In ecology, predation describes a biological interaction where a predator organism feeds on another living organism or organisms known as prey. The Red-tailed Hawk ( Buteo jamaicensis) is a medium-sized Bird of prey, one of three species colloquially known in the United States as the " The genus Microtus is a group of Voles found in North America and northern Europe and Asia. Ecology (from Greek grc οἶκος oikos, "house(hold" and grc -λογία -logia) is the scientific study of Biological interactions result from the fact that Organisms in an Ecosystem interact with each other in the natural world no organism is an autonomous entity isolated ^[1] Predators may or may not kill their prey prior to feeding on them, but the act of predation always results in the (ecologically significant) death of the prey^[2]. The other main category of consumption is detritivory, the consumption of dead organic material (detritus). A heterotrophs, or chemoorganotrophy ( Greek heterone = (another and trophe = nutrition is an Organism that requires Detritivores, also known as detritus feeders or saprophages, are Heterotrophs that obtain Nutrients by consuming Detritus (decomposing In Biology, detritus is non-living particulate organic material (as opposed to dissolved organic material It can at times be difficult to separate the two feeding behaviors^[1], for example where parasitic species prey on a host organism and then lay their eggs on it for their offspring to feed on its decaying corpse. The key characteristic of predation however is the predator's direct impact on the prey population. On the other hand, detritivores simply eat what is available and have no direct impact on the 'donor' organism(s).

Contents 1 Classification of predators 1.1 Functional classification 1.1.1 True predation 1.1.2 Grazing 1.1.3 Parasitism 1.1.4 Parasitoidism 1.2 Degree of specialization 1.3 Trophic level 1.4 Predation as competition 2 Ecological role 3 Adaptations and behavior 3.1 General 3.2 Predator 3.3 Anti-predator adaptations 3.3.1 Mobbing behavior 3.3.2 Advertising unprofitability 4 Population dynamics 5 Humans and predation 5.1 In conservation 5.2 Biological pest control 6 See also 7 References 8 External links 9 Further reading

Classification of predators

The unifying theme in all classifications of predation is the predator lowering the fitness of its prey, or put another way, it reduces its prey's chances of survival, reproduction, or both. The Sundews ( Drosera) comprise one of the largest genera of Carnivorous plants with over 170 Species. Fitness (often denoted w in Population genetics models is a central concept in evolutionary theory. Ways of classifying predation surveyed here include grouping by trophic level or diet, by specialization, and by the nature of their interaction with prey. In Ecology, trophic dynamics is the system of trophic levels ( Greek trophē, food which describe the position that an organism occupies

Functional classification

Classification of predators by the extent to which they feed on and interact with their prey is one way ecologists may wish to categorize the different types of predation. Instead of focusing on what they eat, this system classifies predators by the way in which they eat, and the general nature of the interaction between predator and prey species. Two factors are considered here: How close the predator and prey are physically (in the latter two cases the term prey may be replaced with host). In Biology, a host is an organism that harbors a Virus or Parasite, or a mutual or Commensal Symbiont, typically providing nourishment Additionally, whether or not the prey are directly killed by the predator is considered, with the first and last cases involving certain death.

True predation

A true predator is one which kills and eats another organism. The lion ( Panthera leo) is a member of the family Felidae and one of four Big cats in the Genus Panthera. The African Buffalo or Cape Buffalo ( Syncerus caffer) is a large African bovid. Whereas other types of predator all harm their prey in some way, this form results in their instant death. Predators may hunt actively for prey, or sit and wait for prey to approach within striking distance, as in ambush predators. Ambush predators or sit-and-wait predators are carnivorous animals that capture prey by stealth or cunning not by speed or necessarily by strength Some predators kill large prey and dismember or chew it prior to eating it, such as a jaguar, while others may eat their (usually much smaller) prey whole, as does a bottlenose dolphin or any snake. The jaguar (Panthera onca,, or—especially in British English — is a New World Mammal of the Felidae family and one of The Bottlenose Dolphin is one of the most common and well-known Dolphins. A snake is an elongate Reptile of the suborder Serpentes Like all reptiles snakes are covered in scales. In some cases the prey organism may die in the mouth or digestive system of the predator. Digestion is the breaking down of chemicals in the body into a form that can be absorbed Baleen whales, for example, eat millions of microscopic plankton at once, the prey being broken down well after entering the whale. The baleen whales, also called whalebone whales or great whales, form the Mysticeti, one of two suborders of the Cetacea (whales dolphins and Seed predation is another form of true predation, as seeds represent potential organisms. Seed predation includes any process inflicted on a Plant ’s seeds by an animal that results in the inviability of the Seed. A seed (in some plants referred to as a kernel) is a small embryonic Plant enclosed in a covering called the seed coat usually with some stored Predators of this classification need not eat prey entirely, for example some predators cannot digest bones, while others can. Bones are rigid organs that form part of the Endoskeleton of Vertebrates They function to move support and protect the various organs of the body produce Some may merely eat only part of an organism, as in grazing (see below), but still consistently cause its direct death.

