Denisovans in India

We homo sapiens are the only surviving humans around. In fact, it has been that way for the last 10,000 years. We tend to forget that at some point, there were many types of humans (of genus Homo) on earth like the Homo neanderthalensis (Neanderthals), Homo soloensis,  Homo floresiensis, Homo erectus, and Homo denisova (Denisovans).  While the Neanderthals are the most famous among all of these, sapiens co-existed with the others and intermingled with them. We may even have caused their extinction

While all of us have some Neanderthal ancestry (1 – 4%), some of us (Australians, Indians) have more Denisovan ancestry (5%). This intermingling happened much after the Neanderthal mixture. This happened because all these three — sapiens, Neanderthals and Denisovans — were not different species, but of the same species. They produced offsprings together.
A new paper analyzed the amount of Denisovan ancestry and found that Indians have the largest admixture after the people in Australia. Among the Indians, the largest were among people in the Himalayan region and South and Central India. What is not known is this: Was there a single introgression of Denisovans into sapiens and it got diluted in various rates among the populations of the world or there were three different introgressions.
Looking at this paper, Sunil Deepak asks an interesting question.

The Battle over Neanderthals

A reconstruction of a Neanderthal male from the Neanderthal Museum.
A reconstruction of a Neanderthal male from the Neanderthal Museum (via Wikipedia)

A NOVA documentary presented the hypothesis that Neanderthals knew how to fashion a tool, manufacture glue from birch bark, had language skills, and on top of it had ritual, art and symbolism. It turns out that this issue is not settled and there  is debate about the skill set of Neanderthals.

Where Zilhão sees a clear pattern, sceptics see uncertainties. Harold Dibble, an anthropologist at the University of Pennsylvania in Philadelphia, is re-examining supposed Neanderthal burial sites. At one, the French cave of Roc de Marsal, he says that what seemed to be a deliberately excavated grave is actually a natural pit. At another, La Ferrassie, he sees evidence that sediments swept into the cave by water — not grieving kin — could have buried Neanderthal remains.
As for the ochre crayons, Dibble is dismissive. “You see some wear on a piece of ochre and soon you’ve got Neanderthal body painting,” he says. “What a lot of logical leaps.” He and others say that the pigment has many possible uses: as an insect repellent, a preservative for food or animal skins, an ingredient in adhesives. Even Wil Roebroeks of the University of Leiden in the Netherlands, who found evidence for ochre use as early as 250,000 years ago at a Dutch Neanderthal site7, says that Zilhão “jumps too fast from the presence of ochre to body decoration”.
Ask Dibble, Hublin and other sceptics what would persuade them that Neanderthals had minds like ours, and their answer is simple: a pattern of art or other sophisticated symbolic expression from a time when no modern humans could possibly have been around. “But I don’t think it exists,” says Hublin. [Neanderthal culture: Old masters]

Decoding Neanderthals (NOVA)

As humans left Africa and reached Europe, they found another hominid species which had left Africa much earlier — 800,000 years back — and had colonized specific parts of Europe. For about 10,000 years, humans and the Neanderthals co-existed; the magnificent Chauvet caves were built during this period. Then they just disappeared from the face of earth. Thus a species, which had survived for so long battling against an unforgiving nature, simply vanished and the reason behind that remains a mystery. Was it because they were now battling for the same resources as humans and could not win? Or was it because Neanderthals, who lacked art, language and technology, were wiped out by a superior species?
The new NOVA documentary, based on evidence from archaeology and genetic studies, does an image makeover of Neanderthals based on evidence from archaeology and genetics.

  1. It turns out that they had skills to use a set of carefully designed strikes to convert a flint stone into a flake with sharp edges. This flake could then be used to cut meat or as a weapon when attached to a pole.
  2. For attaching the flake to a pole, they brewed their own glue from birch bark using a dry distillation process which involved controlled heating.
  3. They had some language skills which was used to convey the above technologies to their peers.
  4. They also interbred with humans; everyone except Africans has a percentage of Neanderthal gene in them. Italians have the most.
  5. They had ritual, art and symbolism. They may have attempted body painting and also used grave goods as part of a burial ritual.

Since the program covered a lot of aspects of Neanderthal life, it fast-forwarded through one of the interesting questions about why they perished. One theory was offered: they were bred out by humans through interaction and absorption. Though it led to their extinction, this interbreeding might have helped us by providing with immunity to pathogens.
The entire program is available online

Watch Decoding Neanderthals on PBS. See more from NOVA.