Monkeys provide models of child abuse

Some parents neglect or physically harm their young. Their abuse of helpless offspring mirrors the practices of other adults in their families, reflects hostile or emotionally ambivalent parenting styles, and intensifies in response to various types of social stress.

 Such parents are more than dangerous -- they're monkeys. Evidence of links between maltreatment of their young among monkeys and people suggests that nonhuman primates hold great promise as models for investigating this poorly understood behavior, say two psychologists who study monkey families. Their review of research in this area appears in the May Psychological Bulletin.

"Promising animal models of [child maltreatment] are already available, and new ones can and must be developed," hold Dario Maestripieri of Yerkes Regional Primate Research Center in Lawrenceville, Ga., and Kelly A. Carroll of Berry College in Rome, Ga.

 Records extending over 35 years at Yerkes indicate that, in both pigtail macaques and sooty mangabeys, 5 percent of infants are abandoned by their mothers and another 5 percent to 10 percent suffer severe physical abuse from their mothers, the scientists report. These conservative estimates roughly match neglect and abuse rates in human populations, they say.

 In group-living monkeys such as macaques and mangabeys, neglect and abuse rarely occur together and may represent separate phenomena, Maestripieri and Carroll argue. Neglect typically takes place among young, inexperienced mothers that abandon only one child, usually the first-born, as an infant. In contrast, abusive mothers span a wide age range and frequently harm successive offspring. Abusive monkey mothers, which also tend to exhibit overprotectiveness and rejection, invest considerable time and energy in their infants. This parenting pattern often runs in families, report Maestripieri and Carroll.

 Social stress, such as experiencing low status, clearly evokes infant abuse in pigtail macaques, they add. This species, known for its sensitivity to environmental changes, may provide a good model for investigating the effects of social stress on abusive human parents, the researchers propose.

 Monkeys might help illuminate human child neglect, but the diverse forms and causes of child abuse in human societies probably do not have counterparts in nonhuman primates, argues primatologist William A. Mason of the University of California, Davis in an accompanying comment.