Effects of environmental stressors on deep body temperature and activity levels in silver fox vixens (Vulpes vulpes)

The present study was performed to investigate the effects of 14 different environmental stimuli on stress-induced hyperthermia (SIH). and levels of locomotor activity in six (three infanticidal, three non-infanticidal. 2.5-year-old silver fox vixens. The effects of contact with humans) six experiments; handling for 5 min, handling of neighbouring animal for 5 min, presence of one […]

Social behavior of Matschie’s tree kangaroos (Dendrolagus matschiei) and its implications for captive management

Abstract 10.1002/zoo.1430100207.abs Social behavior was studied in four (one male and three females) adult, captivebred Matschie’s tree kangaroos (Dendrolagus matschiei) over a 124 day span in a large, naturalistic exhibit at the Woodland Park Zoological Gardens, Seattle, WA. A relatively high rate of social interaction occurred (15.2 per hour), over half of which consisted of […]

Social suppression of female reproductive maturation and infanticidal behavior in cooperatively breeding Mongolian gerbils

In several cooperatively breeding species, reproductively suppressed, nonbreeding females are attracted to infants and routinely provide alloparental care, while breeding females may attack or kill other females’ infants. The mechanisms underlying the transition from alloparental to infanticidal behavior are unknown. In this study, we tested the hypothesis that this transition is associated with cessation of […]

Diminished maternal responsiveness during pregnancy in multiparous female common marmosets

Common marmoset monkeys (Callithrix jacchus) live in small groups in which, usually, only a single female breeds and all group members provide infant care. When two females breed concurrently, however, they may commonly kill one another’s infants, especially during the peripartum period. To investigate the mechanisms underlying infanticide by breeding females, we characterized responses of […]

Infanticide risk and infant defence in multi-male free-ranging sooty mangabeys, Cercocebus atys

For years, infanticide by males was thought to be unlikely in multi-male primate species. Recent studies have, however, presented evidence of infanticide in such species and a recent model by Broom and colleagues predicts that males’ age and rank influence the occurrence of infanticide: youngest and highest-ranking immigrant males are more likely to commit infanticide […]

Interspecific Infanticide and Infant-Directed Aggression by Spider Monkeys (Ateles hybridus) in a Fragmented Forest in Colombia

Interspecific aggression amongst nonhuman primates is rarely observed and has been mostly related to scenarios of resource competition. Interspecific infanticide is even rarer, and both the ultimate and proximate socio-ecological factors explaining this behavior are still unclear. We report two cases of interspecific infanticide and five cases of interspecific infant-directed aggression occurring in a well-habituated […]

The Association of Intergroup Encounters, Dominance Status, and Fecal Androgen and Glucocorticoid Profiles in Wild Male White-Faced Capuchins (Cebus capucinus)

Androgens play a role in male reproductive competition, frequently via aggression, while glucocorticoids are associated with the stress response. However, the relationships of these hormones with different sources of competition (intra- vs. intergroup) and dominance status are highly variable. Here, we consider the fecal androgen (fA) and glucocorticoid (fGC) profiles of alpha and subordinate male […]

Why leopards commit infanticide

Infanticide is a widespread but seldom observed behaviour that has been shown to convey strong selection forces on some social mammals. However, infanticide in nonsocial species is less clearly understood, particularly the evolutionary function of infanticide. Here we present direct and indirect evidence of infanticide in a large, solitary felid, the African leopard, Panthera pardus, […]

Variable postpartum responsiveness among humans and other primates with “cooperative breeding”: A comparative and evolutionary perspective

This article is part of a Special Issue “Parental Care”.Until recently, evolutionists reconstructing mother–infant bonding among human ancestors relied on nonhuman primate models characterized by exclusively maternal care, overlooking the highly variable responsiveness exhibited by mothers in species with obligate reliance on allomaternal care and provisioning. It is now increasingly recognized that apes as large-brained, […]