Tiny “fingers” may also help polar bears get a grip.
Just like the rubbery nubs on the underside of child socks, microstructures on the bears’ paw pads supply some further friction, scientists report November 1 within the Journal of the Royal Society Interface. The pad protrusions might preserve polar bears from slipping on snow, says Ali Dhinojwala, a polymer scientist on the College of Akron in Ohio who has additionally studied the sticking energy of gecko ft (SN: 8/9/05).
Nathaniel Orndorf, a supplies scientist at Akron who focuses on ice, adhesion and friction, was within the work Dhinojwala’s lab did on geckos, however “we will’t actually put geckos on the ice,” he says. So he turned to polar bears.
Orndorf teamed up with Dhinojwala and Austin Garner, an animal biologist now at Syracuse College in New York, and in contrast the paws of polar bears, brown bears, American black bears and a solar bear. All however the solar bear had paw pad bumps. However the polar bears’ bumps seemed slightly totally different. For a given diameter, their bumps are usually taller, the crew discovered. That further peak interprets to extra traction on lab-made snow, experiments with 3-D printed fashions of the bumps recommend.
Till now, scientists didn’t know that bump form may make the distinction between gripping and slipping, Dhinojwala says.
Polar bear paw pads are additionally ringed with fur and are smaller than these of different bears, the crew stories, variations which may let the Arctic animals preserve physique warmth as they trod upon ice. Smaller pads usually imply much less actual property for grabbing the bottom. So extra-grippy pads may assist polar bears take advantage of what they’ve bought, Orndorf says.
Together with bumpy pads, the crew hopes to check polar bears’ fuzzy paws and brief claws, which could additionally give the animals a nonslip grip.
