Dolphins play at least 317 different games
The captive dolphins "produced 317 distinct forms of play behavior during the five years that they were observed," they wrote.Link
One calf became adept at "blowing bubbles while swimming upside-down near the bottom of the pool and then chasing and biting each bubble before it reached the surface," the researchers continued. "She then began to release bubbles while swimming closer and closer to the surface, eventually being so close that she could not catch a single bubble."
"During all of this, the number of bubbles released was varied, the end result being that the dolphin learned to produce different numbers of bubbles from different depths, the apparent goal being to catch the last bubble right before it reached the surface of the water."
"She also modified her swimming style while releasing bubbles, one variation involving a fast spin-swim. This made it more difficult for her to catch all of the bubbles she released, but she persisted in this behavior until she was able to almost all of the bubbles she released. Curiously, the dolphin never released three or fewer bubbles, a number which she was able to catch and bite following the spin-swim release."
The dolphin may have been keeping her play interesting by blowing more bubbles than she could easily catch and bite, the researchers wrote.