The latest study aimed at answering this question suggests the latter – when Neanderthal man met Homo sapiens woman it resulted in what scientists euphemistically call "gene flow". It seems that this interbreeding, which probably took place somewhere in the Middle East when the first modern humans migrated out of Africa, has resulted in a little bit of Neanderthal in all of us today with a non-African ancestry.The story also shows how hard it can be do science:
This enabled them to compare the Neanderthal genome with that of five modern-day people from around the world, and, to Paabo's astonishment, Neanderthal DNA sequences were found in the genomes of the three people who lived outside Africa. Paabo freely admits that he was biased against such a finding. His earlier work on mitochondrial DNA suggested no such interbreeding between Neanderthals and modern humans, so his initial reaction was that the data had to be a statistical fluke, or erroneous.This shows two things:
But it is a measure of greatness in science if you can accept something that you had previously rejected, when faced with new and convincing evidence.
Comparisons between the genomes of modern humans and the Neanderthals clearly indicated that there was a small but significant amount of interbreeding early in the evolutionary history of Homo sapiens, most probably after our species had first emerged from Africa between about 80,000 and 50,000 years ago. Other scientists, such as Professor Joao Zilhao of Bristol University, who has long argued that there was close cultural and biological interaction between Neanderthals and modern humans, can rightly feel vindicated for their somewhat unfashionable stance.
1. it shows how science can and should be done. New information should always be incorporated into the existing framework of a particular discipline. On one side of the fence, there is the perspective that Neandertals were replaced by early modern humans that came from North Africa. On the other side is the idea that Neandertals interbred with the incoming moderns and that the modern Europeans are a result of this hybridization. Maybe the answer lies somewhere in between. As Jan Simek once put it, maybe there was hybridization here in this valley but replacement two valleys over. It is becoming increasingly clear that the transition to modern humans was neither simple nor quick.
2. it shows how stark the contrast between conventional science and young earth creationism really is. For YECs, there are no new ideas or hypothetical constructs to be tested. Data that does not fit the model must be shoehorned, twisted or distorted to fit or else be ignored, as much data is. The ability to take a favored concept or theory and rethink it based on new ideas or new information is the hallmark of science, not creationism.
This new finding shows how science progresses and how only by adding the new information to the mix will we ever be able to understand the transition to modern humans. As such, it enriches our understanding of modern human ancestry in particular and the universe in general.
Now playing: Pat Metheny Group - The Way Up: Part Three