He illustrates his stand with the examples of the theories surrounding the evolution of man by starting with the rather shocking theory that we all as humans originate from the continent of Africa
This topic is very important to biological and physical anthropology because it explains why we are all so different racially and genetically and seeks to explain with the help of many theories whether Darwin's theory is actually right in saying that as humans we have only recently evolved from apes. He compares the "originate in Africa thesis" with the "out of Africa thesis" where he is trying to explain the origin of our genetics and evolution.
The author uses the technique of taking up many hypotheses and theories and assessing their truth and in the end he gives his verdict in the favour of the theory given by Darwin, the Out of Africa hypothesis.
" This theory maintains that modern humans evolved in Africa and then spread around the world. Boiled down to its essence, the hypothesis states that modern humans are both relatively recent (100,000 to 200,000 years old) and African in origin. A major prediction of this hypothesis is that the earliest remains of modern humans will be found in Africa, dated to an appropriate time period."
The author goes on to discuss the " Multiregional hypothesis" which he argues depicts that we as modern humans evolved from different locations and hence our racial and genetic differences. According to this school of thought
"these regional populations evolved along parallel paths and reached modernity at roughly the same time. Because the populations were largely isolated from one another, they developed distinctive regional features, which people recognize today as "racial" differences." ( Multiregionalists believe that Neandertals, originate from the European continent.)
He then goes on to say how there are three different recent researches go in the favour of the Darwinian view and oppose the Multiregionalists view which he addresses one by one as:
The east african population has been found to be so diverse that the genetic composition of the population" shows that these lineages are very diverse and
humans did evolve from these areas.Most of the worlds oldest lineages were found there d 170,000 years ago.
Secondly because of the discovery of the "African Herto skullsthe Herto specimens (are) the earliest modern Homo sapiens yet found-direct ancestors of people living today."
He concludes that the Neandertals' DNA was not closer to that of the modern Europeans. "The work was a strong blow to the theory that humans evolved in several places simultaneously. "Neandertals cannot represent a regional European transition from Homo erectus to modern Homo sapiens"
4. Did the author address any contrary evidence or the opinions/work of others that run counter the author(s) claims
Although he devotes his entire discussion to proving the multiregionalists wrong he does refer to the possibility of " mtDNA contamination from researchers or others who have handled the fossils" but he is quick to provide evidence to suggest otherwise. He does give the multiregional theory its fair share of discussion though..
5. What were the strengths and/or weaknesses of the author(s) argument