one of the most important predator-prey interactions is functional response which its type and parameters are affected by different factors including host plant characteristics. in this research, the influence of leaf surface on functional response and prey consumption rate of third instar larvae of the episyrphus balteatus (de geer, 1776) (diptera: syrphidae) to third instar nymphs of aphis go...

We study the qualitative properties of population cycles in a predator-prey system where genetic variability allows contemporary rapid evolution of the prey. Previous numerical studies have found that prey evolution in response to changing predation risk can have major quantitative and qualitative effects on predator-prey cycles, including: (1) large increases in cycle period, (2) changes in ph...

the food chain refers to a natural system by which energy is transmitted from one organism to another. in fact, a food chain consists of producers, consumers and decomposition. presence of complex food web increase the stability of the ecosystem. classical food chain theory arises from lotka-volterra model. in the present paper, the dynamics behavior of three level food chain is studied. a syst...

A simple food chain which consists of nutrient, prey and predator with intratrophic predation of the predator is proposed and analyzed. The dynamics of the model depend on the basic reproductive numbers of the prey and predator. Intratrophic predation can have impact on the system only if the basic reproductive number of the predator is greater than 1. In this case, the system may have multiple...

A predator’s per capita feeding rate on prey, or its functional response, provides a foundation for predator–prey theory. Since 1959, Holling’s prey-dependent Type II functional response, a model that is a function of prey abundance only, has served as the basis for a large literature on predator–prey theory. We present statistical evidence from 19 predator–prey systems that three predator-depe...

Relation between species and their livelihood environment in ecological systems is very complex. For that reason, order to study predator-prey relations, modeling essential biomathematics. The vital components of models are prey species' growth function the absence apredator functional response. In this article, we proposed a model with gregarious prey. existing literature, square-root response...

We study a simple replicator model with non-symmetric and nonlocal interactions. Hierarchical structures with prey-predator relations are self-organized from a homogeneous state, induced by the dynamical instability of nonlinear interactions.

Predator-prey relationships are a central component of community dynamics. Classic approaches have tried to understand and predict these relationships in terms of consumptive interactions between predator and prey species, but characterizing the interaction this way is insufficient to predict the complexity and context dependency inherent in predator-prey relationships. Recent approaches have b...