homo-sapiens in Africa, the modern humans migrated out to all other parts of the world with
some leaving behind to live. These modern human populations took over the regions that they
migrated to from the local populations of homo-erectus which were more or less extinct by that
time.
Of the two evolution models above, there are reasons probably to favor the replacement model
over the multi-regional model. Why the replacement model? Firstly, one reason would be that the
earliest bones and fossils of modern humans were found in Africa. These fossils are believed to
be around 130,000 years ago. It might the time around which the first modern humans appeared.
They represent the oldest fossils of modern humans to be found, much older to other fossils or
bones found in any other parts of the world.
The study of genetic structure of modern human populations also suggests that modern humans
have a commonness, close to each other, in other words minimal diversity in genes. This is more
consistent with the replacement hypothesis. From the genetic studies, it is shown that the genetic
makeup of Africans is more distinctive to other races of humans. The other races of modern
humans are more or less similar in the genetic structure to each other. This might suggests that
modern humans come from a common genetic heritage which was originated in Africa, then
evolved genetically into the other races.
The study of Neanderthals also showed some evidence of human evolution by replacement
model. Neanderthals were a separate species which evolved from homo-erectus populations and
generally lived in Europe. Some people suggested that Neanderthals might have evolved into
modern humans in Europe thus proving the multi-regional theory. However, studies in genetic
makeup of the Neanderthals’ fossils and bones showed vast distinctive differences and features
from modern humans. There was no genetic flow between the two which means that they could
not have belong to the same species more or less. It suggests the Neanderthals’ line of evolution
was far removed from that of modern humans and for a very long time. The physical
characteristics and features found in Neanderthals showed little to no evidence that supports the
physical functions and abilities of modern humans with their own features. This shows that
Neanderthals could not have evolved into homo-sapiens but rather were extinct and taken over by
modern humans.
Another evidence that shows modern humans could not have evolved from Neanderthals is in the
archeological remains of the two. The tools used by the Neanderthals were more simple and
primitive compared to the modern humans. They had significantly lesser types of tools to help
them with their chores. The tools of modern humans showed evidence of their complexity in the
way of thinking and work over the Neanderthals. Tools of late Neanderthals also showed signs of
influence by early modern humans who might have co-existed with them at the time Neanderthals
were thinning out of existence. Remains of Neanderthals settlements found evidence that they
lived in small and less complex communities which kept to themselves. This could have led to
isolation and their eventual extinction. The early modern humans, on the other hand, lived in
bigger settlements over a wider spread area and showed signs of trading between other human
populations even in far off regions. The absence of art culture in Neanderthals throughout their
timeline suggested that they did not have the tools and abilities to evolve in into modern humans
who could draw pictures and paintings on walls, rocks and even on their tools. These showed all
the more that Neanderthals were really a separate species or race which died off rather than
evolved into modern humans.
Therefore, based on the above evidences and reasons, the “Out of Africa” hypothesis seems to be
more favorable in the evolution of the modern human. However, it may not necessary be accurate
as human evolution may be more complex than we might think. By just using either hypothesis –
multi-regional or replacement, we cannot hope to understand or describe the ancestral roots or
origins of humankind. There are more variables than these in the appearance of the first modern
human and they must also be explored to give adequate insights to the heritage of the human
species.
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