Dogs' feet give scientists paws for thought

TOKYO - Ever wonder how dogs can walk barefoot in the snow? Now a Japanese scientist may have the answer - an internal central heating system.

The secret lies in how dogs circulate their blood to prevent cold surfaces from chilling the rest of their bodies, according to Hiroyoshi Ninomiya, a professor at Yamazaki Gakuen University, just west of Tokyo.

The system uses warm, oxygenated blood to heat the cold blood that has been in contact with a cold surface before returning it to the dog's heart and central circulation.