Effects of consanguinity, exposure to pregnant females, and stimulation from young on male gerbils' responses to pups

Abstract

In three experiments investigating variables affecting responses of male Mongolian gerbils to conspecific young, we compared the behavior directed towards pups of natural fathers, virgin foster fathers, and sexually experienced foster fathers (Experiment 1); males either previously exposed or not exposed to pregnant females (Experiment 2); and males provided or not provided with extra opportunities to huddle over pups (Experiment 3). We found no difference in responses to pups among natural fathers, virgin foster fathers, and foster fathers that had fathered litters. On the other hand, both a week of exposure to a pregnant female and opportunity to huddle over pups for an extra 15 min/day had significant effects on males' subsequent responses to conspecific young. We speculate on the reasons why a male's response to pups might be affected by his exposure to a pregnant female and stimuli from pups, but not by the probability that the pups were his own offspring.

Effects of siblings on reproductive maturation and infanticidal behavior in cooperatively breeding Mongolian gerbils

“…For the Parents + Pups and Parents Only conditions, one male and one female littermate were randomly selected as subjects at weaning age, at which time all other siblings were permanently removed from the family. Because cohabitation with a pregnant female may inhibit infanticide in male gerbils, independently of cohabitation with pups (Clark, Liu, & Galef, 2001; Elwood 1977), we allowed the parents in both of these conditions to continue breeding, but for the Parents Only condition we removed pups from the family before the focal male and female could interact with them. In both of these conditions, the male and female subjects remained with their parents continuously, except that several days before the anticipated date of the dam's next parturition (based on an interbirth interval of 24-26 days [Marston & Chang, 1965] and on weekly body-mass measures of dams), the focal male and female were removed from the parents' cage at approximately 1500 h and housed together in a separate cage until approximately 0900 h the next morning.…”

Parenting Behavior

“…320 Housing with a pregnant female promotes males' interest in pups, 319 making Mongolian gerbils similar to some laboratory mice and California mice. 320 Housing with a pregnant female promotes males' interest in pups, 319 making Mongolian gerbils similar to some laboratory mice and California mice.…”