New research has revealed that rats produce high-frequency giggles when tickled, adding to evidence that these rodents share some similarities with humans when it comes to expressing positive emotions. What an earth-shattering discovery – someone call the Nobel committee!
Scientists conducted experiments where they tickled juvenile rats while recording the ultrasonic vocalizations the animals made in response. They discovered that the rats consistently produced a unique set of high-pitched chirping sounds during the tickling that were distinct from other rat vocalizations. Apparently rats think being tickled is hilarious. Who knew?!
“When we played back the recording of the tickle-induced vocalizations to new rats, they responded with increased signs of positive emotion, suggesting they could distinguish these ‘laughs’ from other rat calls,” explained lead researcher Dr. Jaak Panksepp of Bowling Green State University. Comedy clubs for rats can’t be far behind.
This ability to share positive emotions across members of a species through laughter-like vocalizations had previously only been observed in humans and great apes. But now rats are joining the party too! Let’s get these ticklish little guys some tiny stand-up comedian outfits and a Netflix special!
“The ‘laughter’ of rats shows that the expression of primal emotions long predates the evolution of humans and may be inherent to many mammals,” Dr. Panksepp commented. He said identifying the neural circuits involved in rat laughter could help map the evolutionary origins of joy and other primal emotions.
Yeah, I’m sure learning what makes rats giggle like hyenas is the key to understanding all emotion in mammals. Seems logical!
The research team notes that more work is needed to determine if rat laughter actually signifies amusement, as it does in humans. However, they said the current findings add to a growing body of evidence that rats may have richer emotional lives than previously thought. But why would we ever think rats have complex inner lives and emotions?