From a plant's perspective, the difference between a seed predator and a seed disperser should be straightforward: attract animals that will disperse seeds and defend seeds from potential predators. Unlike pulp-eating frugivores, seed predators regularly encounter diverse plant protective mechanisms. The purpose of this paper is to examine feeding constraints, morphological adaptations, and the...

Alien predators are widely considered to be more harmful to prey populations than native predators. To evaluate this expectation, we conducted a meta-analysis of the responses of vertebrate prey in 45 replicated and 35 unreplicated field experiments in which the population densities of mammalian and avian predators had been manipulated. Our results showed that predator origin (native versus ali...

this paper reviews the research on taxonomy of the trombidioidea in iran, with an updated checklist of 32 species (+5 undetermined species) belonging to five families and 22 genera. among them, 27 species (+1 undetermined species) are reported based on larvae only, three undetermined species based on adults only, and six species based on both larval and post-larval stages. also, 14 species (+3 ...

BACKGROUND In marine pelagic ecosystems, the spatial distribution of biomass is heterogeneous and dynamic. At large scales, physical processes are the main driving forces of biomass distribution. At fine scales, both biotic and abiotic parameters are likely to be key determinants in the horizontal and vertical distribution of biomass, with direct consequences on the foraging behaviour of diving...

We investigate the Volterra ecosystem driven by correlated noises. The competition of the predators induces an increasing in population density of the predators. The competition of the preys, however, leads the predators to decay. The predators may have better stability under strong correlated noises. The predators undergo a sensitivity to a random environment, whereas the preys exhibit a surpr...

in this paper, we introduce fractional order of a planar fractional prey-predator system with a nonmonotonic functional response and anti-predator behaviour such that the adult preys can attack vulnerable predators. we analyze the existence and stability of all possibleequilibria. numerical simulations reveal that anti-predator behaviour notonly makes the coexistence of the prey and predator po...

Apart from being notorious outbreak pests, locusts are of interest because of their expression of density-dependent "phase polyphenism." In this remarkable form of phenotypic plasticity, changes in local population density generate distinct solitarious and gregarious phases that differ in behavior, physiology, and appearance. A hallmark of phase polyphenism in outbreak species is the transition...

Predators play a key role in shaping natural ecosystems, and understanding the factors that influence a predator's kill rate is central to predicting predator-prey dynamics. While prey density has a well-established effect on predation, it is increasingly apparent that predator density also can critically influence predator kill rates. The effects of both prey and predator density on the functi...