The first demonstration of empathy driven helping behaviour in rodents. This paper now serves as the basis for all current experiments in the laboratory.
Building upon the work of the last paper, this one delves further into the idea of pro-social behavior. In this case, two different strains of rats were used. Rats that would only consistently open for rats of the same strain they were raised in, even if they weren't born of the same strain.
This review describes a variety of perspectives on empathy from the point of view of biology, anthropology, medicine, and psychology.