Inbreeding increased in Neanderthals and influenced their decline

An badysis of the fossil remains of the 13 Neanderthals found in the El Sidrón cave, all members of the same family, indicates that they were strongly inbreeded.

Researchers led by Antonio Rosas, of the Higher Council for Scientific Research (CSIC), have detected up to 17 conbad anomalies that can be observed throughout the skeleton of these paleolithic humans. These genetic singularities have been discovered in the nose, jaw, ribs, foot and wrist, among other parts of the body. The work is published in the latest issue of Scientific Reports.

"The extinction of Neanderthals was probably due to a combination of ecological and demographic factors, including interaction with modern humans, especially Neanderthals living in small groups and geographically separated from each other, so they were As a result, they began to cross between members of the same family and, over time, the group was further reduced and inbreeding increased.This endogamy, maintained over time, could result in a significant decrease in the biological variability of Neanderthal, "says Antonio Rosas.

The study of the family group of El Sidrón composed of 13 individuals revealed up to 17 conbad anomalies distributed throughout the skeleton. All shared by several members of the group. The group consisted of seven adults (four women and three men), three adolescents and three children.

"For example, at least four of the 13 Neanderthals in El Sidrón had an abnormality in the closure of the anterior or posterior arch of the cervical vertebra." Another striking case is the presence of conbad anomalies in the scaphoid (a wrist bone), "explains Luis Ríos, first signatory of the article, who works for the paleoanthropology group at the National Museum of Science. natural resources of the CSIC.

In some cases, the researchers recovered only small bone remains belonging to one of the 13 Neanderthals, making it impossible to study all the conbad anomalies that each of the Neanderthals of El Sidrón might have. For this reason, it is not excluded that these singularities and others could have been repeated in more individuals of the Asturias group.

"These osteological findings are the first to support the general picture of Neanderthal paleogenetics, and studies in several samples, including those from El Sidrón, indicate high levels of consanguinity, which have been maintained. in time and a possible increase of the last groups of Neanderthals who survived, "Ríos explains.

The information obtained from the Neanderthals of El Sidrón is in agreement with the genetic studies of the fossil remains of other European Neanderthals, such as those of the Croatian cave of Vindija and those of the Altai, in Siberia. . According to the results, there was also consanguinity in both cases. Moreover, in Altai, there was consanguinity, that is to say, a progeny between half-brothers.

The fossils of the El Sidrón cave in Piloña (Asturias) represent the most complete and abundant collection of Neanderthal remains from the Iberian Peninsula. During excavation work between 2000 and 2013, more than 2,500 bone remains were found in at least 13 Neanderthals that lived there about 49,000 years ago.

The badysis of the remains of Neanderthal skeleton from El Sidrón allowed to draw many conclusions about the life of these prehistoric human communities. It has been proven that they divided the work according to bad, that they knew the medicinal use of certain plants, that their diet included mushrooms, pine nuts and moss and that they practiced cannibalism .