John Hawks, an archaeology professor at UW-Madison, has been very influential in the study of how humans relate to neanderthals, whose existence overlapped with our human ancestors. Are we part neanderthal? The answer is a surprising yes.
By comparing nucleotide base pairs from in tact chromosomes found in neanderthal fossils to the nucleotide base pairs in our own chromosomes, it has been found that about 3% of our DNA is similar to that of neanderthals. This process is like that discussed in Rick Kittles’s presentation- scientists were able to trace some nucleotide base pair sequences in modern humans to those found in neanderthals, finding what is equivalent to a 3% relativity in human (although Africans share less than 3%) and neanderthal genetics. Today, Asians share the most similar DNA patterns with neanderthals.
Because humans share some genes with the neanderthals, this means that there was mating between the two groups. We learned that a way to tell if two groups of organisms are two different species was to see if they produced viable, fertile offspring. Since neanderthals and homo sapiens were able to do this, these two groups must not have been two different species originally.
But how did they become separate species? I thought it had to do with the establishment of neanderthals in Europe and homo sapiens in Africa. This geographic isolation prevented any further flow of DNA between neanderthals and homo sapiens (allopatric speciation), therefore preventing the creation of a species combining the genes of both groups. If a combination species had occurred, we would have kept much more than 3% of neanderthal genes from the past 100,000 years. However, neanderthals later died out, causing any more gene flow between the homo sapiens and neanderthals to forever cease.
But how did neanderthals die out? Common beliefs in the past were that neanderthals were much less intelligent than homo sapiens. However, this was not the case- they were really less adapted to their environments than homo sapiens. Their intelligence was shown shown through the discovery of tools and weapons found near the bones of neanderthals. There is also evidence that they had their own form of communication.
Thanks to this presentation, I got a glimpse into the genes that make up my past and discovered that everyone carries a little bit of the past with them in the form of genes shared with ancient neanderthals.