On a table in Masons University of Chicago lab sits a plexiglass box about two feet square. Inside is a white Sprague-Dawley rat, a strain bred for laboratory study, and a plexiglass canister holding a black-and-white Long-Evans rat.

The trapped Long-Evans is clearly agitated. The white rat is too. Instinctively, she wants to stay in the corner; rats avoid open spaces, and navigate by touch, which is why you often see them scurrying along walls. Yet she rushes again and again to the canister, sniffing at the rat inside, nosing the glass, nudging the door. Eventually, she opens it, freeing the rat. They rub together.

At a purely descriptive level, you could say one rat helped another. Why that happened is the question. According to Peggy Mason and collaborator Inbal Ben-Ami Bartal, the free rat appears to empathize with her trapped comrade. She recognized the rats distress, grew distressed herself and wanted to help. This appears to be a powerful impulse in rats. In tests of whether rats would rather eat than help another rat, the researchers found empathys pull to be as strong as their desire for chocolate and rats do love their chocolate.

The two researchers first claimed rats might feel empathy in a high-profile 2011 Science paper describing rats freeing their cagemates, rats they had been cohabitating with. They expand on those findings in the latest study, which describes rats helping strangers. Its a radical, even controversial, claim. Some scientists recognize that chimpanzees, a few cetaceans and perhaps elephants could be empathic, but few have ascribed that trait to rats. If R. norvegicus can be empathic, that fundamentally human trait might in fact be ubiquitous.

Were in a period of transition with respect to how we think about animals, said environmental philosopher Eileen Crist. After centuries of seeing the animal kingdom as a hierarchy with humans on top, of treating animals as purely instinct-driven biological machines, cognitive ethology is opening up a new terrain. Knowledge itself is fluid and changing right nowand empathy investigations are very much a part of that.

Those whove had pet rats may not be surprised by reports of their empathy, nor will readers of naturalists texts from the 19th and early 20th centuries. (Witmer Stone and William Everett Cram, for example, wrote of rats in 1902s American Animals, Careful witnesses have always given them credit for looking after any helpless member of their family.) But informal observations carry little scientific weight, and researchers are reluctant to describe what animals might think and feel. After all, animals cant tell us, and we cant read their minds.

Theres some historical baggage, too. Twentieth-century study of animal behavior was famously inhospitable to the idea that animals feel much of anything. B.F. Skinner, the father of modern animal behavioral science, called emotions an excellent example of the fictional causes to which we commonly attribute behavior. Such views have largely fallen from favor, but science has been slow to embrace Charles Darwins essential point: that humans and other animals necessarily share not only anatomical roots, but neurological origins.

Claiming empathy for rats isnt easy, and one criticism of Mason and Ben-Amis interpretation is that a far simpler phenomenon called emotional contagion could explain their rats helpfulness. In other words, when one rat becomes distressed, that distress spreads to othersbut they dont necessarily feel for the first and translate that feeling into intention.

As Oxford University zoologist Alex Kacelnik and colleagues noted in a 2012 Biology Letters reflection on empathy research, some ants display helping behaviors similar to Mason and Ben-Ami Bartals rats. Any solid evidence for empathy in non-humans would be a notable advance, they wrote, but, in our view, it remains unproven outside humans.

Other researchers defended the possibility of rat empathy. Ants are not rats, quipped Frans de Waal, an Emory University ethologist who has written extensively about empathy, on Facebook. It would be totally surprising, from a Darwinian perspective, if humans had empathy and other mammals totally lacked it. As for Mason and Ben-Ami Bartal, theyve downplayed the empathy interpretation in their latest work, restricting it to speculative discussion.

View post:
The Intriguing New Science That Could Change Your Mind About Rats