Both the Neanderthals – who emerged around 400,000 years ago and lived in Europe and western Asia until 35,000 years ago – and the enigmatic Denisovans contributed DNA to present-day people.

The Denisovans are known only from DNA extracted from the finger bone of a girl unearthed at a cave in central Siberia. This 40,000-50,000-year-old bone fragment, as well as a rather large tooth from another individual, are all that is known of this species.

The tiny “pinky” bone yielded an entire genome sequence, allowing scientists to compare it to the DNA of modern people in order to better understand the legacy of ancient interbreeding.

Now, researchers have linked an unusual variant of the EPAS1 gene, which is involved in regulating the body’s production of haemoglobin – the molecule that carries oxygen in the blood – to the Denisovans.

When the body is exposed to the low oxygen levels encountered at high elevations, EPAS1 tells other genes in the body to become active, stimulating a response that includes the production of extra red blood cells.

“After the Denisovan DNA came into modern humans, it lingered in different Asian populations at low frequencies for a long time”, Prof Nielsen said.

“Then, when the ancestors of Tibetans moved to high altitudes, it favoured this genetic variant which then spread to the point where most Tibetans carry it today”.

The full family tree is even more complicated, as Denisovans interbred with Neanderthals directly, as well as a yet-unknown and very ancient hominid.

Very cool stuff. I keep hoping 23andme adds a Denisovan DNA analysis to accompany the Neanderthal analysis it already provides.

Via BBC News.

The new species, Deuteragenia ossarium, is named after graveyard ossuaries where thousands of bones are collected.

Female wasps pounce on spider prey and sting; her venom attacks the nervous system of the spider and paralyzes it. Then she drags the body of her immobilized victim back to her nest, a tunnel in the ground or a tubular hole in wood.

A single egg is laid on the spider, and the wasp walls it up alive in a tomb of spit and soil. When the egg hatches, the wasp larva eats the (still living) spider.

They sting like crazy as well; one sting and the person drops everything and screams. And keeps screaming. The recommended advice is to “lay down and scream” so as to avoid further injury by stumbling or tripping.

This particular species has an even more creative reproductive strategy (you knew it wasn’t going to end with just that, didn’t you?):

When the experimenters reared out the larval wasps from these nests, they were a species that had never been described before. The barricade of dead ant bodies radically reduced the rate of parasitism.

Why entomb bodies of ants? “Anting” is a well known behavior for several animals, including many bird species.

It’s thought the defensive chemicals of ants act as a repellant to parasites and predators. You aren’t wearing the skin of your enemy, you’re wearing the smell of your enemy.

Top image of the related “tarantula hawk” of Ecuador via Wikimedia Commons.

Via Wired. Also, if you are interested in the obscure reference in the title of this article, check it out over there on Wikipedia.

Killer whales may not be just one species but rather four or more, with each hunting different prey, living in their own kinds of groups, prowling their own unique ranges and speaking in distinct ways, according to new genetic research.

Until now, however, scientists had not proved different species of killer whales existed. Genetic analyses had been inconclusive because scientists hadn’t mapped the entire genome of the whales’ mitochondria.

[B]y using a relatively new method called highly parallel sequencing to decipher the entire genome of mitochondria from a worldwide sample of 139 killer whales from the North Pacific, the North Atlantic and the oceans surrounding Antarctica, “we were able to see clear differences among the species,” explained researcher Phillip Morin.

The results?

In Antarctica, there are actually two different species that are distinct enough from orca in other parts of the world that they probably diverged genetically about 150,000 years ago. One specializes in knocking seals off of ice; the other, the “Ross Sea killer whale” specialized on fish beneath the ice.

The transients of the North Pacific, marked by sparser vocalizations, less tightly-knit pods, and a preference for marine mammals for their prey, are even farther remote in kinship, having split off around 700,000 years ago.

Results for the residents of the Pacific, Antarctica, and the North Atlantic are murkier; these may be the same species, sub-species, or different species, but until more samples are acquired researchers aren’t sure.

And, well, do you want to be the one to ask a killer whale in the wild for a saliva sample?

Photo of a pair of transients via Wikimedia Commons.
Via NBC News.