The Nutcracker Ballet, a Christmas classic based on a story by E.T.A Hoffman with a score by Pyotr Ylyich Tchaikovsky, has captivated audiences for generations with its dream sequences and beautifully choreographed imaginings. Dancing children and charming adults celebrate the joys of gifts. Mice parade charmingly and graceful rats dance in dramatic battle with animated toy soldiers and the toy Nutcracker magically transformed from wood to life. The king rat, of course, is a villain, and his legions are sometimes depicted on stage as cute, elegant or sinister, but always with human manor. The rat king, mortally wounded in battle, is carried away by his rat subjects. The ballet is on youtube here, and the Rat King dances here.
Artist Mihail Chemiakin re-imagined the Nutcracker Ballet for the Kirov Ballet,
and depicted the rats in his dreamy 18th century style.
Photo credit: Marie Antoinette's Gossip Guide to the 18th Century
That is considered anthropomorphism, but research on prosocial behavior among animals offers tantalizing clues to the wisdom in such tales. Scientists are finding animals and humans share more qualities than we knew. A study reported in the December 9 issue of Science suggests rats may have capacity to be surprisingly empathetic and self-sacrificing. "Jailbreak Rat: Selfless Rodents Spring Their Pals and Share Their Sweets," a Scientific American story by Ferris Jabr, describes the new research, conducted by neuroscientist Peggy Mason, of the University of Chicago, and her colleagues, on altruistic rat behavior. They placed pairs of rats in Plexiglas pens, where one rat was free to run around and the other was trapped in a cage in the middle of the pen. After a week of trial and error, 23 of the 30 free rats learned to open the cage and free their imprisoned peers. The rats did not try to open doors to cages that were empty or that contained toy rats, suggesting freeing peers was the genuine goal.
In another set of experiments, Mason gave them a tougher task. She placed the rats in a pen with two cages-one with an imprisoned rat, and one with a favorite chocolate treat. The free rats could easily have liberated the chocolate themselves before freeing their pal, or they might have been so distracted by the treat that they forgot their friend's plight. Not only did the rats free the imprisoned rat first, they shared the chocolate. "I was shocked," Mason said. The free rats removed the chocolate from the cage before eating and sharing it, and they sometimes placed the chocolate in front of their recently sprung peers as though delivering it.
In earlier work, psychologist Jeffrey Mogil and colleagues at McGill University had shown mice recognize pain of other mice, and spend more time with suffering cage mates. He is interested in Mason's work, and wants to do more research. Mogil and Mason both say the trapped rats squeaked their distress, which would stress any rodent in earshot, but Mason doesn't think the distress calls were frequent enough to motivate the rescues.
A Nature blog on the report says Daniel Povinelli, who heads the cognitive evolution group at the University of Louisiana at Fayetteville, thinks the research shows emotional contagion, but not necessarily empathy, which means putting oneself in someone else's shoes. The free rats may have been helping their jailed peers to alleviate their own distress, he says. Mogil says the findings offer robust evidence that the rats were actively prosocial, but he's not sure about their motives. Mason says the rats' behavior was one step up from emotional contagion. A rat's first response to stress is to freeze and not move, she explains, and these rats moved beyond that to help another individual.
Click here for a fascinating review of animal empathy research by two leaders in the field, Peggy Mason and Emory University primatologist Frans de Waal.