According to scientists, Sea otters may have been using stone tools for thousands or even millions of years. It appears that otters learned how to use tools long before other marine mammals. Sea otters are generally seen floating on their backs, using rocks to break open shellfish for food. A genetic study of more than 100 wild sea otters living off the Californian coast suggests their ancestors living millions of years ago showed this behavior. In Australia, Dolphins have been seen to use sponges to protect their noses when scouting for fish on the sea floor. However, this appears to be a relatively new invention, happening less than 200 years ago.
Dr. Katherine Ralls of the Smithsonian Conservation Biology Institute in Washington, US, said they were surprised to find sea otters using tools were not from the same family group, advising the behavior originated in the ancestors of modern sea otters. She said, “It’s older in sea otters.” “They are very smart; they’ll use rocks as hammers and as anvils.”
They wrote in the Royal Society journal Biology Letters that, “Orphaned otter pups raised in captivity exhibit rudimentary pounding behavior without past experience or training, and wild pups develop tool-use behavior before weaning regardless of their mother’s diet type.” The sea otter is found along the coasts of the Pacific Ocean in Asia and North America. They were once hunted for their fur almost to extinction. Early in the 20th Century, only 1,000 to 2,000 animals remained. Sea otters are now protected by law.
The scientists plan to study fossil remains of sea otters to affirm when the behavior emerged. They think depressions in the chests of some modern otters thought to be from holding rocks on their chests might be present in fossil specimens. Tool use has been observed in a range of animals, including primates and crows. Dr. Christian Rutz, an evolutionary ecologist at the University of St Andrews, who studies tool use in New Caledonian crows and Hawaiian crows said, “Sea otters provide a fascinating opportunity to investigate how genetic predispositions, environmental conditions and learning contribute to a species’ capacity to use foraging tools.”