In March 2010, the world of paleoanthropology was shaken by the discovery of a new human species. Found in the Denisova Cave in Siberia, it was identified through an analysis of its mitochondrial DNA, followed by nuclear DNA in December. A video interview with anthropologist Silvana Condemi, who retraced the incredible story of this discovery in the book she co-authored, The Denisova Enigma.
In 2008, in the Denisova Cave, deep in the Altai Mountains of Siberia, paleoanthropologists unearthed a tiny piece of a phalanx. At first glance, this small bone fragment was too small to identify a species based on anatomical features.
Adding to the mystery was the presence of Neanderthal bones and teeth in nearby sites, so scientists were not surprised by this new find. However, this tiny bone fragment held a great enigma that would revolutionize the world of paleoanthropology and the history of human settlement on our planet. A look back at an extraordinary scientific investigation with anthropologist Silvana Condemi, co-author of The Denisova Enigma (Albin Michel) with journalist François Savatier, who answered questions from Sciences et Avenir in a video.
But Who Is Denisova?
In 2008, geneticist Svante Pääbo decided to examine this small bone, a tiny piece of a fifth finger phalanx that would turn out to belong to a teenage girl around fifteen years old. This scientist conducted a groundbreaking study in the world of paleoanthropology: an analysis of the mitochondrial DNA and nuclear DNA of the fragment.
In March 2010, Svante Pääbo published the results of the mitochondrial DNA analysis, a first shock for paleoanthropologists. A few months later, in December 2010, the scientist continued to reveal the genetic results obtained, this time with nuclear DNA, causing a second upheaval in the world of paleoanthropology. This year would be forever remembered.
This unprecedented approach confirmed that they were dealing with a new species of the genus Homo, the Denisovan species.
A Veil of Skepticism
While this research pointed to the discovery of Denisova, paleoanthropologists remained skeptical. Indeed, it was the first time that a species had been defined by genetics rather than by anatomical characteristics, as is usually the case in paleoanthropology. Calling it a new species seemed premature to them, and the bone fragment remained an enigma.
However, a second study was conducted, this time on the nuclear DNA. Once again, genetics confirmed the existence of Denisova as a new species. Nevertheless, further studies on the cave’s sediments and the identification of other bone fragments in Denisova, followed by the discovery of a second Denisovan, identified in Tibet in the Baishiya Cave, were needed to lift the veil of skepticism among paleoanthropologists.
Do We Have Denisovan Genes?
Our genes tell the story of our species, allowing us to trace our entire evolution and adaptations over time. Denisova is part of our family tree, but it remained to be seen if we still carry its genes.
Our evolution is linked to the interbreeding between different Homo species. Silvana Condemi, paleoanthropologist and co-author of The Denisova Enigma, explains that interbreeding allowed Sapiens to evolve and adapt to their environment: “The Denisovan heritage helped Homo sapiens survive.”
Genetics has also provided a chronological framework for the evolution of different Homo species. A strong connection between Neanderthals and Denisovans has been observed. Indeed, these two species lived during the same eras but in different geographical regions: Denisova is the contact zone between these two fossil populations.
Furthermore, genetics has discovered a first-generation hybrid, with a Neanderthal mother and a Denisovan father. However, while Neanderthal genes are spread across Europe and Asia, Denisovan genes are found only in Asian populations.
