Archivo: Science

Most of us think of Europe as the ancestral home of white people. But a new study shows that pale skin, as well as other traits such as tallness and the ability to digest milk as adults, arrived in most of the continent relatively recently.

Beans are a staple for hundreds of millions of people, mostly in Latin America and Africa. But these legumes, which originated in cool highlands, are particularly sensitive to excessive warmth—so much so that by 2050, climate change might cut in half the amount of land suitable for growing them. Plant breeders with the International Center for Tropical Agriculture (CIAT) in Cali, Colombia, are aiming to fix that problem. Using samples from gene banks, they recently identified 30 varieties of common beans that can stand up to temperatures that would otherwise cause the crops to fail.

What little ice remains on Mercury and Mars is mostly confined to the planets’ poles, as one would expect, because the sun shines the least in those regions. Not so on the moon. Much of the moon’s ice, which lurks beneath the surface, is found in an area 5.5° away from the north pole and in a matching region 5.5° from the south pole, scientists announced here this week at the Lunar and Planetary Science Conference. The data suggest that in the past, the moon’s axis of rotation—and hence its poles—shifted.

Here’s a new way to search for life on alien worlds: Look for the light it reflects into space. To prepare for such a search, scientists have made a library of life’s colors, cataloging the spectra, or wavelengths of light, reflected by 137 types of microorganisms.

To the untrained eye, real animal sponges may seem as boring as synthetic kitchen sponges. But the evolution of these highly porous creatures has long been a mystery, with major implications for the early evolution of animals

Killer whales wouldn’t get far without their old ladies. A 9-year study of orcas summering off the southern tip of Vancouver Island in the Pacific Northwest finds that menopausal females usually lead their families to find salmon, particularly when the fish are scarce. Older females’ years of foraging experience may help their clans survive in years of famine, an evolutionary benefit that could explain why—like humans—female orcas live for decades past their reproductive prime.

For years some physicists have been hoping to crack the mystery of high-temperature superconductivity—the ability of some complex materials to carry electricity without resistance at temperatures high above absolute zero—by simulating crystals with patterns of laser light and individual atoms. Now, a team has taken—almost—the next-to-last step in such “optical lattice” simulation by reproducing the pattern of magnetism seen in high-temperature superconductors from which the resistance-free flow of electricity emerges.

A team of astronomers was stunned to discover what is, in galactic terms, a monstrous baby: a gigantic black hole of 12 billion solar masses in a barely newborn galaxy, just 875 million years after the big bang.

It may sound radical, but it works: Eating peanuts slashes the chance of a peanut allergy, at least in children at high risk of developing one, a much-anticipated study finds. The results are likely to catapult a long-standing theory—that ingesting potential food allergens is a way to prevent allergies—into mainstream medicine.

Our DNA may encode all the instructions needed to build the human body and keep it running, but each of our cells must follow just a subset of those instructions in order for the body to work properly. Thanks to the $300 million, National Institutes of Health (NIH) Roadmap Epigenomics Project, researchers have now identified most of the chemical tags on DNA and its associated proteins that influence gene function and help define more than 100 different kinds of human cells. The knowledge of these so-called epigenetic modifications has already led to new insights into Alzheimer’s disease, cancer, and development.