It's no joke. For the first time, a bird species has been found to exhibit a behavior similar to what is known as "contagious laughter" in humans.
Keas -- parrots native to New Zealand that can grow to the size of a cat -- have always been known as particularly playful. Researchers recently learned that when exposed to a specific warble, they get positively frolicsome -- and the behavior is catching.
A research team led by Raoul Schwing of the University of Veterinary Medicine in Vienna, Austria, played a series of recordings to some wild keas in New Zealand. Besides the warble, the sounds included a whistle, a screech, a bland tone, and a warning call from a robin. Only the warble produced the playfulness, which included aerial acrobatics, tossing objects back and forth, and exchanging foot slaps.
Schwing said the discovery suggests a closer link between birds and people than previously known. "The only other animals to show this contagion effect are chimpanzees and rats, both very or relatively close in evolutionary terms,” Schwing said. “Our finding further bridges the perceived gap between humans and [other] animals, and shows that it also happens in birds, which are very distantly related.”
Key kea facts:
- While keas don't "talk" like some other parrots, they are considered very intelligent, perhaps equivalent to a 4-year-old child.
- Keas have been labeled unintentional killers, as they sometimes tear fat from the backs of horses, dogs, and rabbits for food; those animals sometimes die from an ensuing infection.
- In the wild, only about a quarter of all kea chicks will survive a year after hatching.