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There are always "surprises" emerging from studies of the cognitive, emotional, and moral lives of nonhuman animals (animals) and among the discoveries that received a good deal of attention was detailed research published in prestigious peer-reviewed journals that showed that chickens, mice, and rats displayed empathy (please see "Empathic Rats and Ravishing Ravens" for details and pertinent references). In that essay I noted that over the past few years we've learned much about the moral lives of animals ("wild justice"; see also and). Detailed studies have shown that mice and chickens display empathy and now we know rats do too.
A study published in 2011 conducted by Inbal Ben-Ami, Jean Decety, and Peggy Mason working at the University of Chicago provided the first evidence of empathy-driven behavior in rodents. Appearing in the prestigious journal Science, the results of this landmark study showed that untrained laboratory rats will free restrained companions and this helping is triggered by empathy (Ben-Ami Bartal, I., Decety, J., & Mason, P. 2011. Empathy and pro-social behavior in rats. Science 334, 1427-1430). They'll even free other rats rather than selfishly feast on chocolate. Researcher Peggy Mason noted, "That was very compelling…It said to us that essentially helping their cagemate is on a par with chocolate. He can hog the entire chocolate stash if he wanted to, and he does not. We were shocked." In response to these studies I've received comments such as, "Oh really, I didn't know that" and "Wow, who would have thought chickens, mice, and rats would display empathy for others?"
"Pro-social behavior in rats is modulated by social experience"
Just today another fascinating study called "Pro-social behavior in rats is modulated by social experience" was published in the open access journal eLife. Some of the same researchers from the earlier study of rats were involved in this landmark project. A press release about this study notes, among other things, "that social experiences, not genetics or kin selection, determine whether an individual will help strangers out of empathy. The importance of social experience extends even to rats of the same strain—a rat fostered and raised with a strain different than itself will not help strangers of its own kind." And, according to the University of Chicago's Inbal Bartal the lead author of the study "Pro-social behavior appears to be determined only by social experience…It takes diverse social interactions during development or adulthood to expand helping behavior to more groups of unfamiliar individuals. Even in humans, studies have shown that exposure to diverse environments reduces social bias and increases pro-social behavior."
In addition to this fascinating and groundbreaking study another paper recently appeared called "Toward a cross-species understanding of empathy" by renowned researcher and author of Affective Neuroscience Jaak Panksepp and Jules B. Panksepp (a PDF of this paper is also available here).
So, what are we going to do with what we know? Nothing so far
We can only hope these findings will be used to protect rats and other rodents from being used in horrific invasive research. Although it's been known for more than five years that mice display empathy this has not been factored into a revision of the Federal Animal Welfare Act in the United States. Rodents and many millions of other animals who comprise more than 99% of the animals used in invasive research can still be greatly harmed or killed "in the name of science." Indeed, the Animal Welfare Act does not consider them to be "animals". Only about 1 percent of animals used in research in the United States are protected by legislation and the legislation is sometimes amended in nonsensical ways to accommodate the "needs" of researchers.
Birds, rats, and mice are not animals: Say what?
The desperation of science to rob animals of their sentience produces distortions that open the door for egregious and reprehensible abuse. For instance, here is a quote from the federal register: "We are amending the Animal Welfare Act (AWA) regulations to reflect an amendment to the Act's definition of the term animal. The Farm Security and Rural Investment Act of 2002 amended the definition of animal to specifically exclude birds, rats of the genus Rattus, and mice of the genus Mus, bred for use in research" (Vol. 69, no. 108, 4 June 2004). It may surprise you to learn that birds, rats, and mice are no longer considered animals, but that is the sort of logic that epitomizes federal legislators. Researchers are not allowed to abuse animals, so the definition of animal is simply revised until it refers only to creatures researchers don't need. Garet Lahvis, a behavioural neuroscientist at Oregon Health & Science University in Portland, correctly notes, "We study animals to see what makes us uniquely human, but the findings of empathy in animals often force uncomfortable questions about how humans treat animals."
Stay tuned for more on the fascinating lives of other animals. It's essential that we use what we know about them on their behalf and not granting birds and rodents much more protection is inexcusable.
Marc Bekoff's latest books are Jasper's Story: Saving Moon Bears (with Jill Robinson; see also), Ignoring Nature No More: The Case for Compassionate Conservation (see also), and Why Dogs Hump and Bees Get Depressed (see also).
