In the present paper we study a tri-trophic Lotka-Volterra food web model with omnivory and predator switching. We observe that if the intensity of predator switching increases the chaotic behavior of the omnivory model will be reduced. We conclude that the predator switching mechanism enhances the stability of an otherwise chaotic system.

1. Theory suggests that the relationship between predator diversity and prey suppression should depend on variation in predator traits such as body size, which strongly influences the type and strength of species interactions. Prey species often face a range of different sized predators, and the composition of body sizes of predators can vary between communities and within communities across se...

a r t i c l e i n f o The ecological effects of predator removal and its consequence on prey behavior have been investigated widely; however, predator removal can also cause contemporary evolution of prey resulting in prey genetic change. Here we tested the role of predator removal on the contemporary evolution of prey traits such as movement, reproduction and foraging. We use EcoSim simulation...

BACKGROUND The role of glucocorticoids in extinction of traumatic memories has not been fully characterized despite its potential as a therapeutic target for acquired posttraumatic stress disorder (PTSD). The predator stress paradigm allows us to determine whether glucocorticoids mediate the extinction of both context-dependent and context-independent fear memories. METHODS Male C57BL/6J mice...

Understanding the factors responsible for generating size variation in cohorts of organisms is important for predicting their population and evolutionary dynamics. We group these factors into two broad classes: those due to scaling relationships between growth and size (size-dependent factors), and those due to individual trait differences other than size (size-independent factors; e.g., morpho...

In evolutionary biology, predator-prey species pairs can be observed participating in evolutionary arms races between adaptations and counter-adaptations. For example, as a prey becomes more adept at avoiding capture, its predator becomes a more adept hunter. The rough-skinned newt (Taricha granulosa) produces a toxin that protects it from virtually all predators, except one. That one predator ...

In this study, we aimed to evaluate the effects of a short pulse exposure of the pyrethroid lambda-cyhalothrin (LC) on the predator and anti-predator behaviour of the same species; Gammarus pulex. Predator behaviour, at the level of the individual, was studied in indoor microcosms using video tracking equipment during simultaneous exposure of the predator (G. pulex) and its prey (Leuctra nigra)...

Body size governs predator-prey interactions, which in turn structure populations, communities, and food webs. Understanding predator-prey size relationships is valuable from a theoretical perspective, in basic research, and for management applications. However, predator-prey size data are limited and costly to acquire. We quantified predator-prey total length and mass relationships for several...