“…Analysis of spontaneous agonistic interactions and evaluation of wounds or barbering among cagemates has been conducted in group‐housed male mice, 16,27,28,30,33,38,39,46,69,71‐90 female mice, 16,38,39,86,91,92 male rats, 4,14,22‐24,31,32,34,93‐98 female rats, 14 male bank voles, 99 and female hamsters 100,101 . The majority of these studies observed strict linear dominance hierarchies in male mice, male rats, male voles, and female hamsters; whereas markedly less strict hierarchies—or no hierarchies at all—were observed among female mice and rats.…”