Grazing

Grazing organisms may also kill their prey species, but this is seldom the case. Grazing generally describes a type of Predation in which an Herbivore feeds on Plants (such as Grasses, or more broadly on a multicellular While some herbivores like zooplankton live on unicellular phytoplankton and have no choice but to kill their prey, many only eat a small part of the plant. Zooplankton are the Heterotrophic (sometimes detritivorous) type of Plankton. Grazing livestock may pull some grass out at the roots, but most is simply grazed upon, allowing the plant to regrow once again. Kelp is frequently grazed in subtidal kelp forests, but regrows at the base of the blade continuously to cope with browsing pressure. Kelp are large Seaweeds ( Algae) belonging to the Brown algae and classified in the order Laminariales Animals may also be 'grazed' upon; female mosquitos land on hosts briefly to gain sufficient proteins for the development of their offspring. Mosquitoes are insects in the family Culicidae. They have a pair of scaled wings a pair of Halteres, a slender body and long legs Proteins are large Organic compounds made of Amino acids arranged in a linear chain and joined together by Peptide bonds between the Carboxyl Starfish may be grazed on, being capable of regenerating lost arms. Starfish (also called sea stars) are any Echinoderms belonging to the class Asteroidea.

Parasitism

Parasites can at times be difficult to distinguish from grazers. Parasitism is a type of symbiotic relationship between Organisms of different Species. Their feeding behavior is similar in many ways, however they are noted for their close association with their host species. While a grazing species such as an elephant may travel many kilometers in a single day, grazing on many plants in the process, parasites form very close associations with their hosts, usually having only one or at most a few in their lifetime. Elephants ( family: Elephantidae) are large land Mammals of the order Proboscidea. This close living arrangement may be described by the term symbiosis, 'living together,' but unlike mutualism the association significantly reduces the fitness of the host. This article is about the biological phenomenon for other uses see Symbiosis (disambiguation The term symbiosis (from the Greek Mutualism is a Biological interaction between individuals of two different Species, where both individuals derive a fitness benefit for example increased Fitness (often denoted w in Population genetics models is a central concept in evolutionary theory. Parasitic organisms range from the macroscopic mistletoe, a parasitic plant, to microscopic internal parasites such as cholera. Mistletoe is the common name for a group of hemi-parasitic Plants in the order Santalales that grow attached to and within the A parasitic plant is one that derives some or all of its sustenance from another plant Cholera, sometimes known as Asiatic cholera or epidemic cholera, is an infectious Gastroenteritis caused by the Bacterium Some species however have more loose associations with their hosts. Lepidoptera (butterfly and moth) larvae may feed parasitically on only a single plant, or they may graze on several nearby plants. Lepidoptera is an order of Insect that includes Moths and butterflies. A butterfly is an Insect of the order Lepidoptera. Like all Lepidoptera butterflies are notable for their unusual life cycle with a A moth is an Insect closely related to the Butterfly, both being of the order Lepidoptera. It is therefore wise to treat this classification system as a continuum rather than four isolated forms.

