According to genome analysis of a bone discovered in a Siberian cave, a female who died around 90,000 years ago was half Neanderthal and half Denisovan. This is the first time scientists have identified an ancient person whose parents came from different human groups. Do you know the name of the only Hybrid hominin?
Denny is the only known person whose parents were of two different human species. She lived 90,000 years ago in Central Asia, where a fragment of her bone was discovered in 2012. Her father was a Denisovan, and her mother was a Neanderthal.
Denny, the Only Human Hybrid
The genome analysis was carried out on a single bone fragment recovered from Denisova Cave in Russia’s Altai Mountains by a team led by palaeogeneticists Viviane Slon and Svante Pääbo of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. This cave is named after the Denisovans, a group of extinct humans discovered in 2008 based on DNA sequences from the tip of a finger bone. Neanderthals lived in the Altai region, specifically in the cave. (Source: Nature)
Denny’s Ancestry
Denny’s remains were discovered several years ago by Pääbo’s team while searching through a collection of over 2,000 unidentified bone fragments for signs of human proteins. In a 2016 paper4, they used radiocarbon dating to determine that the bone belonged to a hominin who lived more than 50,000 years ago, the upper limit of the dating technique; Pääbo believes the specimen is around 90,000 years old.
They then sequenced the specimen’s mitochondrial DNA, which is the DNA found inside cells’ energy converters and compared it to other ancient human sequences. This analysis revealed that the mitochondrial DNA in the specimen came from a Neanderthal.
However, this was only half of the story. Mitochondrial DNA is inherited from the mother and represents only one line of inheritance, obscuring the father’s identity and the individual’s broader ancestry.
The team wanted to better understand the specimen’s ancestry by sequencing its genome and comparing the variation in its DNA to that of three other hominins, a Neanderthal and a Denisovan, both found in Denisova Cave, and a modern-day African human. Around 40% of the DNA fragments from the specimen matched Neanderthal DNA, while the remaining 40% matched Denisovan DNA. The researchers also determined that the fragment came from a female by sequencing the sex chromosomes, and the thickness of the bone suggested she was at least 13 years old. (Source: Nature)
Two Different Distinct Humans
The researchers examined sites in the genome where Neanderthal and Denisovan genetics differed from determining which of these options was more likely. They compared Denny’s DNA fragments to the genomes of the two ancient hominins at each of these locations.
More than 40% of the time, one of the DNA fragments matched the Neanderthal genome, while the other compared a Denisovan genome, implying that she got one set of chromosomes from a Neanderthal and the different from a Denisovan. Denny was the direct offspring of two distinct humans. (Source: Nature)
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