conclude the more likely explanation is a result of mixing
the gene pool.
Even with the differences in
morphology and DNA there have been some fossil sites where Neanderthals have
exhibited more homo sapien like appearance and Homo sapiens seem to have
Neanderthal appearance. there are modern features in later Neanderthal
populations (Australian Museum 2014)There has been research on comparing the
DNA of Neanderthals and homo sapiens it has been found that early homo sapiens fossils
in Europe and Asia contain 1- 4% of Neanderthal DNA (Australian Museum, 2014). Although they share no DNA with Homo sapiens
from Africa so it seems that Neanderthals and Homo sapiens did not interbreed
frequently and only in areas where they lived in close proximity for thousands
of years, for example the Vindija Neanderthals look more modern than other
Neanderthals, which suggest that they may have interbred with incoming Homo
sapiens (Freder, 2014; Smith et al, 2005) There are some modern Europeans that
have a similar jaw line to Neanderthal fossils. “European
Neandertals have a high frequency of occipital buns, a distinctively shaped
posterior vault characterized by paralambdoidal flattening and a distinct shelf
below the nuchal torus.” (Smith et al, 20 P4) Although all the evidence must be considered
together there is a good chance that it could mean that interbreeding caused
this same feature in Homo sapiens Fossil sites have shown that
Neandertals used tools made by Homo sapiens.
Fossil sites have also shown a mixture of Neanderthal objects and homo
sapien objects. More convincing has been
the discovery of a Neanderthal / homo sapien hybrid (Freder, 2014).
As Homo sapiens spread and
came into contact with Neandertals, Three different
models explain what may have occurred. Smith et al (2005) propose the
assimilation model in which there was an exchange of genetic material. In other
words interbreeding occurred and neandertals faded out of existence. It is
believed that when Homo sapiens left Africa and spread out across the world as
they came across other archaic populations interbreeding occurred. This could
have been made easier by the lower numbers of Neanderthal reproductive success
and survival rates, as well as the relatively early age of death around 30
years although some fossils have been found with an age of 40 years.
(Australian museum, smith et al)
“The
Assimilation Model argues that yes, modern humans do come out of Africa, but as
they move into these areas
where Neandertals live – like western Asia and Europe – the population dynamics
of their interaction are very complex, and some Neandertal elements are
assimilated into the ultimately larger, human gene pool.” (Smith, F mediarelations.illinoisstate.edu/report/1213/oct2/neandertal.asp)
Multiregional evolution
explains that the human species first arose around two million years ago and
subsequent human evolution has been within a single,
continuous human species. In
other words Neandertals evolved into Homo sapiens this species encompasses all archaic human
forms such as Homo Erectus and Neanderthals as
well as modern forms (Encyclopaedia Britannia, Stringer, 1990).Traits found in earlier
homo specimens can be seen in modern day humans (Encyclopaedia Britannia, Smith
et al, 2005).
Recent African model or out
of Africa model states that early humans evolved in Africa around 200,000 –
600,000 years ago and one branch left Africa around 125000 and 600000 years ago
and overtime replaced early human populations including Homo erectus and Homo
Neanderthals (smith et al, 2005).
It is speculated that the
exchange of genetic material was incidental, Feder (2014) speculates that the
two cultures would have prohibited a free exchange of partners and that it
would have been quite unusual for the two species to mix although there seems
to be a conflicting view on this – interbreeding would have occurred rarely but
often enough for assimilation to have occurred and Neanderthal DNA to be
evident on early and modern homo sapiens (Smith et al, 2005).
Smith et al conclude that
due to the extensive numbers of Homo sapiens and interbreeding with
Neanderthals it is entirely possible Neanderthals assimilated with Homo sapiens
populations and did not die out from a biological event. Smith et al (2005)
prefer the assimilation model (as an explanation as opposed to the regional
model and recent African model (replacement of Neanderthals). The features of
Neanderthal’s were most likely covered by the Homo sapiens DNA after a few
thousand years (Smith et al, 2005).
Reference
List
Encyclopaedia Britannica ©2014 Encyclopedia
Britannica, Inc.
Feder, K.L. (2014). The Past
in Perspective: An Introduction to Human Prehistory. (6th
ed).New York: Oxford University Press.
Relethford, J 1998, ‘Genetics of modern
human origins and diversity’, Annual Review of Anthropology,
vol. 27, pp. 1–23.
Smith, F, Jancovik, I & Karavanić, I 2005, ‘The assimilation
model, modern human origins in Europe, and the extinction of Neandertals’, Quaternary
International, vol. 137, no. 1, pp. 7–19.
Straus, L On the
Demise of the Neandertals quaternary International, July 2005, Pages 1-5
Stringer, CB 1990, 'The emergence of modern humans', Scientific
American, vol. 263, pp. 98-104.
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