Parasitoidism

Parasitoids are organisms living in or on their host and feeding directly upon it, eventually leading to its death. A parasitoid is an organism that spends a significant portion of its life history attached to or within a single host Organism which it ultimately kills They are much like parasites in their close symbiotic relationship with their host or hosts. Like the previous two classifications parasitoid predators do not kill their hosts instantly. However, unlike parasites, they are very similar to true predators in that the fate of their prey is quite inevitably death. A well known example of a parasitoids are the ichneumon wasps, solitary insects living a free life as an adult, then laying eggs on or in another species such as a caterpillar. Its larva(e) feed on the growing host causing it little harm at first, but soon devouring the internal organs until finally destroying the nervous system resulting in prey death. The nervous system is a Network of specialized cells that communicate information about an animal's surroundings and itself By this stage the young wasp(s) are developed sufficiently to move to the next stage in their life cycle. Though limited mainly to the insect order Hymenoptera, parasitoids make up as much as 10% of all insect species. Hymenoptera is one of the larger orders of Insects comprising the sawflies, Wasps Bees and Ants The name refers to ^[3]

Degree of specialization

Further information: Generalist and specialist species

Among predators there is a large degree of specialization. A generalist species is able to thrive in a wide variety of environmental conditions and can make use of a variety of different resources (for example a Heterotroph Many predators specialize in hunting only one species of prey. Others are more opportunistic and will kill and eat almost anything (examples: humans, leopards, and dogs). Human beings, humans or man (Origin 1590–1600 L homō man OL hemō the earthly one (see Humus The leopard (lɛpɚd Panthera pardus) is an Old World Mammal of the Felidae family and the smallest of the four roaring The dog ( Canis lupus familiaris) is a domesticated Subspecies of the gray wolf, a Mammal of the Canidae family of the order The specialists are usually particularly well suited to capturing their preferred prey. The prey in turn, are often equally suited to escape that predator. This is called an evolutionary arms race and tends to keep the populations of both species in equilibrium. In Evolutionary biology, an evolutionary arms race is an Evolutionary struggle between competing sets of co-evolving Genes that develop adaptations Some predators specialize in certain classes of prey, not just single species. Almost all will switch to other prey (with varying degrees of success) when the preferred target is extremely scarce, and they may also resort to scavenging or a herbivorous diet if possible. Scavenging, or necrophagy, is a Carnivorous Feeding behaviour in which a predator consumes Corpses or Carrion that were killed ^[4]

Trophic level

Predators are often another organism's prey, and likewise prey are often predators. Though blue jays prey on insects, they may in turn be prey for snakes, which may themselves be the prey of hawks. The Blue Jay ( Cyanocitta cristata) is a Passerine bird and a member of the family Corvidae native to North America. Insects ( Class Insecta) are a major group of Arthropods and the most diverse group of Animals on the Earth with over a million described A snake is an elongate Reptile of the suborder Serpentes Like all reptiles snakes are covered in scales. The term hawk can be used in several ways In strict usage in Europe and Asia, to mean any of the Species in the Subfamily One way of classifying predators is by trophic level. In Ecology, trophic dynamics is the system of trophic levels ( Greek trophē, food which describe the position that an organism occupies Organisms which feed on autotrophs, the producers of the trophic pyramid, are known as herbivores or primary consumers; those that feed on heterotrophs such as animals are known as secondary consumers. An autotroph (from the Greek autos = self and trophe = nutrition is an Organism that produces complex Organic compounds from simple An interesting face(or Trophic pyramid) is a graphical representation designed to show the Biomass or productivity at each Trophic level in a given Herbivory is a form of Predation in which an Organism, known as a herbivore, consumes principally Autotrophs ref name=Campbell>Campbell A heterotrophs, or chemoorganotrophy ( Greek heterone = (another and trophe = nutrition is an Organism that requires Secondary consumers are a type of carnivore, but there are also tertiary consumers eating these carnivores, quartary consumers eating them, and so forth. A carnivore (ˈkɑrnɪvɔər meaning 'meat eater' ( Latin carne meaning 'flesh' and vorare meaning 'to devour' is any animal with a diet consisting Because only a fraction of energy is passed on to the next level, this hierarchy of predation must end somewhere, and very seldom goes higher than five or six levels. A predator at the top of any food chain (that is, one that is preyed upon by no organism) is called an apex predator; examples include the orca, tiger, and crocodile and even omnivorous humans. Food chains, also called food networks and/or trophic networks, describe the feeding relationships between species within an Ecosystem. The Orca or Killer Whale ( Orcinus orca) less commonly Blackfish or Seawolf, is the largest species of the Oceanic dolphin family The tiger ( Panthera tigris) is a member of the Felidae family the largest and the most powerful of the four " Big cats quot in the Genus A crocodile is any Species belonging to the family Crocodylidae (sometimes classified instead as the Subfamily Crocodylinae) An apex predator in one environment may not retain this position if introduced to another habitat, such as dogs among crocodilians.

