Play fighting is common in juvenile mammals as a peri-pubertal form of agonistic behavior preceding adult aggressive behavior. In golden hamsters, play fighting peaks in early puberty around postnatal day 35 (P-35), and gradually matures into adult aggression in late puberty. Though extensively studied, the neural mechanisms underlying play fighting remains poorly understood. My dissertation fo...

Accurate assessment of competitive ability is a critical component of contest behavior in animals, and it could be just as important in human competition, particularly in human ancestral populations. Here, we tested the role that facial perception plays in this assessment by investigating the association between both perceived aggressiveness and perceived fighting ability in fighters' faces and...

Then aims of the current study were 1) to provide cross-national estimates of the prevalence of physical fighting and weapon carrying among adolescents aged 11-15 years; (2) To examine the possible effects of physical fighting and weapon carrying on the occurrence of physical (medically treated injuries) and emotional health outcomes (multiple health complaints) among adolescents within the the...

Single unit activity was recorded extracellularly from the midbrain of rats during fighting behavior and during non-fighting control manipulations. Fighting behavior was elicited by footshock or startle stimuli or occurred spontaneously as a result of prior footshock presentations. Seven cells were found in the midbrain reticular formation and central gray which displayed maximum firing rates d...

As the use of pharmaceuticals and personal care products (PPCPs) continues to rise, these compounds enter the environment in increasing frequency. One such PPCP, fluoxetine, has been found in detectable amounts in aquatic ecosystems worldwide, where it may interfere with the behavior of exposed organisms. Fluoxetine exposure has been found to influence boldness and exploration in a range of fis...

Several studies have found behavioural differences between the interactions of opponents, early in a conflict. These differences consistently predict which individual will be the winner. Surprisingly, opponents appear not to use this information: they continue fighting and even proceed to highly damaging escalation. We attempted to resolve this paradox in a series of experiments on interactions...