MOROGORO, Tanzania — Often dismissed as pests, rats have long been misunderstood. But the African giant pouched rat (Cricetomys gambianus), the world’s longest, is challenging that perception.

New research on the feeding habits of the desert rat-kangaroo could help locate the possibly extinct species, with ...

Brain cells (magenta) in the reward center of a rat’s brain release dopamine in response to opioids. According to a new study by WashU Medicine researchers, male and female rats with a chronic pain ...