The problem with this system of classification is that many organisms eat from multiple levels of the food chain. A carnivore may eat both secondary and tertiary consumers, and its prey may itself be difficult to classify for similar reasons. Organisms showing both carnivory and herbivory are known as omnivores. Omnivores (from Latin omne all everything vorare to devour are species that eat both Plants and Animals as their primary Even supposedly strict herbivores may supplement their diet with meat. Carnivorous plants would be very difficult to fit into this classification, producing their own food but also digesting anything that they may trap. Carnivorous plants (sometimes called insectivorous plants) are Plants that derive some or most of their Nutrients (but not Energy) from trapping Organisms which eat detritivores would also be difficult to classify by such a scheme. Detritivores, also known as detritus feeders or saprophages, are Heterotrophs that obtain Nutrients by consuming Detritus (decomposing

Predation as competition

An alternative view offered by Richard Dawkins is of predation as a form of competition: the genes of both the predator and prey are competing for the body (or 'survival machine') of the prey organism. Clinton Richard Dawkins, FRS, FRSL (born 26 March 1941 is a British ethologist, evolutionary biologist, and Popular science Competition can be defined as an interaction between Organisms or Species, in which the fitness of one is lowered by the presence of another History See also History of genetics The existence of genes was first suggested by Gregor Mendel (1822-1884 who in the 1860s studied inheritance ^[5] This is best understood in the context of the gene centered view of evolution. The gene-centered view of evolution, gene selection theory or selfish gene theory holds that Natural selection acts through differential survival of competing

Ecological role

Predators may increase the biodiversity of communities by preventing a single species from becoming dominant. Biodiversity is the variation of Life forms within a given Ecosystem, Biome or for the entire Earth. Such predators are known as keystone species, may have a profound influence on the balance of organisms in a particular ecosystem. A keystone species is a Species that has a disproportionate effect on its environment relative to its abundance An ecosystem is a natural unit consisting of all plants animals and micro-organisms( Biotic factors in an area functioning together with all of the non-living physical ( Introduction or removal of this predator, or changes in its population density, can have drastic cascading effects on the equilibrium of many other populations in the ecosystem. For example, grazers of a grassland may prevent a single dominant species from taking over. ^[6]

Adaptations and behavior

The act of predation can be broken down into a maximum of four stages: Detection of prey, attack, capture and finally consumption. ^[7] The relationship between predator and prey is one which is typically beneficial to the predator, and detrimental to the prey species. Sometimes, however, predation has indirect benefits to the prey species,^[8] though the individuals preyed upon themselves do not benefit. ^[9] This means that, at each applicable stage, predator and prey species are in an evolutionary arms race maximize their respective abilities to obtain food or avoid being eaten. In Evolutionary biology, an evolutionary arms race is an Evolutionary struggle between competing sets of co-evolving Genes that develop adaptations This interaction has resulted in a vast array of adaptations in both groups. An adaptation is a characteristic of an Organism that has been favored by Natural selection and

General

One adaptation helping both predators and prey avoid detection is camouflage, a form of crypsis where species have an appearance which helps them blend into the background. Camouflage is a method of cryptic or concealing coloration that allows an otherwise visible Organism In Ecology, crypsis is the ability of an organism to avoid observation Camouflage consists of not only color, but also shape and pattern. The background upon which the organism is seen can be both its environment (e. g. the praying mantis to the right resembling dead leaves) other organisms (e. The Insect order Mantodea or mantises consists of approximately 2000 species worldwide in Temperate and Tropical habitats of g. zebras' stripes blend in with each other in a herd, making it difficult for lions to focus on a single target). Zebras are African Equids best known for their distinctive white and black stripes The lion ( Panthera leo) is a member of the family Felidae and one of four Big cats in the Genus Panthera. The more convincing camouflage is, the more likely it is that the organism will go unseen.

