Top stories: A deadly plague epidemic, the evolution of skin color, and thrice-domesticated rice

Deadly plague epidemic rages in Madagascar

An epidemic of the deadliest form of plague, pneumonic, has hit major cities and towns in Madagascar and is spreading fast. As of 7 October, the Madagascar Health Ministry reported that 343 people had been infected and 42 died, and numbers are rising rapidly. A massive response is underway, and the World Health Organization is on high alert. This poor island nation is regularly hit by plague outbreaks, but they are typically the relatively less dangerous bubonic form, transmitted from rats to humans by fleas, and occur largely in remote areas.

New gene variants reveal the evolution of human skin color

Most people associate Africans with dark skin. But different groups of people in Africa have almost every skin color on the planet, from deepest black in the Dinka of South Sudan to beige in the San of South Africa. Now, researchers have traced the evolution of a handful of new gene variants responsible for this palette of tones. While the dark skin of some Pacific Islanders can be traced to Africa, gene variants from Eurasia also seem to have made their way back to Africa. And surprisingly, some of the mutations responsible for lighter skin in Europeans turn out to have an ancient African origin.

Watch the human genome fold itself in four dimensions 

Each human cell nucleus is packed with 2 meters of DNA wrapped around 46 chromosomes like a jumble of spaghetti. These “noodles” are in constant motion as they adjust to what the cell needs to do, and these adjustments bring certain genes into contact so they can work together. Now, researchers have visualized this dance at 20-minute intervals, so that they get a 4D rendering: They can see how this 3D structure changes over time. In doing so they have demonstrated how one protein helps orchestrate these movements.

Astronomers say they’ve found many of the universe’s missing atoms

If you get frustrated when you can't find your keys, imagine how astronomers feel: For years, they’ve been unable to locate roughly half the atoms they think the universe must contain. Now, researchers have tracked down a lot of that missing matter using radiation from the early universe that acts like a laser illuminating billowing smoke. The finding helps understand how the universe has evolved over time.

Rice so nice it was domesticated thrice

Rice is unique among wild plants for having been domesticated independently on three continents: Asia, Africa, and now South America, researchers have discovered. The New World variety, tamed about 4000 years ago to produce larger grains, apparently was abandoned after Europeans arrived. But its genetic legacy could potentially help improve Oryza sativa, the Asian rice species that is now a dietary staple for half the world’s population.

Scientists uncover source of Old Faithful’s hot water supply 

If only humanmade plumbing were as reliable as Old Faithful’s. Every 90 minutes or so, Yellowstone National Park’s iconic geyser spews water and steam 40 meters high, on a schedule so precise that tourists know when to gather to watch the show. Now, by listening for seismic waves from the water and steam percolating through the ground near Old Faithful, geophysicists have caught a glimpse of the subsurface reservoir that supplies the clockwork gusher.