According to a report by ScienceNow Neanderthals may not have the same features that that they normally possess in display cases in museums around the world. This new hypothesis was brought about using new DNA evidence from two female Neanderthals originally from Croatia. The new evidence shows that they may have sported darker skin tones and even had brown eyes. Also with this new information they should be able to reveal new data on how the prehistoric family that includes Neanderthals but also modern humans has evolved over time, which also died out about 30,000 years ago.
With this new information skeptics are numerous. Alot of outside researchers have voiced their opinion on the matter saying things like breaking the long held hypothesis that Neanderthals have had lighter skin for the sole purpose of gaining the required amount of Vitamin D. Even with the numerous problems that have been discovered scientists have seen a silver lining because its logical that Neanderthals from different regions would have different levels of pigmentation in skin tone. To determine this the researchers focused on 40 different stretches of genetic material. The specific areas that they were looking at were ones used to determine the pigmentation of living people. The main problem with this is that hair color is controlled by multiple genes. To solve this problem researchers used a technique in which they added up each gene and which ever gene was in the majority would be the one displayed by the organism. For example a female Neanderthal known as Vi33.26 had 3 genes for blue eyes, 4 genes for not blue eyes, and one gene for not brown eyes, and finally 7 genes for brown eyes. This gave a positive number count for brown eyes and a negative number count for blue eyes. Most likely giving Vi33.26 brown eyes.
This technique was validated by testing it with 11 people and had a 60% success rate. They accept that low rate due to the massive amount of complexity in hair color and eye color. Another problem with the data is that hair color and eye color markers used are based on modern human genetic variation. When Neanderthal eye and hair color genes are unique to them.
Scientists at the University of Montreal have discovered that humans have a small part of the X chromosome that was once carried by Neanderthals. Their findings are published in the journal Molecular Biology and Evo
lution. Leading scientist, Damian Labuda, says that interbreeding between Neanderthals and modern humans occurred between 30,000 – 50,000 years ago. Labuda found evidence of this idea about ten years ago, but wasn’t completely sure until the Neanderthal genome was released in 2010. When comparing the modern human X chromosome to the Neanderthal X chromosome Labuda found that they shared DNA in all populations except sub-Saharan African. The related gene between modern humans and Neanderthals only codes for a protein, but this could be the first step in finding more similar DNA. The most important idea to come from this research is that this is proof that not only did Homo sapiens interact with Neanderthals, but they most certainly interbred.
An article in the New York Times tells the story of a pinky finger found in a Siberian Cave. According to the article the tip of the finger found is about 40,000 years old and gives insight to a new origin of humans. The bone of the girl’s pinky was genetically sequenced, from which scientists concluded that the finger belonged to a group known as Denisovans, who lived in Asia and vanished about 30,000 years ago. According to a paper published in the science journal Nature, after sequencing of the genome it has been noted that this group does share a common origin with Neanderthals, however, they were not involved in the gene flow from Neanderthals into Eurasians. Based on the two articles and the evidence presented I do not believe there is enough evidence to gather any concrete conclusion or suggest that the Denisovans are part of the human origin.
November 29th, 2011
kunal
It was recently discovered that many people living today have some type of neanderthal ancestor. It was previously thought that Neanderthals contributed little or none to our inheritance. This discovery comes from the sequencing of the genome of a neanderthal by the Max Planck Institute in Leipzig, Germany. Researchers are able to look at this genetic blueprint and understand and learn as much from it as our own sequenced genome. There are, however, many tasks that one must accomplish to get good, accurate data. For example, only a small amount of Neanderthal DNA was found in the bones among great amounts of bacteria and fungi. These types of hurdles needed to be carefully avoided. Once the genome is sequenced it can be compared to modern genomes to see where they differ. It was found that between 1% and 4% of the Eurasian genome comes from Neanderthals. This number is higher than anticipated. The study also confirmed that human ancestry can be traced back to Africa, a theory that is widely accepted. This theory says that the ancestors of humans were Homo sapiens, and they originated from Africa about 200,000 years ago and then spread across the world. When comparing the genomes, the genome of Non africans (from China,Europe, New Guinea) are closer to Neanderthals then African genomes. This is explained by limited gene flow or limited mating between Neanderthals and eurasians. The genes of Neanderthals (some of them) therefore, still live on in us. 
