The size of copepod prey strongly influenced dietary selectivity by Euchaeta elongata. Adult females (4.2-mm prosome length) showed highest predation rates on adult copepod prey 6501,000 pm long and on intermediate sized copepodid stages of Calanus pacz$cu+s. Selective feeding curves of copepodid stages IV and V of E. elongata showed a slight shift toward smaller prey. The prosome length of the...

BACKGROUND Little is known about the impact of prey sexual dimorphism on predator-prey dynamics and the impact of sex-selective harvesting and trophy hunting on long-term stability of exploited populations. METHODOLOGY AND PRINCIPAL FINDINGS We review the quantitative evidence for sex-selective predation and study its long-term consequences using several simple predator-prey models. These mod...

Non-krill prey remains were recovered from ornithogenic sediments at three active Adélie penguin colonies on Ross Island, to assess long-term dietary trends in this species. Radiocarbon dates place the age of these deposits from a maximum of 947 years ago to the present. We identified 12 taxa of fish and two of squid with the Antarctic silverfish (Pleuragramma antarcticum) as the most abundant ...

This paper describes the GA model using a new selection method inspired by predator-prey interactions. In this model, prey, which represents the decision space vector, will be placed on the vertices of a two-dimensional lattice. Predator, which deals with objective functions, will also be placed on the same lattice randomly. Basic algorithm proposed by Professor Hans-Paul Schwefel and reported ...

One of the most difficult interactions to observe in nature is the relationship between a predator and its prey. When direct observations are impossible, we rely on morphological classification of prey remains, although this is particularly challenging among generalist predators whose faeces contain mixed and degraded prey fragments. In this investigation, we used a polymerase chain reaction an...

The "geographic mosaic" approach to understanding coevolution is predicated on the existence of variable selection across the landscape of an interaction between species. A range of ecological factors, from differences in resource availability to differences in community composition, can generate such a mosaic of selection among populations, and thereby differences in the strength of coevolutio...

through genetic constraints that limit the diversity of classes produced or recruited through evolution is not yet clear. At the same time, rapid evolutionary diversification and variability is the hallmark of venom evolution. Marine cone snails (Conus) are predatory mollusks that fire a venomous harpoon that almost instantly immobilizes target prey (Figure 3). These darts carry an astonishingl...

Current models suggest that (i) filamentous bacteria are protected against predation by nanoflagellates, (ii) prey size is positively correlated with prey-predator contact probability, and (iii) contact probability is mainly responsible for size-selective predation by interception-feeding flagellates. We used five strains of filamentous bacteria and one bacterivorous nanoflagellate, Ochromonas ...

Heterotrophic nanoflagellates play an important role in marine microbial processes as the principal consumers of, and a control point for, heterotrophic and photosynthetic bacterial production. Nanoflagellates are generally smooth spherical cells that capture picoplankton prey by chance contact with their cell surface as they swim randomly through the fluid medium. This mode of feeding is relat...

—During a 17-yr telemetry study, we examined the diet and ambush behavior of a population of Crotalus horridus in southeastern Virginia. Forty dietary items were identified from 37 fecal samples. We documented 722 instances of snakes in an ambush posture, 61% of which were in a vertical-tree posture, as if hunting arboreal prey at the base of a tree. The most common prey items were Eastern Gray...