The introduction of a bacteria that causes plague, Yersinia pestis, in Siberia thousands of years ago might have dealt a blow to the population of the region back then, Science news reports, citing a new study published in Science Advances on 6 January.
The study, conducted by a team led by two evolutionary geneticists from Stockholm University, Gulşah Merve Kilinç and Anders Gotherstrom, involved the extraction of DNA from skeletal remains previously discovered in Eastern Siberia.
The subsequent analysis of these samples yielded the discovery of Yersinia pestis, in two ancient denizens of Siberia; one of the infectees lived approximately 4,400 years ago, while the other was dated back to about 3,800 years ago.
The researchers further established that genetic diversity in the samples they've studied witnessed a decline around from around 4,700 to 4,400 years ago, "possibly the result of population collapse", as the media outlet points out.
Gotherstrom, however, pointed out that it is still unclear how the bacteria that they've discovered made its way to Siberia, or whether it actually caused "widespread infections and death" there.
Hendrik Poinar, an evolutionary geneticist from McMaster University in Canada who did not participate in the study in question, also argued that the ancient Siberians might have been infected with a non-virulent type of Yersinia pestis which "wouldn’t have killed enough people to alter the genetic structure of Siberians".
He further noted that genetic data from only two individuals is simply insufficient to confirm whether they were carrying a virulent strain of the bacteria.