Recent studies are reversing previous ideas about the relationship between Neanderthal man and Homo sapiens.
Neanderthal
man is believed to have evolved around 300,000 years ago, and was a descendent
of early hominids that moved out of Africa around 500,000 years before this.
Modern humans, on the other hand, are thought to have appeared only around 100,000
years ago after a second wave of migration from Africa occurred.
Until
recently, scientists were of the view that although both groups co-existed for
around 40,000 years, they did not interbreed and were separate species. This
assumption was originally based on skeletal comparisons, but studies of
mitochondrial DNA by Svante Pääbo at the University of Leipzig in 1997 also
appeared to confirm that the differences between Neanderthals and humans was
too great for them to belong to the same species.
Early
Portrayals of Neanderthal Man
Fossil
bones of Neanderthal man were first discovered in Germany in 1856, although
earlier remains found in Belgium and Gibraltar may also have been Neanderthal.
Based on reconstructions using these and similar bones, anthropologists
initially concluded Neanderthals were shorter and stockier than modern man,
with heavy brow ridges, weak chins, a protrusion known as the ‘occipital bun’
at the base of the skull and a larger cranial capacity.
The
French palaeontologist, Marcellin Boule, reinforced this view by promoting
Neanderthals as slow -witted, hunched over and ape-like . Phrenologists at the
time explained away the larger cranial capacity by saying that the extra
frontal skull volume in Neanderthals did not equate with additional
intelligence.
Based
on these features, and averages taken from bone measurements of both Neanderthals
and humans, scientists originally proposed that Neanderthals were a different
species to humans. The renowned anthropologist Rudolf Virchow, however,
maintained that the fossils found of Neanderthals were simply the remains of
humans displaying symptoms of arthritis and rickets.
Recently
Revised Views: Neanderthals Had Human Qualities
These
claims, and others that suggested early drawings of Neanderthals were
‘political reconstructions’ which depicted them as more ape-like than they
should have been, led to a reassessment of this group of hominids in the 1970s.
The result was that Neanderthals gained a new classification: Homo sapiens
neanderthalensis.This implied they were in fact a closely related sub species
of Homo sapiens.
Additional
evidence also points to this assumption – Neanderthals, mostly discovered in
northern European regions, were clearly sophisticated enough to be able to cope
with harsh winters, and displayed human qualities such as burying their dead
and participating in symbolic rituals.
They
also used tools, fire and made necklaces. Furthermore, several of the 400 or so
Neanderthals that have been unearthed have displayed symptoms of severe
arthritis and other crippling diseases, suggesting they were cared for by other
members of their group. The remains of an old, arthritic male found in France
in 1908 had no teeth at all, and would have needed to have his food processed
for him before he could eat anything.
Neanderthals
May Have Been Capable of Speech
The
discovery of a Neanderthal hyoid bone in Israel that closely resembles those
found in modern humans has led some researchers to believe Neanderthals were
capable of speech. The hyoid bone supports the tongue and allows speech to
occur when working in conjunction with the larynx. This find offers further
support to the view that Neanderthals were closely related to us.
Moreover, Pääbo
made further studies of nuclear DNA from Neanderthals in 2010, and this time
found that up to 4% of modern human DNA is identical to Neanderthal DNA. This
supports the theory that the two groups did interbreed with each other.
Humans May
Have Interbred With Neanderthals in the Middle East
As
a part of this research, Pääbo examined variable gene sequences in French,
Asian and New Guinean populations and compared them to Neanderthal DNA. He
found similarities between these and the same DNA regions in Neanderthals.
The fact that
these variable regions are not present in Africans suggests that interbreeding
with Neanderthals occurred after the second wave of migration of humans out of
Africa. Pääbo and other researchers believe this may have occurred around
40,000 to 80,000 years ago in the Middle East, before further migrations
occurred.
At any rate,
it does appear feasible that humans and Neanderthals were indeed members of the
one species, as interbreeding would have had to occur to produce such
similarities in their DNA. Further research should help to confirm or reject this
view.
Sources
• O’Neill, Dennis, 2010,
"Neandertals," Palomar College California, palomar.edu
• Shermer,
Michael, 2010, "Our Neandertal Brethren: Why They Were Not a
Separate Species", scientificamerican.com
• Wilford,
J., 1999, "Discovery suggests Humans Are a Bit Neanderthal,"
University of California, cogweb.ucla.edu
•
Wong, K., 2010, "Neandertal Genome Study Reveals That We Have a Little
Caveman in Us", scientificamerican.com
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