Temporal patterns of parturition in mammals in captivity.
Previous research indicates that many primate species are more likely to give birth at night than during the day. This study attempted to determine whether temporal patterns of birth are discernible in a number of non-primate mammals. In addition, it sought to relate time of birth to the sleep/wake cycle and to the level of predation on the species. Data were collected and analyzed on birth hours in 26 mammalian species from two Chicago area zoos . Although temporal patterns of parturition were discernible for many species, the hypothesis that most birth would occur during the restive phase was not supported. However, a significant positive correlation between level of predation and the likelihood that birth would occur during the restive phase was found (n = 0.40). These findings are discussed in terms of predator/prey interaction and the protection (or lack of protection) that restive birthing might afford the mother and offspring at this vulnerable time.
D000204:Activity Cycles; D000818:Animals; D000836:Animals, Zoo / Q000502:physiology*; D036861:Delivery, Obstetric; D005260:Female; D007743:Labor, Obstetric; D008322:Mammals; D011235:Predatory Behavior; D011247:Pregnancy; D013997:Time Factors