A group of dolphins living off the coast of Australia apparently teach their offspring to protect their snouts with sponges while foraging for food in the sea floor. Researchers say it appears to be a cultural behavior passed on from mother to daughter, a first for animals of this type, although such learning has been seen in other species. The dolphins, living in Shark Bay, Western Australia, use conically shaped whole sponges that they tear off the bottom, said Michael Kruetzen, lead author of a report on the dolphins in Tuesday’s issue of Proceedings of the National Academy of Science.
“Cultural evolution, including tool use, is not only found in humans and our closest relatives, the primates, but also in animals that are evolutionally quite distant from us. This convergent evolution is what is so fascinating,” said Kruetzen. Researchers suspect the sponges help the foraging dolphins avoid getting stung by stonefish and other critters that hide in the sandy sea bottom, just as a gardener might wear gloves to protect the hands.
[The photo was taken by Dr. Janet Mann. The dolphin’s name is Dodger and she was taught to sponge by her mother, Demi. Demi’s mom, Half fluke, was also a sponger.]