Animals that can use stones as tools.

Sea otters, seals and sea otters use tools to get food.

Sea otters have a layer of skin under their arms. They usually hide a stone in their skin and use it as a hammer or chopping block to pry open the shell and get the food inside. The use of tools by animals is the result of evolution, and some animals have reached a high degree of specialization (instinct). For example, woodpeckers in Galapagos hold cactus thorns or branches in their mouths to detect insects in cracks in bark.

Sea otters also use stones as tools. The use of animal tools is mostly studied by primates. For example, primates stack boxes to get high food, and break the hard shell of fruit food with stones. There are generally two ways to use animal learning tools, one is through observation and the other is through trial and error.