Air way

时间:2019-03-08 08:19:28166网络整理admin

A MOUSE which is too small to work its lungs when it is born is the first mammal known to breathe through its skin. The Julia Creek dunnart, a rare Australian marsupial, is only 4 millimetres long when it crawls from its mother’s womb to her pouch. Its lungs are fully formed, but its muscles are too week to inflate them, says Jacopo Mortola, a physiologist at McGill University in Montreal. “Air gets in only by chance,” he says. Mortola measured the oxygen uptake of baby dunnarts in a colony kept at La Trobe University in Melbourne. He found that their skin absorbs 50 times as much oxygen as their lungs. These gradually take over to be fully functional when the mouse leaves the pouch (Nature, vol 397,