Around 11,000 years ago, humans first set foot in the driest place on Earth.

The Atacama Desert straddles the Andes Mountains, reaching into parts of Chile, Peru, Bolivia and Argentina. Little rain falls on the desert — some spots haven’t received a single drop in recorded history.

But the people who arrived at the Atacama managed to turn it into a home. Some Atacameños, as they are known today, fished the Pacific. Others hunted game and herded livestock in the highlands. They mummified their dead, decorating them with ceremonial wigs before leaving them in the mountains.

Continue reading “An Unlikely Driver of Evolution: Arsenic” →

Last month, a team of scientists announced what could prove to be an enormous step forward in the fight against H.I.V.

Scientists at Scripps Research Institute said they had developed an artificial antibody that, once in the blood, grabbed hold of the virus and inactivated it. The molecule can eliminate H.I.V. from infected monkeys and protect them from future infections.

But this treatment is not a vaccine, not in any ordinary sense. By delivering synthetic genes into the muscles of the monkeys, the scientists are essentially re-engineering the animals to resist disease. Researchers are testing this novel approach not just against H.I.V., but also Ebola, malaria, influenza and hepatitis.

Continue reading “Protection Without a Vaccine” →

T. Ryan Gregory’s lab at the University of Guelph in Ontario is a sort of genomic menagerie, stocked with creatures, living and dead, waiting to have their DNA laid bare. Scorpions lurk in their terrariums. Tarantulas doze under bowls. Flash-frozen spiders and crustaceans — collected by Gregory, an evolutionary biologist, and his students on expeditions to the Arctic — lie piled in beige metal tanks of liquid nitrogen. A bank of standing freezers holds samples of mollusks, moths and beetles. The cabinets are crammed with slides splashed with the fuchsia-stained genomes of fruit bats, Siamese fighting fish and ostriches.

Continue reading “Is Most of Our DNA Garbage?” →