On the day that I am writing this, I observed TV clips of the new show of Cerque du Soleil, entitled Totem. According to the on line program description it is a performance “which traces the journey of the human species from its original amphibian state to its ultimate desire to fly”. It brought me to the most important question in genetics; what is the origin of modern humans. It’s a complex question without a conclusion. The studies are divided into so-called models, each based on varying degrees of empirical data, but, each being, substantially, theoretical.
There is the Replacement Model which relies on mutations and leaves some important DNA
The Regional Continuity Model is based on change, but, points to some anatomical traits going back 100,000 years with human development somewhat restricted by the concept of regional species; African, Asian, etc. There is some speculation that natural selection may have had a hand in allowing those with traits such as stronger immune systems to survive as being the fittest within the group.
My favorite, however, is the Assimilation Model, advanced by Gunter Brauer of the University of Hamburg in Germany because it is the most interesting and also because it provides the most grist for the writing mill. It is based on the premise that Homo sapiens and Neandertal, likely descendants of a common species called Homo heidelbergensis, were actually contemporaries. Adding to this hypothesis was the discovery, in 2003, of a partial skeleton of a male Homo sapiens teenager, dating back approximately 30,000 years and having a mix of old and new anatomical features suggesting interbreeding. Is it possible that such a hybrid is the distant ancestor of who and what we are today?
Using the Assimilation Model makes for some interesting speculation. It is a fact that Cro Magnon had a larger brain than Neandertal and somewhat larger than we do. So, if a hybrid species came to be, could this have resulted not in the evolution of the human brain but, rather its devolution. Could war, violence, deception and other negative traits exhibited by modern man be our primitive side exposing itself. Reflect on the possibility that when we see someone exhibiting brutish or anti-social behavior and comment that they are acting like a Neandertal, there might very well be some truth in that observation.