Prairie voles experience an explosion of dopamine, the pleasure hormone, when they are reunited with their partner. After a period of separation, the effect diminishes.

Prairie voles are one of the few monogamous mammal species. The study could be relevant to understanding how people overcome grief, especially in the case of patients with prolonged grief disorder, Dr. Zoe Donaldson says. The study was published this month in the journal Current Biology, which is published by the University of Colorado Boulder.