Baffling 400,000-Year-Old Clue to Human Origins

The article “Baffling 400,000-Year-Old Clue to Human Origins” by Carl Zimmer, talks about how a fossil, a thigh bone, could lead to new discoveries on evolution. In Spain in a cave called Sima de los Huesos (“the pit of bones”), a 400,000 year old femur was found. By testing the extracting DNA, scientists were able to test to see whether the DNA would match that of the Neanderthals. Unexpectedly I didn’t match, but rather was closely related to the DNA belonging Denisovans, which had been discovered in Siberia in 2010. This group is thought to be limited to East Asia, and they are also not thought to look like the Neanderthals. Based on this new discovery, scientists believe that humans, Neanderthals and Denisovans all shared a common ancestor from a half a million years ago. It is believed that these ancestors split off, with Humans staying in Africa, Neanderthals heading west and Denisovans moving eastward. Many scientists also believe that humans interbreed with the Neanderthals and Denisovans, later causing these two groups to become extinct.   Scientists have come up with many explanations. One explanation stated that the humans of the Sima de los Huesos weren’t really Neanderthals but belonged to ancestors of Neanderthals and Denisovans. Another says that this new DNA was passed to the Neanderthals and Denisovans disappearing from Neanderthals and becoming replaced by alternative forms (variants.) The most radical theory is that the humans in that region belong to a different branch of humans, a species called Hom erectus, from 1.8 million years ago. Although this new discovery shed light on newfound information, it has also raised lots of questions.

This discovery may not be important to humans today, but we can get a better look at evolution. This discovery is really astounding at how far back this DNA was found, it is 300,000 years older than the previously oldest DNA. This finding rises many questions that many scientists will know be on the hunt to find about the Denisovans. I think that this discovery is important to finding more clues to our ancient past and clues to finding the whole story of evolution. There are some pieces that we know, but so many things are still currently unknown.

I thought that this article was very informative and included lots of information from different scientists and colleges who had information on this topic. There was also a lot of background information which helped to better understand where is was taking place. I thought that the author could have done a better job organizing the article because it wasn’t in a very neat order. I thought that it talked about the discovery and then talked about some background and then about future things and it got very confusing. It would have been easier to read if everything had been in a chronological order. Overall, I found this article very interesting, and I think that this will be very important in both science and history.

Zimmer, Carl. "Baffling 400,000-Year-Old Clue to Human Origins." Nytimes.com. N.p., 4 Dec. 2013. Web. 4 Dec. 2013. <http://www.nytimes.com/2013/12/05/science/at-400000-years-oldest-human-dna-yet-found-raises-new-mysteries.html?ref=science&_r=0>.
http://www.nytimes.com/2013/12/05/science/at-400000-years-oldest-human-dna-yet-found-raises-new-mysteries.html?ref=science&_r=0