This article is about scientists who traced a man from South Carolina's Y chromosome to a lineage older than the oldest anatomically modern human fossils. This suggests that the Y chromosome predates modern humans by an estimated 70%. The man's Y chromosome was found to be extremely unique, being similar only to a small population in sub-Saharan Africa. Scientists also matched the Y chromosome variation to 11 other individuals, but as each chromosome differed considerable, they conclude that humans did not descend from one "grandfather". Rather, they believe that individual pockets of genetically isolated populations preserve our genetic diversity. They are confident that future discoveries will increase the age of the Y chromosome tree.
NOS Themes:
1. Role of chance - It was completely by chance that scientists came across this man's unique Y chromosome.
2. Conflicts within the scientific community - The scientists in this study refute the belief that humans descended from one "grandfather" human, but rather from different populations of diverse genetics.
3. Role of motivation and curiosity - Curiosity is what motivates people to get their DNA analyzed. Curiosity is what ultimately led to these scientists' discovery in this man's genetics.
It would be even better now to conduct a further test and to see if that same chromosome would be found in chimps and apes since we descended from them. Also it would be nice for science to clearly distinguish the line between where you are an ape, and where you are considered human. This article talks about it in more depth.
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