User:Walter Moczygemba/sandbox

Pursuit Predation is a form of predation marked by a chase from predators seeking prey. The chase can be initiated either by predators or by prey, alerted by a predators presence, that attempt to flee before predators give chase. The chase ends with either the predator's capture and consumption of the prey, effectively diminishing the prey's fitness, or with the prey escaping the predators hunt, thus maintaining the prey's fitness, but leaving both prey and predator at metabolic losses. Pursuit is typically observed in carnivorous organisms, with animals being the most transparent examples of pursuit predators.

Strategy

In depth analysis of predation: beginning, during, and afterwards, important to make distinctions from not only ambush, but other types if necessary. There is still uncertainty as whether predators behave with a general tactic or strategy while preying. Certain predators will scout potential prey, assessing prey quantity, prey density, and, if a member of predator group, the spread of other conspecfics( ). During a chase, predators may either exhaust their energy rapidly or pace themselves when anticipating a long pursuit.

Evolutionary Basis of the Behavior

Evolution as a countermeasure

Current theory on the evolution of pursuit predation suggests that the behavior is actually an evolutionary countermeasure to prey adaptation. Prey animals vary in their likelihood to avoid predation, and it is predation failure that drives evolution of both prey and predator . Predation failure rates vary wildly across the animal kingdom; raptorial birds can fail anywhere from 20% to 80% of the time in predation, while predatory mammals usually fail more than half the time . Prey adaptation drives these low rates in three phases: the detection phase, the pursuit phase, and the resistance phase . The pursuit phase drove the evolution of distinct behaviors for pursuit predation. As selective pressure on prey is higher than on predators adaptation usually occurs in prey long before the reciprocal adaptations in predators. Evidence in the fossil record supports this, with no evidence of modern pursuit predators until the late Tertiary . Certain adaptations, like long limbs in ungulates, that were thought to be adaptive for speed against predatory behavior have been found to predate predatory animals by over 20 million years. Because of this, modern pursuit predation is an adaptation that may have evolved separately and much later as a need for more energy in colder and more arid climates. Longer limbs in predators, the key morphological adaptation required for lengthy pursuit of prey, is tied in the fossil record to the late Tertiary. It is now believed that modern pursuit predators like the wolf and lion evolved this behavior around this time period as a response to ungulates increasing feeding range . As ungulate prey moved into a wider feeding range to discover food in response to changing climate, predators evolved the longer limbs and behavior necessary to pursue prey across larger ranges. In this respect, pursuit predation is not co-evolutionary with prey adaptation, but a direct response to prey. Prey adaptation to climate is the key formative reason for evolving the behavior and morphological necessities of pursuit predation.

Evolution from an Ecological Basis

Pursuit predation revolves around a distinct movement interaction between predator and prey; as prey move to find new foraging areas, predators should move with them. Predators congregate in areas of high prey density , and prey should then avoid these areas in turn . Because of these interactions, Spatial patterns of predators and prey are important in preserving population size. Prey attempts to avoid predation and find food are coupled with predator attempts to find food and compete with other predators. These interactions act to preserve populations . Models of spatial patterns and synchrony of predator-prey relationships can be used as support for the evolution of pursuit predation as one mechanism to preserve these population mechanics. By pursuing prey over long distances, predators actually improve longterm survival of both their own population and prey population through population synchrony. Pursuit predation acts to even out population fluctuations by moving predatory animals from areas of high predator density to low predator density, and low prey density to high prey density. This keeps migratory populations in synchrony, which increases metapopulation persistence . Pursuit predation’s effect on population persistence is more marked over larger travel ranges. Predator and prey levels are usually more synchronous in predation over larger ranges, as population densities have more ability to even out . Pursuit predation can then be supported as an adaptive mechanism for not just individual feeding success but also metapopulation persistence.

Invertebrates

Dragonflies are skilled aerial pursuer; they have a 97% success prey capture rate. This success rate is a consequence of the "decision-making" of which prey to pursue based on initial conditions. Observations of several species of perching dragonflies show more pursuit initiations at larger starting distances for larger size prey species than for much smaller prey. Further evidence points to a potential foraging strategy of dragonflies choosing to pursue larger prey at any given opportunity, due to more substantial metabolic rewards. This is in spite of the fact that larger prey typically stipulate faster prey and less successful pursuits. Dragonflies high success prey capture rate may also be due to their "interception" foraging method, unlike the tracking foraging methods, in which predators focus on closing in on the current position of their prey. Instead the interception method has the dragonfly seeking the position directly ahead of their prey as a way of surmising a prey's future location. Perching dragonflies (the Libellulidae family), the largest family of dragonflies, have been observed "staking out" high density prey spots prior to pursuit. There are no noticeable distinctions in prey capture efficiency between male and female dragonflies. Further, percher dragonflies are are more likely to engage in pursuit when prey come within a subtend angle of around 1-2 degrees. Angles greater than this are outside of a dragonflies visual range.