Evaluating mood changes in response to anthropogenic noise with a response-slowing task in three species of zoo-housed primates

In the zoo environment, anthropogenic noise is common as sound levels fluctuate due to visitors, construction, habitat design, and special events. In this study, changes in the mood of three species of zoo-housed primates in response to a loud annual event were evaluated with the response-slowing paradigm. In this paradigm, animals experiencing anxiety slow responses […]

Habitat Use and Structural Preferences of Captive Western Lowland Gorillas (Gorilla gorilla gorilla): Effects of Environmental and Social Variables

Exhibit naturalism has become the architectural standard for new zoo exhibits, yet our scientific understanding of how animals interact with naturalistic environments is very limited. Given the expense incurred in building new exhibits, it is essential that more information on animal-environment interactions be obtained and that it be incorporated at the outset into exhibit designs. […]

Infant cradling in a captive mother gorilla

Abstract 10.1002/zoo.20197.abs The purpose of the study presented here was to investigate the handedness and cradling preferences of a mother gorilla (Gorilla gorilla) from the Metro Toronto Zoo. The study also examined preferences for handedness for each member of the captive group. Observational data were collected using scan sampling at 60-sec intervals. Handedness was determined […]

Review of medical literature of great apes in the 1980s

Abstract 10.1002/zoo.1430090206.abs The medical problems of great apes including gorillas (Gorilla gorilla), orangutans (Pongo pymaeus), and chimpanzees (Pan sp.) published during the last decade are reviewed. Anesthetic techniques, diseases or organ systems, neoplasia, infectious diseases, and reproductive problems are reviewed. Gonadal tumors and atherosclerosis in great apes appear frequently in the literature. Diseases with suspected […]

Token transfers among great apes (Gorilla gorilla, Pongo pygmaeus, Pan paniscus, and Pan troglodytes): Species differences, gestural requests, and reciprocal exchange

Great apes appear to be the nonhuman primates most capable of recognizing trading opportunities and engaging in transfers of commodities with conspecifics. Spontaneous exchange of goods between them has not yet been reported. We tested gorillas (Gorilla gorilla), orangutans (Pongo pygmaeus), bonobos (Pan paniscus), and chimpanzees (Pan troglodytes) in a token-exchange task involving two conspecifics […]

Discrete quantity judgments in the great apes (Pan paniscus, Pan troglodytes, Gorilla gorilla, Pongo pygmaeus): The effect of presenting whole sets versus item-by-item

The authors examined quantity-based judgments for up to 10 items for simultaneous and sequential whole sets as well as for sequentially dropped items in chimpanzees (Pan troglodytes), gorillas (Gorilla gorilla), bonobos (Pan paniscus), and orangutans (Pongo pygmaeus). In Experiment 1, subjects had to choose the larger of 2 quantities presented in 2 separate dishes either […]

Gorillas (Gorilla gorilla) and Orangutans (Pongo pygmaeus) Encode Relevant Problem Features in a Tool-Using Task

Two important elements in problem solving are the abilities to encode relevant task features and to combine multiple actions to achieve the goal. The authors investigated these 2 elements in a task in which gorillas (Gorilla gorilla) and orangutans (Pongo pygmaeus) had to use a tool to retrieve an out-of-reach reward. Subjects were able to […]