抖阴ap

New research into the underwater olfactory abilities of the star-nosed mole and the water shrew has concluded that these mammals actually can smell under water. Even more remarkable is how: by blowing air bubbles out their nostrils and then sucking them back in.

After noticing the bubbles, researcher Kenneth Catania set up a camera beneath the glass tank and began filming. He found that the semiaquatic animals exhaled and inhaled the bubbles five to 10 times a second, about the same rate as the sniffing behavior of a similarly sized land mammal, such as a rat or a mouse. Catania placed a number of objects – some edible, some not – on the tank floor and watched the mole. He found that when the animals approached one of the objects, they would blow bubbles that made contact with the objects and then were sucked back into the nostrils.

The star-nosed moles were further tested in an underwater course that had a trail of fish or earthworm scent. Since the moles can use the ultra-sensitive star appendages that surround their noses almost like fingers, a thin grid was placed between the animals and the trail to make sure they were only smelling the scent. Five moles were able to follow the earthworm smell accurately 75 to 100 percent of the time, and two moles followed the fish smell 85 to 100 percent of the time. When an even finer grid was used – one that interrupted the mole’s bubble-smelling system – the rate of success fell to simple chance.