Schedule-Induced Aggression in Humans and Animals: A Comparative Parametric Review

Studies of animal and human aggression induced by schedules of reinforcement are reviewed. Parameters reviewed include: schedules, characteristics of induced aggression, subject variables, target variables, and the control or modification of schedule-induced aggression. With the exception of temporal locus of schedule-induced attack, the parameters identified with animal subjects are remarkably similar to those identified with […]

Who is happy?

A flood of new studies explores people’s subjective well-being (SWB). Frequent positive affect, infrequent negative affect, and a global sense of satisfaction with life define high SWB. These studies reveal that happiness and life satisfaction are similarly available to the young and the old, women and men, blacks and whites, the rich and the working-class. […]

Fluctuating asymmetry as an animal welfare indicator — A review of methodology and validity

It has been suggested that fluctuating asymmetry (FA) reflects an animal’s ability to cope with the sum of challenges during its growing period and, thus, is a potential welfare indicator. In this review we investigate the evidence of associations between FA and other welfare indicators measured at the level of the individual and of effects […]

Spontaneous discrimination of natural stimuli by chimpanzees (Pan troglodytes)

Six chimpanzees ( Pan troglodytes) were presented with pairs of color photographic images of 5 different categories of animals (cat, chimp, gorilla, tiger, fish). The subjects responded to each pair using symbols for “same” and “different.” Both within- and between-category discriminations were tested, and all chimpanzees classified the image pairs in accordance with the 5 […]

Zoo Animals and Their Human Audiences: What is the Visitor Effect?

The presence of human visitors has been shown to affect the behaviour of several different mammalian species in a number of different zoos, but the behavioural changes observed are not always consistent with a simple ‘stressful influence’ explanation. Data for non-primate species are too sparse to draw meaningful conclusions; but for primates, the evidence reviewed […]

Dogs (Canis familiaris) learn from their owners via observation in a manipulation task

Eighty-seven pet dogs (Canis familiaris) were involved in an experiment in which they had to solve a task to obtain a ball. After witnessing a full demonstration by their owner (10 times pushing the handle of the box, which released a ball), most dogs preferred to touch the handle sooner and more frequently in comparison […]

Sex-Specific Differences in Olfactory Sensitivity for Putative Human Pheromones in Nonhuman Primates

In humans, the volatile C19-steroids androsta-4,16-dien-3-one (AND) and estra-1,3,5(10),16-tetraen-3-ol (EST) have been shown to modulate autonomic nervous system responses, and to cause hypothalamic activation in a gender-specific manner. Using two conditioning paradigms, the authors here show that pigtail macaques and squirrel monkeys of both sexes were able to detect AND and EST at concentrations in […]

Referential Understanding of Videos in Chimpanzees (Pan troglodytes), Orangutans (Pongo pygmaeus), and Children (Homo sapiens)

Performance on identical search tasks based on cues directly perceived or indirectly perceived through video were compared among a group of 4 adult chimpanzees (Pan troglodytes), a group of 2 adult orangutans (Pongo pygmaeus), and a group of 36 children (between 2 and 3 years of age). Children comprehended directly perceived cues but had difficulty […]

Obey or Not Obey? Dogs (Canis familiaris) Behave Differently in Response to Attentional States of Their Owners

Sixteen domestic dogs (Canis familiaris) were tested in a familiar context in a series of 1-min trials on how well they obeyed after being told by their owner to lie down. Food was used in 1/3 of all trials, and during the trial the owner engaged in 1 of 5 activities. The dogs behaved differently […]

Depressive behavior in young monkeys subjected to vertical chamber confinement

Young rhesus monkeys were confined in vertical chambers for 6 wk., and their subsequent behavior over a 9-mo. period in both a home-cage and playroom situation was compared with that of like-aged monkeys housed individually or in pairs. In comparison to both control groups, chambered monkeys exhibited excessive amounts of self-clasp and huddle, abnormally low […]