By now, the story has rather disappeared. For whatever reason, the best-preserved material came from female remains, leaving an entire male genetic history in the dark.
In the end, however, Neanderthal (aka Neandertel) men now get to state their side, for a newly operational sequencing of their Y chromosome.
Researchers around the world collaborated to successfully identify male-specific DNA sequences from the remains of three Neanderthals recovered from sites in modern-day Russia, Spain, and Belgium.
All lived roughly from 38,000 to 53,000 years ago, essentially the hazy years of now extinct humans.
They were also compared with similar genes in their more eastern cousins, Denisovan, representing two sets of Siberian relics that lived around 70,000 and 120,000 years ago.
If we do not know any better, we can infer that these Neanderthal and Denisovan men would have similar chromosomes. Eventually, they were separated from the same stock, which divorced modern humans about 800,000 years ago, only their own separation was recent – about 400,000 years ago.
This was not what the researchers found. Rather the Y chromosome in Neanderthal was a closer match for us than Denisovans. ‘
“It was quite surprising for us,” says evolutionary geneticist Martin Petr, lead author of the study of the Max Planck Institute for Evolutionary Anthropology.
“We know from studying their autosomal DNA that Neandertals and Denisovans were closely related and humans living today are their more distant evolutionary cousins. Before we first looked at the data, we expected their Y. Chromosomes will show a similar picture. ”
This discrepancy means a swag occurred shortly after their separation, in which Neanderthal’s original Y chromosome was exchanged for another person like us.
Exactly why such an exchange took place is not clear.
We know that our ancestors today cannot keep their hands off each other (or pretty much any other human population) with frequent genetic mixing events, leaving a legacy of DNA in their own genome.
But it is not like leaving behind a small genetic recipe to combat a disease or malnutrition. This is a complete recipe book that potentially affects a wide range of male sexual and non-sexual characteristics.
One possibility is that this version of the Y chromosome was simply doing a better job.
“We speculate that given the important role of the Y chromosome in reproduction and fertility, the reduced evolutionary fitness of the Neandertal Y chromosome may have led to natural selection to favor the Y chromosome from early modern humans, ultimately petr. Have to say “.
Computer simulations showed that relatively small Neanderthal communities scattered across the continent could easily collect a bunch of problematic mutations through inbreeding.
A more robust version of a Y chromosome raised from humans could increase fertility, quickly gaining ground as it moved down the family line from father to sons.
Whoever those chromosome donors were, they eventually cast themselves out. Although more closely related to our modern global community, their bloodshed was also a dead end.
Achieving this level of detail from ancient male bones was a task in itself. Jokes about delicate masculinity, the Y chromosome is not exactly a solid piece of work.
In the study, researchers put together early human Y chromosomes using modern Y sequences as a template for a particular set. Sticking to as much shared DNA as possible, Probe also produced enough unique sequences to create the complete picture.
This is a technique we can use to fill even more of the missing chapters of Neanderthal’s past.
“If we can retrieve Y chromosome sequences from Neandertals that lived before this supposedly early introverted event, such as the 430,000-year-old Neandertals from Sima de los Huesos in Spain, we speculate that they still have the original Neandertal Y. Chromosomes. So Janet Kello, senior author at the Mexican Planck Institute for Evolutionary Anthropology, says it would be more similar to Denisovans than modern humans.
This is certainly possible, but given that this kind of reading is meant to give more twists than any modern reality show, we are sure to wonder about any set of male Neanderthal genes awaiting us or two. Have to do.
This research was published in Science.