Danish scientists from the University of Copenhagen have found a link between the domestication of the first animals by humans and the beginning of mass infections caused by deadly diseases such as plague and typhoid. The study was published in the scientific journal magazine Biorxiv.
Archaeological evidence has suggested that the risk of pathogen transmission from animals to humans increased when nomadic hunter-gatherers in Eurasia began establishing large rural communities about 12,000 years ago.
Recent discoveries in DNA analysis have finally allowed experts to test this hypothesis. A team of researchers, examining more than 405 billion DNA sequences collected from 1,313 ancient ruins on the Eurasian continent, managed to identify the genes of microbes.
According to preliminary information, a significant portion of the pathogens to which primitive herders were exposed came from animals and other external sources.
The bacterium, which specifically causes plague and lice-related relapsing fever, is first detected in human remains about 6,000 years ago, coinciding with the transition from hunter-gatherer societies to agriculture.
From this point on, DNA from zoonotic microbes (spreading from animals to humans) was consistently found in the remains examined.
The first societies in the Eurasian steppes to be exposed to zoonotic pathogens earlier than others may have had a great advantage. These pastoral communities not only had access to stable sources of meat and dairy products, but their bodies also had time to adapt to new animal pathogens.
“Our results provide the first direct evidence of the epidemiological transition of increasing zoonotic infectious disease burden following the emergence of agriculture in historical times,” said study author geogeneticist Martin Sikora.
Earlier archaeologists provenCrows were frequent guests of places where ancient people lived during the Paleolithic period.