Aggressive behaviour traits predict physiological stress responses in Nile tilapia (Oreochromis niloticus)

This study tested whether aggressive behaviour can predict individual variation in stress responses of Nile tilapia Oreochromis niloticus.We used a mirror test to measure tendency to aggressive behaviour, and calculated the attack frequency and time until the first attack (latency) for each fish. One day later, we measured plasma cortisol and glucose, and two days […]

Social experience in early ontogeny has lasting effects on social skills in cooperatively breeding cichlids

The early social environment can affect the social behaviour of animals throughout life. We tested whether the presence of adults during early development influences the social behaviour of juveniles later on in the cooperatively breeding cichlid Neolamprologus pulcher. In a split-brood design we raised half of the broods together with parents and with or without […]

Differential resource use, growth, and the ontogeny of social relationships in the green iguana

Growth rates, resource use, and ontogeny of behavior patterns were examined in captive groups of juvenile green iguanas (Iguana iguana). Four groups were housed in large arenas where supplemental heat and perch sites were limited, whereas two control groups were housed in similar arenas without limited resources. Growth, frequency and types of displays, behavioral interactions, […]

Companion Dog Temperament Traits

Owners rated their companion dogs (Canis faamiliarus) on the frequency of occurrence of 127 descriptions of behavior. We conducted an exploratory principal components analysis of these behaviors for 2,018 participants that produced 22 interpretable factors (or traits). Four related to aggression indicate that aggression is not a unitary concept. Three factors relate to play and […]

Effect of food abundance on aggressiveness and territory size of juvenile rainbow trout, Oncorhynchus mykiss

How food abundance affects (1) whether or not individuals defend territories and (2) what size of territory is defended are crucial to understanding the role that territoriality plays in regulating the population size of stream-dwelling salmonids. The threshold model of feeding territoriality predicts that territorial defence will be most intense at intermediate levels of food […]

Aggression and sex differences in lateralization in the zebrafish

Aggression plays an important role in survival and reproduction. It can be measured using mirror and dyadic tests, but there is some debate about whether interactions with a mirror image and with a real opponent measure the same aspects of aggressiveness. Variation in aggressiveness among individuals has been linked to behavioural lateralization. Lateralization, the preference […]