Fossils
recovered in Sima de los Huesos, Spain contain new DNA of the Neandertal
genome. In addition, this discovery of the new DNA places Neandertals living in
Europe approximately 430,000 years ago. The DNA was discovered in a tooth and
leg bone. Furthermore, the DNA recovered from the tooth and leg bone only match
1% of the existing genome of Neandertals. Therefore, the DNA recovered was used
to compare a women Neandertal’s DNA and a Denisovan (believed to be a distant
cousin of Neandertals and Homo sapiens) women’s DNA. Homo heidelbergensis is believed to be the
common ancestor of both Homo sapiens and Neandertals, so Denisovan DNA could be
a missing link in human evolution. This comparison is vital because its results
will help scientists discover the genetics of human evolution.
After the comparison, a greater
genetic mystery emerged. Since, the nuclear DNA (inherited from both parents to
the child) matches Neandertal DNA. However, the mitochondrial DNA (inherited
usually only from the mother) matches the Denisovan DNA. This suggests that a genetic split or
divergence occurred approximately 430,000 years between Neandertals and
Denisovans. Furthermore, the new genetic data implies that genetic split
between Neandertals and Homo sapiens occurred even sooner, approximately
650,000 years ago. However, the new genetic evidence does not prove or disprove
that Homo heidelbergensis is a common ancestor of the three species. As the
most likely explanation for the difference in DNA is inbreeding among the
different species.
Original Source: https://www.sciencenews.org/article/ancient-dna-reveals-who-spain%E2%80%99s-%E2%80%98pit-bones%E2%80%99-cave?mode=topic&context=87&tgt=nr
Additional Readings: http://www.nytimes.com/2016/02/23/science/ancient-humans-may-have-left-a-genetic-mark-on-neanderthals.html?_r=0
No comments:
Post a Comment