When you drive toward an intersection, the sight of the light turning red will (or should) make you step on the brake. This action happens thanks to a chain of events inside your head.

Your eyes relay signals to the visual centers in the back of your brain. After those signals get processed, they travel along a pathway to another region, the premotor cortex, where the brain plans movements.

Now, imagine that you had a device implanted in your brain that could shortcut the pathway and “inject” information straight into your premotor cortex.

Continue reading “Scientists ‘Inject’ Information Into Monkeys’ Brains” →

It’s hard to see what’s so special about a scallop. It looks a lot like a clam, mussel or any other bivalve. Inside its hinged shell lurks a musclebound creature that’s best enjoyed seared in butter.

But there’s something more to this ubiquitous entree: the scallop sees its world with hundreds of eyes. Arrayed across the opening of its shell, the eyes glitter like an underwater necklace. Each sits at the tip of its own tentacle and can be extended beyond the rim of the shell.

While some invertebrate eyes can sense only light and dark, scientists have long suspected that scallops can make out images, perhaps even recognizing predators quickly enough to jet away to safety.

Continue reading “The Scallop Sees With Space-Age Eyes — Hundreds of Them” →

None of us was made from scratch. Every human being develops from the fusion of two cells, an egg and a sperm, that are the descendants of other cells. The lineage of cells that joins one generation to the next — called the germline — is, in a sense, immortal.

Biologists have puzzled over the resilience of the germline for 130 years, but the phenomenon is still deeply mysterious.

Over time, a cell’s proteins become deformed and clump together. When cells divide, they pass that damage to their descendants. Over millions of years, the germline ought to become too devastated to produce healthy new life.

Continue reading “Young Again: How One Cell Turns Back Time” →

In 2013, scientists discovered a new way to precisely edit genes — technology called Crispr that raised all sorts of enticing possibilities. Scientists wondered if it might be used to fix hereditary diseases, for example, or to develop new crops.

One of the more intriguing ideas came from Kevin M. Esvelt and his colleagues at Harvard University: Crispr, they suggested, could be used to save endangered wildlife from extinction by implanting a fertility-reducing gene in invasive animals — a so-called gene drive.

Continue reading “‘Gene Drives’ Are Too Risky for Field Trials, Scientists Say” →

For centuries, skin color has held powerful social meaning — a defining characteristic of race, and a starting point for racism.

“If you ask somebody on the street, ‘What are the main differences between races?,’ they’re going to say skin color,” said Sarah A. Tishkoff, a geneticist at the University of Pennsylvania.

On Thursday, Dr. Tishkoff and her colleagues showed this to be a profound error. In the journal Science, the researchers published the first large-scale study of the genetics of skin color in Africans.

Continue reading “Genes for Skin Color Rebut Dated Notions of Race, Researchers Say” →