Other research suggests that play helps youngsters burn off excess energy and weight, and stay cozily warm. Most animals that exhibit playful behavior are birds or mammals that live highly social lives. Play helps cement their relationships. But some observers believe insects and other invertebrates may play too. Play helps cement animal relationships.
Most modern scientists doubt that playing ants exist.
But more recently, researchers have suggested that octopuses might amuse themselves with games. In an unusual experiment, biologists Jennifer Mather of the University of Lethbridge in Alberta, Canada, and Roland Anderson of the Seattle Aquarium gave eight octopuses empty plastic pill bottles. Of course, it's hard to know if the animals were amused or just practicing some arcane prey-catching skill.