Scientists studying the origins of humans have made tremendous advances in recent advances in ancient DNA analysis techniques. New research is based on human tooth fossil analysis, an alternative way to go back in time.
This study, published in Science Advances, Previous date The age of the last common ancestor of the present scientific consensussapient (Our species) and NeandertalWhich 800,000 years Not 400,000 to 600,000 years.
However, this study, led by Aida Gomez-Robles of University College London, was discussed by anthropologists, some of which question the accuracy of the methodology used by researchers.
The study starts at about 30 years old. Molar and molar It is found in the cave of Saina de los Huesos in Spain, where the first men and women of the Neanderthals were among them. She also analyzed. fossil From seven other ancient mankind
The teeth of Sima de los Huesos are 430,000 years in 2014 with reliable technology. This dating already has its own "car"Between Safian and Neanderthals happened 400,000 years ago." But when?
To calculate this time Common ancestor, The researcher has a human tooth shape A certain rhythm. The goal is to go back in time at the same time and discover the ancestors who were able to lead to Sima de los Huesos human teeth and modern human teeth.
According to this calculation, Aida Gomez-Robles came to the conclusion that our ancestors and Neanderthals were "split" 800,000 years ago.
The immediate consequence of this work is that as a common ancestor many people seek, they will remove Homel heidelbergensis.
Although this study alone does not solve the controversy over the origin of mankind,It gives us a more accurate picture."It is especially difficult to extract DNA from very old fossils because it is very difficult and impossible.
The fact that DNA and teeth record different dates supports the notion that species do not separate immediately, on A very long periodIn the meantime, individuals begin to differentiate, but continue to mix and reproduce.
"Disagreements between neanderthals and modern man, or between some species, do not happen at any particular point in time."The study authors said.
"Today we hybrid Between Neandertals and modern people."
Mirjana Roksandic, an anthropologist at the University of Winnipeg, recently published a paper describing H. heidelbergensis as a non-Neanderthal. She respects what her sister did.
"I found the moment when Neandertal started drawing the chart in her own way, which is a very important result," she says.
"The teeth are fossilized and contain a lot of information.. "
Others are more moderate. Anthropologist Bridget Alex, at Harvard, called the new methodology "Helpful"He emphasized that genetic changes and physical and physiological changes in evolution can occur at different rates.
Susan Cachel, a professor of human evolution at Rutgers University, criticizes this work. "If anatomically modern humans and the ancestors of Neanderthals are not derived from Homo heidelbergensis, where did they come from? Unknown and mysterious ancestor?".
"Living humans have a special tooth variation."The current Indians have a rare form of premolars," she said, adding that she would undermine one of the homes of the Iida Gomez-Robles model.It may have appeared in the last 15,000 or 20,000 years."
"Therefore, I argue that the rhythm of tooth evolution does not change."