I know news of this discovery has
been around for a while but I missed it until a report on the 88th Annual Meeting of the American
Association of Physical Anthropologists came to my attention.
Parietal fragments, discovered back in 2016 were, at last, confirmed by DNA analysis to be that of a Denisovan. These were the subject of a Podium presentation. Here's the abstract from the conference:
A parietal fragment
from Denisova cave (see here) Viola, B.T. et al. (2019)
The Denisovans are an Asian sister group of Neanderthals, originally
described based on ancient DNA from a phalanx fragment from Denisova Cave
(Altai Mountains, Russian Federation). Since then, three teeth found in the
cave have been identified from this group. Genetic data indicates that this
population contributed genes to modern humans across large parts of Asia and in
Melanesia, but currently, no fossils from outside Denisova Cave have been
clearly attributed to Denisovans. One reason for this is that the extremely
limited morphological evidence hampers comparisons. A newly discovered parietal
fragment, Denisova 13, attributed to the
Denisovans based on its mtDNA, gives us a first glimpse at the Denisovan
cranial morphology.
Denisova 13 derives from the South Gallery of
Denisova cave, although due to a collapse of the section, its stratigraphic
position is not secure. Based on its preservation and the accompanying sediments
we tentatively attribute it to Layer 22.The specimen consists of two adjoining
fragments of the posterior half of the left parietal, extending about 78 mm
laterally of lambda, and about 51 mm anteriorly,
preserving portions of both the sagittal and lambdoid sutures.
We compare Denisova 13 to a large sample
of recent and fossil modern humans, Neanderthals and Middle Pleistocene Homo, using geometric morphometrics based on
three-dimensional landmarks and sliding semilandmarks collected on
computed-tomographic scans and surface scans.
We
will discuss the implications of these comparisons to our understanding of
Middle and Late Pleistocene hominins in Asia.
At a press conference Viola is quoted by the Science Alert (2019), as
saying: "It's very nice that we finally have fragments like
this," says Viola. "It's not a full skull, but it's a piece of a
skull. It gives us more. Compared to the finger and the teeth, it's nice to
have." But, he adds, it's hardly a full skeleton.
"We're always greedy,"
he laughs. "We want more."
A
report by Science News (2019) gave a little more detail: "Viola, of the
University of Toronto, and his colleagues compared a digital reconstruction of
the skull fragment with corresponding parts of 112 present-day human skulls and
30 Stone Age Homo skulls, including Homo sapiens and Neandertals. The Denisovan
find didn’t fit neatly into any previously known Homo species. Some features
linked the Denisovan fossil to Neandertals and to a 430,000-year old Spanish
Homo species that had Denisovan ancestry. The Denisovan skull fragment is
surprisingly thick, more like cranial bones of Stone Age Homo erectus, Viola
said."
Scientist at Denisova Cave. Second left Katherina Douka of the Max
Planck Institute, part of the team that successfully extracted DNA from the
parietal fragments. From NY Times (2019).
References:
Science News (2019).
"The first known fossil of a Denisovan skull has
been found in a Siberian cave" at https://www.sciencenews.org/article/first-fossil-denisovan-skull-cave-siberia accessed
09.04.19
Science Alert
(2019). "Scientists Just Confirmed The Discovery
of The First Ever Denisovan Skull Fragments" at: https://www.sciencealert.com/first-confirmed-denisovan-skull-piece-found accessed
09.04.19
New York Times
(2019). "High Ceilings and a Lovely View: Denisova Cave Was Home to a Lost
Branch of Humanity” at: https://www.nytimes.com/2019/01/30/science/neanderthals-denisovans-humans.html accessed
09.04.19
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