Aside from being able to call Ice Age Europe their home, Neanderthals and woolly mammoths might not appear to have all that much in common. But a study recently published in the journal Human Biology suggests otherwise.
Researchers from Tel Aviv University (TAU) in Israel have studied genetic adaptions in the two now-extinct species, finding they both shared molecular characteristics of adaption to cold surroundings.
"They say you are what you eat," Ran Barkai from TAU's Department of Archaeology and Ancient Near Eastern Cultures said in a statement.
"This was especially true of Neanderthals; they ate mammoths but were apparently also genetically similar to mammoths."
Like Neanderthals, Eurasian woolly mammoths (Mammuthus primigenius) were direct descendants of an Africa-dwelling ancestor – in their case, the Mammuthus rumanus. Paleontologists believe these older mammoths spread into East Eurasia some 3.5 million years ago, where they evolved and adapted to the cooler climes.
M. primigenius evolved around 600,000 years ago around Eurasia's Arctic peninsula and displays different physiology to its ancestors. Specifically, one that involves gene-based adaption to the frigid weather.
Neanderthals (Homo neanderthalensis) evolved a little later, around 400,000 years ago, in Europe before spreading into Asia and the Levant. Their closest ancestor is believed to have settled in Eurasia having migrated from Africa around 1.2 million years ago.
"Neanderthals and mammoths lived together in Europe during the Ice Age," explained Barkai.
"The evidence suggests that Neanderthals hunted and ate mammoths for tens of thousands of years and were actually physically dependent on calories extracted from mammoths for their successful adaptation."
But it seems the pair had more than that in common. Barkai and his team tested the similarity of three genetic variants and alleles specific to cold weather in both woolly mammoths and Neanderthals. These can be described as alternative forms of a gene caused by a mutation found in the same place on a chromosome.
One, the LEPR gene, is linked to thermogenesis (the production of heat) as well as the regulation of fat storage and adipose tissue. Another had to do with keratin protein activity and the third involved skin and hair pigmentation variants in the MC1R and SLC7A11 genes.
"Our observations present the likelihood of resemblance between numerous molecular variants that resulted in similar cold-adapted epigenetic traits of two species, both of which evolved in Eurasia from an African ancestor," co-author Meidad Kislev, also from TAU's Department of Archaeology and Ancient Near Eastern Cultures, said in a statement.
"These remarkable findings offer supporting evidence for the contention regarding the nature of convergent evolution through molecular resemblance, in which similarities in genetic variants between adapted species are present."
Interesting as it is, archaeologically and evolutionarily speaking, that the two (very different) species evolved similar traits at a molecular level co-currently, the team also hopes this discovery is a positive one for the two species' extant relatives.
"At a time when proboscideans are under threat of disappearance from the world due to the ugly human greed for ivory, highlighting our shared history and similarities with elephants and mammoths might be a point worth taking into consideration," Barkai added.