Swift kick from a supernova could knock a black hole askew

Gravitational waves are providing new hints about how black holes get their kicks. The Advanced Laser Interferometer Gravitational-Wave Observatory’s detection of spacetime ripples from two merging black holes on December 26, 2015, indicated that one black hole was spinning like a tilted top as it orbited with its companion (SN: 7/9/16, p. 8). That off-kilter […]

Ancient DNA shakes up the elephant family tree

Fossil DNA may be rewriting the history of elephant evolution. The first genetic analysis of DNA from fossils of straight-tusked elephants reveals that the extinct animals most closely resembled modern African forest elephants. This suggests that straight-tusked elephants were part of the African, not Asian, elephant lineage, scientists report online June 6 in eLife. Straight-tusked […]

When should babies sleep in their own rooms?

When we brought our first baby home from the hospital, our pediatrician advised us to have her sleep in our room. We put our tiny new roommate in a crib near our bed (though other containers that were flat, firm and free of blankets, pillows or stuffed animals would have worked, too). The advice aims […]

The southern drawl gets deconstructed

BOSTON — Some aspects of speech are as Southern as pecan pie. Consider the vowel shift that makes the word pie sound more like “pah.” While that pronunciation is found from Florida to Texas, a new study reveals a surprising diversity in Southern vowel pronunciation that’s linked to a speaker’s age, social class, gender, race […]

Slug slime inspires a new type of surgical glue

For a glue that holds up inside the body, turn to the humble slug, Arion subfuscus. A new super-sticky material mimics slug slime’s ability to stick on slick wet surfaces and could lead to more effective medical adhesives. The material has two parts: a sticky layer that attaches to a surface, and a shock-absorbing layer […]

Why midsize animals are the fastest

Speed has its limits — on the open road and the Serengeti. Midsize animals tend to be the speedsters, even though, in theory, the biggest animals should be the fastest. A new analysis that relates speed and body size in 474 species shows that the pattern holds for animals whether they run, fly or swim […]

Polluted water: It’s where sea snakes wear black

Maybe it’s more than reptile fashion. The high percentage of citified sea snakes wearing black might be a sign that pollution is an evolutionary force. Off the coasts of Australia and New Caledonia, some turtle-headed sea snakes (Emydocephalus annulatus) sport pale bands on their dark skins. Others go all black. In 15 places surveyed, the […]

Some secrets of China’s terra-cotta army are baked in the clay

China’s first emperor broke the mold when he had himself buried with a terra-cotta army. Now insight into the careful crafting of those soldiers is coming from the clays used to build them. Custom clay pastes were mixed at a clay-making center and then distributed to specialized workshops that cranked out thousands of the life-size […]

These transparent fish turn rainbow with white light. Now, we know why

The ghost catfish transforms from glassy to glam when white light passes through its mostly transparent body. Now, scientists know why. The fish’s iridescence comes from light bending as it travels through microscopic striped structures in the animal’s muscles, researchers report March 13 in the Proceedings of the National Academy of Sciences. Many fishes with […]

Ancient DNA suggests people settled South America in at least 3 waves

DNA from a 9,000-year-old baby tooth from Alaska, the oldest natural mummy in North America and remains of ancient Brazilians is helping researchers trace the steps of ancient people as they settled the Americas. Two new studies give a more detailed and complicated picture of the peopling of the Americas than ever before presented. People […]