Dominance, aggression, and glucocorticoid levels in social carnivores

In social animals, reproductive success is often related to social dominance. In cooperatively breeding birds and mammals, reproductive rates are usually lower for social subordinates than for dominants, and it is common for reproduction in subordinates to be completely suppressed. Early research with captive animals showed that losing fights can increase glucocorticoid (GC) secretion, a […]

Function of Notification in Papio hamadryas

Notification is a form of ritualized greeting behavior performed by adult male hamadryas baboons (Papio hamadryas). Originally observed in the wild when harem leaders signaled the direction of travel to their followers on daily foraging marches, its true function is unknown. Notification involves the approach of an adult male baboon to another male, the presentation […]

The Effects of Social Experience on Aggressive Behavior in the Green Anole Lizard (Anolis carolinensis)

To understand how context-specific aggression emerges from past experience, we examined how consecutive aggressive encounters influence aggressive behavior and stress responses of male green anole lizards (Anolis carolinensis). Animals were shown a video clip featuring an aggressively displaying conspecific male, which provoked aggressive responding, while control animals viewed a neutral video. After 5 d of […]

Agonistic Behavior in Freshwater Crayfish The Influence of Intrinsic and Extrinsic Factors on Aggressive Encounters and Dominance

Fighting success and dominance in crayfish depends on a variety of extrinsic and intrinsic factors. Most intrinsic factors studied to date are related to the physical size of the crayfish. Larger crayfish or those with larger chelae often have advantages in agonistic interactions. Age, sex, and reproductive status can influence the physical size of the […]

Social spacing of crayfish in natural habitats: what role does dominance play?

We examined the impact of dominance on crayfish social spacing and resource control. Spatial distributions of individual crayfish, Orconectes propinquus, were recorded from five sample sites in Douglas Lake, MI, USA. Crayfish populations from each site were collected and then immediately transferred to artificial ponds in order to reproduce potential dominance hierarchies. After 15 h […]

Male mating patterns in wild multimale mountain gorilla groups

Although mountain gorillas,Gorilla gorilla beringei, are classified as having a one-male mating system, approximately 40% of the social units are multimale groups. I observed two multimale groups of mountain gorillas at the Karisoke Research Center, Rwanda, Africa, for 17 months to determine male mating patterns and male–male mating harassment in relation to both male dominance […]

Influence of dominance status on adrenal activity and ovarian cyclicity status in captive African elephants

Abstract 10.1002/zoo.20292.abs The North American African (Loxodonta africana) elephant population is not self-sustaining, in part because of a high rate of abnormal ovarian activity. About 12% of adult females exhibit irregular cycles and 31% do not cycle at all. Our earlier work revealed a relationship between dominance status and ovarian acyclicity, with dominant females being […]

GPS assessment of the use of exhibit space and resources by African elephants (Loxodonta africana)

Abstract 10.1002/zoo.20250.abs In public discussions of animal rights and welfare, we as members and proponents of zoological institutions often face significant challenges addressing the concerns of our detractors due to an unfortunate deficiency in systematically collected and published data on the animals in our collections. In the case of elephants, there has been a paucity […]

Social and spatial relationships in captive southern white rhinoceros (Ceratotherium simum simum)

Abstract 10.1002/zoo.20143.abs Although critical to the conservation of white rhinoceros, captive breeding has proven challenging because of the poor and irregular reproductive health of many captive rhinos, and social interactions may play a significant role. This research investigated the social and spatial relationships of two captive groups of southern white rhinoceros (Ceratotherium simum simum) by […]

Personality and foraging decisions in fallow deer, Dama dama

Recent studies have examined the ecological and evolutionary bases for variation in animal personality. However, only a few such studies have examined how foraging parameters are influenced by different personality domains. In wild ungulates, the trade-off between the time spent on food intake and antipredator behaviour differs between individuals, but the underlying reason for this […]