Mimicry is a related phenomenon where an organism has a similar appearance to another species. Biological mimicry occurs when a group of organisms the mimics, have One such example is the drone fly, which looks a lot like a bee, yet is completely harmless as it cannot sting at all. Eristalis tenax is a European Hoverfly, also known as the drone fly (or "dronefly" Bees are flying Insects closely related to Wasps and Ants Bees are a Monophyletic lineage within the superfamily Apoidea Another example of batesian mimicry is the io moth, (Automeris io), which has markings on its wings which resemble an owl's eyes. The io moth ( Automeris io) is a very colorful North American Moth in the Saturniidae family When an insectivorous predator disturbs the moth, it reveals its hind wings, temporarily startling the predator and giving it time to escape. Predators may also use mimicry to lure their prey, however. Female fireflies of the genus Photuris, for example, copy the light signals of other species, thereby attracting male fireflies which are then captured and eaten. FireFly is the second single by Essex Alternative rock band InMe. Photuris is a Genus of fireflies ( Beetles of the family Lampyridae wherein are the Femme fatale fireflies ^[10]

Predator

While successful predation results in a gain of energy, hunting invariably involves energetic costs as well. The South China tiger or South Chinese tiger ( Panthera tigris amoyensis) also known as the Chinese Amoy or Xiamen tiger is a Subspecies of The Blesbok, or Blesbuck, ( Damaliscus dorcas phillpsi) is related to the Bontebok ( Damaliscus dorcas dorcas) and it is purplish Antelope Biological thermodynamics is a phrase that is sometimes used to refer to Bioenergetics, the study of Energy transformation in the Biological sciences Biological When hunger is not an issue, most predators will generally not seek to attack prey since the costs outweigh the benefits. Hunger is a feeling experienced usually followed by a desire to Eat. For instance, a large predatory fish like a shark that is well fed in an aquarium will typically ignore the smaller fish swimming around it (while the prey fish take advantage of the fact that the apex predator is apparently uninterested). Sharks ( Superorder Selachimorpha) are a type of Fish with a full cartilaginous Skeleton and a highly streamlined body An aquarium (plural aquariums or aquaria) is a Vivarium consisting of at least one transparent side in which Water -dwelling Plants Surplus killing represents a deviation from this type of behaviour. Surplus killing is the behavior Predators exhibit when they kill more prey than they can immediately use The treatment of consumption in terms of cost-benefit analysis is known as optimal foraging theory, and has been quite successful in the study of animal behavior. Cost-benefit analysis is a term that refers both to a formal discipline used to help appraise or assess the case for a Project or proposal which itself is Ethology ( from Greek ἦθος ethos, "character" and λόγος logos, "knowledge") is the scientific study of Animal Costs and benefits are generally considered in energy gain per unit time, though other factors are also important, such as essential nutrients that have no caloric value but are necessary for survival and health. An essential nutrient is a Nutrient required for normal body functioning that cannot be synthesized by the body and must be obtained from a dietary source

Size-selective predation involves predators preferring prey of a certain size. Large prey may prove troublesome for a predator, while small prey might prove hard to find and in any case provide less of a reward. This has led to a correlation between the size of predators and their prey. ^[11] Size may also act as a refuge for large prey, for example adult elephants are generally safe from predation by lions, but juveniles are vulnerable. ^[11]

It has been observed that well-fed predator animals in a lax captivity (for instance, pet or farm animals) will usually differentiate between putative prey animals who are familiar co-inhabitants in the same human area from wild ones outside the area. A pet is an Animal kept for companionship and enjoyment or a househeld animal as opposed to Livestock, Laboratory animals Working animals A farm is an area of land including various structures devoted primarily to the practice of producing and managing food ( Produce, Grains, or Livestock This interaction can range from peaceful coexistence to close companionship; motivation to ignore the predatory instinct may result from mutual advantage or fear of reprisal from human masters who have made clear that harming co-inhabitants will not be tolerated. Pet cats and pet mice, for example, may live together in the same human residence without incident as companions. WikipediaManual of Style (spelling, articles should conform to one overall spelling style of English typically the one most linked to the article topic (if it is geographic A mouse (plural mice) is a small Animal that belongs to one Pet cats and pet dogs under human mastership often depend on each other for warmth, companionship, and even protection, particularly in rural areas. The dog ( Canis lupus familiaris) is a domesticated Subspecies of the gray wolf, a Mammal of the Canidae family of the order

