Our genomes are riddled with the detritus of ancient viruses. They infected our hominid ancestors tens of millions of years ago, inserting their genes into the DNA of their hosts.

Today, we carry about 100,000 genetic remnants of this invasion. So-called endogenous retroviruses make up 8 percent of the human genome.

Mostly, these genetic fragments are generally nothing more than molecular fossils. Over thousands of generations, they have mutated so much that they cannot replicate in our cells. And our cells keep the viral DNA muzzled to minimize the harm it might cause.

Continue reading “Ancient Viruses, Once Foes, May Now Serve as Friends” →

In 1998, Dr. Philip A. Starr started putting electrodes in people’s brains.

A neurosurgeon at the University of California, San Francisco, Dr. Starr was treating people with Parkinson’s disease, which slowly destroys essential bits of brain tissue, robbing people of control of their bodies. At first, drugs had given his patients some relief, but now they needed more help.

After the surgery, Dr. Starr closed up his patients’ skulls and switched on the electrodes, releasing a steady buzz of electric pulses in their brains. For many patients, the effect was immediate.

Continue reading “Clues to How an Electric Treatment for Parkinson’s Works” →

Gert Stulp stands 6 feet, 7 inches tall. His height makes him especially self-conscious at scientific conferences when he rises to describe his research as a demographer at the London School of Tropical Medicine. “It’s always quite embarrassing,” he said.

Dr. Stulp, who is Dutch, studies why his fellow citizens are so tall.

Today, the Dutch are on average the tallest people on the planet. Just 150 years ago, they were relatively short. In 1860, the average Dutch soldier in the Netherlands was just 5 feet 5 inches. American men were 2.7 inches taller.

Continue reading “Natural Selection May Help Account for Dutch Height Advantage” →