In the latest episode of Genetics Unzipped, presenter Dr Kat Arney chats to researchers who are delving back into the ancient past, winding the clock back thousands of years to discover the stories of Denisovans and direwolves that they are now able to read in the fragments of DNA left in bones or even dirt.
For a field focusing on things that died thousands of years ago, ancient DNA research is very much alive. New genetic tools and technologies are allowing scientists to delve back tens or even hundreds of thousands of years into the past in a way that was never possible before.
All of these advances are opening a new window into the past to understand the species that were around in different parts of the world, how they interacted together, and why – in the case of the ones that have gone extinct – they’re no longer with us.
Why did the direwolf go extinct?
One of the people who’s digging into the past through the use of ancient DNA to understand why a species might have vanished is Dr Kieren Mitchell from the University of Adelaide. And while his species of choice – the direwolf – has long since gone extinct, many people don’t know that they were real in the first place.
“A lot of people don’t actually realise that they were a real animal, as real as lions and tigers and other things that we see around us today. They’re not just mythical animals that you see on TV programmes like Game of Thrones or read about in fantasy novels,” he explains.
“They were probably a little bit bigger than living grey wolves, maybe ten percent, twenty percent bigger, but they were a bit stockier and heavier than a grey wolf would be. So you certainly wouldn’t be riding one into battle or anything like that, but they’d be a pretty formidable sight if you came across one or, more likely, if you came across a pack of them.”
Kieren and his colleagues have been analysing DNA from direwolf bones and discovered some unusual clues as to why these formidable animals died out. Curiously, it might have been because they were just too choosy about their meals and their mates.
Digging for DNA from ancient humans
Moving from direwolves to our own species, Kat also spoke with Dr Benjamin Vernot – a researcher at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. Rather than studying bones, he’s been digging for DNA in cave dirt in order to unearth the stories from our ancient human ancestors.
One of the things that surprised him most about analysing this ancient DNA is that he and his team didn’t uncover a complete mix of DNA, but instead could find traces of individual Neanderthals who were alive tens of thousands of years ago.
“My expectation going in was one hundred percent that it was just going to be a mess of DNA – you have groups of Neanderthals living in this cave, working in this cave, so you’re not going to expect to be able to identify individual people,” he says.
“Actually, several of the sediment samples really look like they only have one person in them. All male, all the same mitochondrial DNA. I think the simplest explanation is that it comes from one individual, but it could have come from two brothers or a mother and daughter or something like that.”
Listen to the Genetics Unzipped podcast
Listen to the whole episode and find show notes and a full transcript at GeneticsUnzipped.com.
Genetics Unzipped is the podcast from the UK Genetics Society, presented by award-winning science communicator Dr Kat Arney and produced by First Create the Media. Follow Genetics Unzipped on Twitter @geneticsunzip, and the Genetics Society at @GenSocUK