Radiocarbon dating hominids
An initial morphological characterization of the toe bone led to the suggestion that it may have belonged to a Neanderthal-Denisovan hybrid individual, although a critic suggested that the morphology was inconclusive. Some older findings may or may not belong to the Denisovan line.
These include the skulls from Dali and Maba, and a number of more fragmentary remains from Asia.
The mt DNA analysis further suggested that this new hominin species was the result of an earlier migration out of Africa, distinct from the later out-of-Africa migrations associated with modern humans, but also distinct from the even earlier African exodus of Homo erectus.
Later in 2010, a second paper from the Svante Pääbo group reported the prior discovery, in 2000, of a third upper molar from a young adult, dating from about the same time (the finger was from level 11 in the cave sequence, the tooth from level 11.1).
In April 2014, a first glimpse into the epigenetics of the Denisovan was gained with the publication of the full DNA methylation of the Denisovan and the Neanderthal.
The reconstructed DNA methylation map allowed researchers to assess gene activity levels throughout the Denisovan genome and compare them to modern humans and to the Neanderthal.
Surprisingly, it belonged to a female individual, indicating that the Denisovans were extremely robust, perhaps similar in build to the Neanderthals.
The tooth that has been characterized shares no derived morphological features with Neanderthal or modern humans.
The cool climate of the Denisova Cave preserved the DNA.
The Denisova Cave is located in south-western Siberia, in the Altai Mountains near the border with China and Mongolia.
It is named after Denis, a Russian hermit who lived there in the 18th century.
So far, the fossils of four distinct Denisovans from Denisova Cave have been identified through their DNA: Denisova 2, Denisova 3, Denisova 4, and Denisova 8.
Denisova 2 and Denisova 3 are prepubescent or adolescent females, while Denisova 4 and Denisova 8 are adult males.
From this analysis, they concluded, in spite of the apparent divergence of their mitochondrial sequence, that the Denisova population shared a common branch with Neanderthals from the lineage leading to modern African humans.