Revealing our shared past through archaeological findings

In 2010, scientists discovered a finger bone in a cave in Siberia. Genetic analysis revealed that it belonged to a newly discovered human species, which was named ‘Denisovan’, after the cave.

‘When I visited the site a few years later, I saw that the vast majority of material coming out of the ground was in tiny fragments’, recalls Katerina Douka, who is based at the Max Planck Institute for the Science of Human History in Jena, Germany. ‘It was then that I had a eureka moment – what if we used new molecular methods to screen and pick out human bones?’

Douka realised that well-preserved bone fragments from the frigid Siberian cave would still contain traces of proteins, especially collagen. Researchers from the University of York in the UK had previously developed a molecular technique to screen for protein-containing material such as animal bones, parchment or leather. Douka thought to apply this technique to fragments of human bone which otherwise could not be identified because they were so small.

Identifying our mixed heritage

In the pilot study with material from Denisovan cave, Douka and her colleagues made an incredible discovery – the fragment of a bone that belonged to a girl, perhaps 13 years old, whose mother was a Neanderthal and father was a Denisovan. This proved conclusively that these two human species interbred. The discovery enabled Douka to secure ERC funding and continue her ground-breaking work.

Douka aims to build on this remarkable discovery, and to identify more human fossils using this collagen fingerprinting method. ‘The screening tool is fast – we can go through about 1,000 bones a week – and it is relatively cheap’, explains Douka. Once a human bone is identified, DNA methodologies are applied to learn more about the fragment – which human species it belonged to, and using methods such as radiocarbon dating, how old it is, for example.

‘This work is so fascinating, and also so relevant today’, says Douka. ‘These bone fragments belonged to people who died thousands of years ago, but who are now helping to shine a light on modern humanity.’

Modern humans have inherited a lot of genetic material from human species that no longer exist. Research into the SARS-CoV-2 virus, for example, has shown that genes inherited from Neanderthals can influence an individual’s response to infection. ‘This shows how this period of interbreeding continues to shape us’, says Douka.

Archaeology with global impact

The project promises to reveal more. The modern techniques being applied require just fragments of bone that contain enough genetic material to work with. Furthermore, this new era of scientific archaeology is reaching every corner of the world, thanks in part to Douka’s research. An impressive global network of researchers and facilities is being built.

‘Our project is setting up what we call ZooMS (Zooarchaeology by Mass Spectrometry) labs in parts of the world where such facilities did not previously exist’, says Douka. ‘We have already helped build a new lab in Novosibirsk, Russia and one in China. We are also committed to sharing data and knowledge. This means that local scientists can work on sites without having to send samples to Europe, or wait for western scientists to arrive.’

The project team has also collaborated with an NGO to identify ivory artefacts bought on the European black market, and with museums to carry out the non-destructive sampling of artefacts. A benefit of collagen fingerprinting is that it requires just a tiny sample.

Finally, Douka hopes that the project’s discoveries will help people to realise that human history expands well beyond the relatively recent formation of countries and nationalities, to a time when we were all truly citizens of the world.

‘I think that understanding our human evolution can help to break down ideologies that rely on racial superiority’, she says. ‘Issues like skin colour are so ephemeral – 7,000 years ago, humans arriving in England may have looked similar to sub-Saharan Africans. This project is about recognising our shared humanity.’

How the ERC transformed science - interview with Katerina Douka

About the researcher

Katerina Douka is an archaeological scientist and Group Leader of the Department of Archaeology at the Max Planck Institute for the Science of Human History in Jena, Germany. She specialises in radiocarbon dating and the application of chronometric and biomolecular methodologies. She won an ERC Starting Grant in 2016.