The use of tools is not exclusive to the human being. Some animals also have their own gear. For example, among thebottlenose dolphinsfrom Shark Bay, Australia, it is common to wearcone-shaped sponges on the snout. But for what? That is the question that a team of American biologists tries to answer in the latest issue of the magazine.PLoS ONE.
Observing the behavior of more than 40 dolphins, mostly female, the scientists concluded that these marine mammals use sponges plucked from the ocean floor to protect their snouts whileremove sand from the ocean floor in search of prey, similar to a gardener who wears gloves to protect his hands. Once they find their loot, they temporarily release the sponge so they can eat it. In most cases the hunted fish belongs to the speciesParapercis clathrata, which is perfectly camouflaged in the sand and is practically invisible if the dolphin technique is not used.
On the other hand, the researchers assure that this use of the sponges seems to beculturally transmitted from generation to generation, mainly from mothers to daughters. Comparing the lifestyle of sponge-using dolphins with that of those who do not use them, they have found that the former tend to occupydeep water areas, they travel great distances and spend many hours in the most absoluteloneliness. ? While the females that use sponges are alone 80% of the time, those that do not use this tool in the same waters barely spend 30% of the time without company ,? explain the scientists inPLoS ONE. However, this habit does not have negative consequences when it comes to reproducing.
Specializing in sponge hunting, they conclude, implies a change in lifestyle for dolphins, with social and ecological implications (change of habitat).
