Multiple predator effects (MPEs) can modify the strength of pest regulation, causing positive or negative deviations from those that are predicted from independent effects of isolated predators. Despite increasing evidence that omnivory can shape predator-prey interactions, few studies have examined the impact of alternative plant food on interactions between multiple predators. In the present ...

Three experiments modeled after infant studies were run on four great ape species (Gorilla gorilla, Pongo pygmaeus, Pan troglodytes, Pan paniscus) to investigate their reasoning about solidity and gravity constraints. The aims were: (a) to find out if great apes are subject to gravity biased search or display sensitivity for object solidity, (b) to check for species differences, and (c) to asse...

Trypanosoma spp. of ground squirrels and most other rodents belong to the 3ubgenus Herpetosoma and have been recorded from approximately 80 to 90 different species of rodents throughout the world (Davis, 1952). They are often designated as leurisi-like after the type species, Trypanosoma (Herpetosoma) lewisi (Kent) Laveran & Mesnil. All are very similar in appearance and cannot be differentiate...

Omnivorous arthropods make dietary choices according to the environment in which they forage, mainly availability/quality of plant and/or prey resources. Such decisions and their subsequent impacts on life-history traits may be affected by the availability of nutrients and water to plants, that is, through bottom-up forces. By setting up arenas for feeding behavior observation as well as glassh...

Females increase their risk of mating with heterospecifics when they prefer the traits of conspecifics that overlap with traits found in heterospecifics. Xiphophorus pygmaeus females have a strong preference for larger males, which could lead to females preferring to mate with heterospecific males; almost all sympatric X. cortezi males are larger than X. pygmaeus males. In this study, we show t...

Age, growth and maturation of the temperate ‘mini-maximalist’ Idiosepius notoides from Tasmania is described and compared with those of its tropical congener Idiosepius pygmaeus. Using statolith increment analysis, growth of I. notoides was best described by a power curve with a maximum age of 115 days recorded. Males have a shorter lifespan than females, however growth rates were similar betwe...