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Predation is a biological interaction in which one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill the host ) and parasitoidism (which always does, eventually).
Examples include many moth, butterfly, and fish species that have "eye-spots". These are large dark markings that help prey escape by causing predators to attack a false target. For example, the gray hairstreak (Strymon melinus) shows the false head at its rear; it has a better chance of surviving an attack to that part than an attack to the head.
On the other hand, the common definition of adaptation is a central concept in evolution: a trait that was functional to the reproductive success of the organism and that is thus now present due to being selected for; that is, function and evolution are inseparable.
Experiments on blue jays suggest they form a search image for certain prey.. Visual predators may form what is termed a search image of certain prey.. Predators need not locate their host directly: Kestrels, for instance, are able to detect the faeces and urine of their prey (which reflect ultraviolet), allowing them to identify areas where there are large numbers of voles, for example.
Shimmering behaviour of Apis dorsata (giant honeybees). A group of animals fleeing from a predator shows the nature of herd behavior, for example in 1971, in the oft-cited article "Geometry for the Selfish Herd", evolutionary biologist W. D. Hamilton asserted that each individual group member reduces the danger to itself by moving as close as possible to the center of the fleeing group.
The definition of preference will therefore impact the understanding of switching. The most common definition of preference is the relationship between the ratio of prey in the environment and the ratio of prey in a predator's diet. It has been independently proposed a number of times and is described by the equation:
An extensively studied example is the fiddler crab. When exposed to a predator, fiddler crabs move in ways that are consistent with the selfish herd theory. [5] Dispersed groups are more likely to form an aggregate when subjected to danger and crabs attempt to run toward the center of a forming group. [12] Selfish herd behavior is seen also in:
The numerical response in ecology is the change in predator density as a function of change in prey density. The term numerical response was coined by M. E. Solomon in 1949. [ 1 ] It is associated with the functional response , which is the change in predator's rate of prey consumption with change in prey density.