Known as the Star-nosed mole, it is one of the oddest looking mammals to roam the planet. That funny shaped nose is actually used for a very special skill: the ability to smell underwater. With no vision, this semi-aquatic mammal needs an advantage when it comes to finding his food.
Sniffing brings in molecules in the air around our nose, this allows animals and humans to smell scents. Try this underwater though and you will find yourself quickly drowning, the star-nosed mole though has found a way to beat the odds and safely sniff in the water.
Its snout is a ring of 22 little tentacles, that are filled with touch sensors, with this super nose the mole looks for worms to eat. But the star-nosed mole does not just dig underground, they are also very capable swimmers looking for food in lakes and streams. Once underwater their nose starts to be used in a very different way.
Kenneth Catania from Vanderbilt University in Tennessee, took a very high-speed video of a mole while hunting underwater. He noticed that the mole was breathing as quickly as a rat, blowing out a tremendous amount of bubbles. He made up a theory that it was quickly blowing out bubbles and re-inhaling them. This would allow the mole to follow airborne scents even when underwater.
To test his theory he placed a food scent that led to food but kept the trail covered by a steel grid. When the moles could blow bubbles through the steel grid, they could very easily find the food at an accuracy of 85%. However, when he made the grid too small to allow their bubbles to pass through, then the mole’s accuracy at locating the food dropped suddenly by 50%.
A very cool skill for the animal that already holds the Guinness book of world record for being the fastest eater. It is not alone though, with this skill, other semi-aquatic animals like the water shrew are also able to sniff underwater.