Here’s how polar bears might get traction on snow

Tiny “fingers” can help polar bears get a grip. Like the rubbery nubs on the bottom of baby socks, microstructures on the bears’ paw pads offer some extra friction, scientists report November 1 in the Journal of the Royal Society Interface. The pad protrusions may keep polar bears from slipping on snow, says Ali Dhinojwala, ... Read more

Common, cheap ingredients can break down some ‘forever chemicals’

There’s a new way to rip apart harmful “forever chemicals,” scientists say. Perfluoroalkyl and polyfluoroalkyl substances, also known as PFAS, are found in nonstick pans, water-repellent fabrics and food packaging and they are pervasive throughout the environment. They’re nicknamed forever chemicals for their ability to stick around and not break down. In part, that’s because ... Read more

Why mosquitoes are especially good at smelling you

Some mosquitoes have a near-foolproof thirst for human blood. Previous attempts to prevent the insects from tracking people down by blocking part of mosquitoes’ ability to smell have failed. A new study hints it’s because the bloodsuckers have built-in workarounds to ensure they can always smell us. For most animals, individual nerve cells in the ... Read more

Oort cloud comets may spin themselves to death

Comets from the solar system’s deep freezer often don’t survive their first encounter with the sun. Now one scientist thinks he knows why: Solar warmth makes some of the cosmic snowballs spin so fast, they fall apart. This suggestion could help solve a decades-old mystery about what destroys many “long-period” comets, astronomer David Jewitt reports ... Read more