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trend. “Neanderthals and Homo sapiens both
have small teeth, so I would suggest that their
shared ancestor also had small teeth, which
would suggest the big teeth in Denisovans
is something they evolved later,” she says.
A likely explanation is that they had to chew
tough or hard foods. Unfortunately, attempts
to recover traces of food from the teeth have
so far failed. However, if DNA in sediments
at Denisova cave is anything to go by,
Denisovans who lived there ate a range of
large animals, such as deer and horses. They
even seem to have tackled big carnivores
including snow leopards, bears and hyenas,
according to William Rendu at the National
Centre for Scientific Research in Bordeaux,
France, who led the analysis. Supporting
this, stone tools from the cave have traces
of animal fat on them. Rendu believes that
the Denisovans probably hunted with spears,
even though the wooden shafts haven’t
been preserved in Denisova cave. Hominins
appear to have been using spears for at least
300,000 years, so it wouldn’t be surprising
that the Denisovans could make them.Tech savvy
Meat can certainly be tough to chew, unless
you cook it. “There is some evidence of
fire in Denisova cave,” says Rendu. Indeed,
controlled fire use became common
in Eurasia after 400,000 years ago and
Neanderthals probably used several cooking
techniques. But the use of fire in Denisova
cave looks intermittent, so it isn’t clear if
Denisovans cooked too. If not, that might
explain their unusually large teeth.
However, Rendu notes that there is almost
no difference between what the Denisovans
and Neanderthals living in Denisova cave ate.
This suggests they had similar capabilities.
“Clearly, we should expect the same levels
of technology, same levels of thinking,” he
says. Artefacts unearthed by Shunkov and
his colleagues at the cave seem to back this
up. Almost 80,000 objects, laid down over
150,000 years, reveal a steady progression
from flat stone flakes to narrow blades and
chisels. This is exactly the technologicalWere Denisovans
a distinct species?
Studies of the Denisovans carefully
avoid calling them a species.
Whereas Neanderthals have
the species name Homo
neanderthalensis, Denisovans
are referred to as a “population”.
This partly reflects the fact that
we know so much less about
them, but there are other reasons.
Jean-Jacques Hublin at the Max
Planck Institute for Evolutionary
Anthropology in Leipzig, Germany,
points out that species names are
convenient labels we use to make
sense of the world, and there is no
hard dividing line between us and
Denisovans. “We are connected by
a chain of inter-fecundity that goes
back 65 million years to a small
sort of squirrel-like primate that
lived in a tree,” he says. Moreover,
Homo sapiens, Denisovans and
Neanderthals could all interbreed,
which by some definitions means
none is a separate species.
A further complication is that there
seem to have been two distinct
groups of Denisovans: those whose
genes are found in mainland Asia,
and those whose genes are found in
Melanesia. Lumping them together
may be an oversimplification.progression that Neanderthals and H. sapiens
were making at that time. Yet the researchers
argue that Denisovans made all these tools.
Such claims are hard to prove and some
people dispute this assertion. “You need to
have the stone tools in the cold, dead hand
of the hominin,” says Sheela Athreya at
Texas A&M University. And provenance is
especially difficult to establish at Denisova
because habitation by Denisovans and
Neanderthals overlapped. In 2018, geneticists
reported discovering that a 90,000-year-old
bone fragment belonged to a young girl
they nicknamed “Denny”, who had a
Neanderthal mother and Denisovan father.
Finding such a child of the two types of early
human would be astonishingly unlikely
unless interbreeding, and thus population
overlaps, were common.
Intriguingly, stone tools have also been
found in Baishiya Karst cave. “They date
back possibly around 190,000 years,” says
Fu, suggesting that Denisovans made
them. No details have been published, but
according to Hublin, “it’s quite different
from what they have in Denisova”.
Meanwhile, Shunkov has an even bigger
claim: by around 60,000 years ago, the
Denisovans were making jewellery. Artefacts
his team has found in Denisova cave include
bone beads, a marble ring, a button made
of mammoth ivory and a polished bracelet
of dark green rock. This claim is so hotly
disputed that many researchers are
unwilling to discuss it. But Viola notes
that Neanderthals made jewellery out of
feathers and eagle claws. He is comfortable
with the idea that Denisovans made similar
objects, but says that some of the finds look
too advanced. “That polished stone bracelet,
that’s a level of technology that we don’t
even see modern humans doing till less than
10,000 years ago. I don’t think Denisovans
could have done that.”
The other issue is the age. A 2019 analysis
led by Katerina Douka at the Max Planck
Institute for the Science of Human History
in Jena, Germany, concluded that the most
recent clear evidence of Denisovans in the
cave is no younger than 52,000 years old,Tools found in
Denisova cave
show steady
technological
progressSHUNKOV^ ET^ AL.^202
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