Neanderthals and Denisovites – two relatives of modern humans – were roommates, literally, thousands of years in a remote Siberian cave, two new studies were discovered.
In ancient times, this cave would be a paradise for a real estate agent; it is the only place in the world that the Neanderthals, the Denizens, and perhaps even modern humans, lived together throughout history, researchers found.
The cave was so popular that the hominins (a group that includes people, our ancestors and our close relatives like chimps) lived there almost continuously and in hot and cold periods for the past 300,000 years, researchers say. [In Photos: Bones from a Denisovan-Neanderthal Hybrid]
By analyzing fossils and DNA, the researchers learned that the mysterious Denisovci lived in the cave for at least 200,000 to 50,000 years, and the Neanderthals lived there between 190,000 and 100,000 years.
It's not entirely out of the blue that the Neanderthals and the Denizens interfered. In 2018, researchers published a study in the Nature magazine about the bone fragment of a teenage girl who has a mother of Neanderthal and Father Denisovan, the first direct evidence that the two hominine groups intertwine.
The new research shows that this girl, whose remains were found in the Denisova cave, lived about 100,000 years ago, scientists say.
Getting a bonus
The researchers excavated the Denisova cave, located at the foot of the Altai Mountains in Siberia, for the past 40 years.
In 2010, the cave gained worldwide recognition when scientists announced that they had found the bone on a finger of a previously unknown hominine and published their genome. They named the Denisovani (de-NES-so-vans) hominid named after the cave.
However, until now, the researchers had several artifacts to date, so they were not sure exactly when the inhabitants of the cave lived there. Now, two new studies reveal a chronology for the inhabitants of the cave.
In a study, researchers in Australia and Russia used optical dating to determine the age of caves sediments. They could not use a radioactive node because it could certainly give away organic items just 50,000 years ago. By contrast, optic giving allows scientists to find out when grainy quarks and feldspars in the soil were last exposed to sunlight.
In another study, the researchers in Germany, the United Kingdom, Australia, Russia, and Canada reviewed the predictable decomposition of radioactive carbon (a radioactive carbon) isotope to find out the age of fragments of bones, teeth and coal found in the upper layers of the page; and then created a statistical model that integrates all newly discovered dates of the cave.
"We had to invent some new methods to find the deepest and oldest sites and to create a robust chronology of the sediments in the Denisova cave," says co-researcher Bo Lee, associate professor at the Earth, Atmospheric and Life Sciences University of Wollongong in Australia, the statement said.
In addition, the new statistical model has helped "to include all the evidence of dating available for these small and isolated fossils, which could easily be displaced after sedimentation," says research researcher Katerina Duka, an archeological scientist from the Max Planck Human Institute history in Germany, the statement said. [Denisovan Gallery: Tracing the Genetics of Human Ancestors]
However, questions about dated material remain in the cave. For example, "do human fossils come from human occupations or, as they say, carnivorous activity, and have they been transported away from their original disposal site?" research researcher Chris Stringer, a research leader of human origin at the London Natural History Museum, asked.
A puzzle for the cave continues: Did modern people live there? Our species (Homo sapiens) was present in other parts of Asia, 50,000 years ago, but it is unclear whether there is one H. sapiens interaction with the Denisovites in the cave. This is because scientists have yet to find any fossil or genetic traces of modern humans in the cave, although researchers have found a hominine bone dating from 50,000 to 46,000 years ago. The team could not get the DNA from it, so it's not clear which species belonged to the bones.
In addition, it is possible for modern people to make some of the artifacts in the cave.
"Another open question is whether the Denisovites or modern people have made the oldest bones and personal ornaments [tooth pendants] discovered in the cave, "says Tom Hajdam, a professor of archeology at the University of Oxford, who worked on a study on radioactive gas." With direct dates of 43,000 to 49,000 years ago, they are the earliest such artifacts known from northern Eurasia. "
But Stringer said he would put his money on early modern humans.
"Early modern people can be mapped elsewhere on this date, for example in Ust & # 39; Ishim in Siberia," Streetinger told Live Science in an e-mail. "But the authors of [radiocarbon dating] paper, and surprisingly argue that it is most reasonable to assume that the Denizens are responsible, although no Denisov is still known as late in that order.
"Only more discoveries and more research can solve this issue satisfactorily," Stringer added.
Both studies were published yesterday (30 January) in the journal Nature.
Originally published on Science Live.