While foraging theory predicts that predatory responses should be determined by the energy content and size of prey, it is becoming increasingly clear that carnivores regulate their intake of specific nutrients. We tested the hypothesis that prey nutrient composition and predator nutritional history affects foraging intensity, consumption, and prey selection by the wolf spider, Pardosa milvina....

1. Optimal foraging theory assumes that a predator preys selectively to maximize fitness gain. The associated model assesses predator’s fitness gain by estimating prey profitability in terms of appropriate foraging costs and benefits. While model developing, unsuccessful foraging was included in the model because it is inevitable and costly for a predator. However, it has rarely been taken into...

A spider orb web is an extended phenotype; it modifies and interacts with the environment, influencing spider physiology. Orb webs are plastic, responding to variations in prey parameters. Studies attempting to understand how nutrients influence spider orb-web plasticity have been hampered by the inability to decouple prey nutrients from other, highly correlated, prey factors and the intrinsic ...

The presence of predators alters the evolutionary pressures acting on prey populations, often driving them to engage in new behaviors in order to avoid being the target of an attack. One common antipredator behavior is group formation, which can reduce the odds of any individual prey being the target of a given attack, typically scaling inversely with the number of prey in the group. This “dilu...

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...

All mammals thus far studied sleep, yet important questions remain concerning the ecological factors that influence sleep patterns. Here, we developed an evolutionary individualbased model to investigate the effect of predation pressure on prey sleep. We investigated three ecological conditions, including one that assumed a dynamic interaction between predator and prey behaviour. In condition 1...

All mammals thus far studied sleep, yet important questions remain concerning the ecological factors that influence sleep patterns. Here, we developed an evolutionary individualbased model to investigate the effect of predation pressure on prey sleep. We investigated three ecological conditions, including one that assumed a dynamic interaction between predator and prey behaviour. In condition 1...

Environment-friendly farming techniques seek to increase invertebrate biodiversity in part with the intention of encouraging greater numbers of predators that will help to control crop pests. However, in theory, this effect may be negated if the availability of a greater abundance and diversity of alternative prey diverts predators away from feeding on pests. The hypothesis that access to alter...

The evolution of aposematism, a phenomenon where prey species conspicuously advertise their unprofitability to predators, is puzzling. How did conspicuousness evolve, if it simultaneously increased the likelihood of an inexperienced predator to detect the prey and presumably kill it? Antiapostatic selection, where rare prey is predated relatively more often, is considered as another major diffi...

Understanding how prey capture rates are influenced by feeding ecology and environmental conditions is fundamental to assessing anthropogenic impacts on marine higher predators. We compared how prey capture rates varied in relation to prey size, prey patch distribution and prey density for two species of alcid, common guillemot (Uria aalge) and razorbill (Alca torda) during the chick-rearing pe...