The seed predator Argyresthia conjugella Zeller has rowan as its preferred host plant; in years of poor fruiting rowan, it oviposits on apples. To improve the knowledge this apple pest, rowanberries were collected from localities all over Norway 1971 to 1985, and predators their parasitoids allowed emerge for up five years. Two species predators, A. Megastimus brevicaudis Ratzeburg, seven paras...

We examine optimal patch allocation strategies in a population structured by size or some other characteristic. By treating size-specific differences among patches as limiting factors, we create a single framework to analyse foraging for two resources, foraging in the presence of predators and foraging in the presence of competition. The ideal free distribution or size segregation are optimal o...

Fear is one of the most universal human emotions and many common fears, such as aversions toward predatory animals, has been observed cross-culturally. Previous research has indicated that humans have an evolved predator detection mechanism (Mineka & Ohman, 2002). The present research explored this innate predator detection mechanism in infants by testing whether they are able to learn associat...

Invasive species threaten biodiversity globally, and invasive mammalian predators are particularly damaging, having contributed to considerable species decline and extinction. We provide a global metaanalysis of these impacts and reveal their full extent. Invasive predators are implicated in 87 bird, 45 mammal, and 10 reptile species extinctions-58% of these groups' contemporary extinctions wor...

A recent review of published studies revealed that predators generally have lower population densities than non-predators in a variety of communities. We report here similar results for a highly replicated study of macroinvertebrates that colonized very uniform detrital microcosms in an old field. This pattern persisted even though predators usually were smaller than non-predators, as determine...

repeatability, (the consistency with which a given trait is expressed) of aggressiveness against prey (attack latency) in gravid females of the predatory mite neoseiulus californicus (mcgregor) was examined. in two experiments, prey - conspecific individuals, the onion thrips thrips tabaci (lindeman), and the two-spotted spider mite tetranychus urticae koch- were repeatedly offered in various n...

That predators attack and prey defend is an oversimplified view. When size changes during development, large prey may be invulnerable to predators, and small juvenile predators vulnerable to attack by prey. This in turn may trigger a defensive response in adult predators to protect their offspring. Indeed, when sizes overlap, one may wonder "who is the predator and who is the prey"! Experiments...

abstract the laelapidae is a large family with worldwide distribution. many laelapids are ectoparasitic on small mammals or associated with arthropods, although some species are free living and predators especially in soil habitat; also they are common in stored products. during three years (2007-2009) of faunestic survey, samples were collected from different habitats such as soil, plant litte...

Calls of avian predators potentially predict danger for murine rodents. Indeed, exposure of field-experienced rodents to owl calls induces defensive behavior suggesting that recognition of vocalizations of avian predators is innate. To address this hypothesis, we investigated whether laboratory-reared and predator-naive rodents (mice, gerbils, rats) express defensive behavior in response to cal...