Anti-predator adaptations

Main article: Antipredator adaptations

Antipredator adaptations have evolved in prey populations due to the selective pressures of predation over long periods of time. Antipredator adaptations are Adaptations developed over Evolutionary time which assist Prey organisms in their constant struggle against their

Mobbing behavior

Mobbing behavior occurs when a species turns the tables on their predator by cooperatively attacking or harassing it. Mobbing behavior is an antipredator behavior which occurs when individuals of a certain species mob a Predator by cooperatively attacking or Co-operation or co-operative behaviours are terms used to describe Behaviours by Organisms which are beneficial This is most frequently seen in birds, though it is also known to occur in other social animals. Birds ( class Aves) are bipedal endothermic ( Warm-blooded) Vertebrate animals that lay eggs. For example, nesting gull colonies are widely seen to attack intruders, including humans. Gulls (often informally Seagulls) are birds in the family Laridae Costs of mobbing behavior include the risk of engaging with predators, as well as energy expended in the process; mockingbirds can effectively force a cat or dog to seek something less troublesome. Mockingbirds are a group of New World Passerine Birds from the Mimidae family. One mockingbird might fly in front of the cat or dog, enticing it to lunge, while another pecks at the cat or dog from behind. While mobbing has evolved independently in many species, it only tends to be present in those whose young are frequently preyed on, especially birds. Convergent evolution describes the acquisition of the same biological trait in unrelated lineages It may complement cryptic behavior in the offspring themselves, such as camouflage and hiding. In Ecology, crypsis is the ability of an organism to avoid observation Mobbing calls may be made prior to or during engagement in harassment.

Mobbing behavior has functions beyond driving the predator away. Mobbing draws attention to the predator, making stealth attacks impossible. Mobbing also plays a critical role in the identification of predators and inter-generational learning about predator identification. Reintroduction of species is often unsuccessful because the established population lacks this cultural knowledge of how to identify local predators. Scientists are exploring ways to train populations to identify and respond to predators before releasing them into the wild. ^[12]

Mobbing can be an interspecies activity: it is common for birds to respond to mobbing calls of a different species. Many birds will show up at the sight of mobbing and watch and call, but not participate. It should also be noted that some species can be on both ends of a mobbing attack. Crows are frequently mobbed by smaller songbirds as they prey on eggs and young from these birds' nests, but these same crows will cooperate with smaller birds to drive away hawks or larger mammalian predators. On occasion, birds will mob animals that pose no threat.

Black-headed Gulls are one species which aggressively engages intruding predators, such as Carrion Crows. The Black-headed Gull ( Chroicocephalus ridibundus) is a small Gull which breeds in much of Europe and Asia, and also in coastal eastern The Carrion Crow ( Corvus corone) is a member of the Passerine order of Birds and the Crow family which is native to western Europe Experiments on this species by Hans Kruuk involved placing hen eggs at intervals from a nesting colony, and recording the percentage of successful predation events as well as the probability of the crow being subjected to mobbing. ^[13] The results showed decreasing mobbing with increased distance from the nest, which was correlated with increased predation success. Mobbing may function by reducing the predator's ability to locate nests, as predators cannot focus on locating eggs while they are under direct attack.

Advertising unprofitability

Once a predator has detected its prey, one would expect it to pursue it. However, it is not always profitable for the predator to do so. Consider the example of a Thomson's Gazelle being spotted by a predator. The Thomson's gazelle ( Eudorcas thomsoni) is one of the best-known Gazelles It is named after explorer Joseph Thomson, and is often referred to as the " Giving chase to prey requires a sacrifice in energy. If, however, there is some way the prey species can convey the information that it is unprofitable, energy will be saved by both organisms. Thomson's Gazelles are hunted by species such as lions and cheetahs. The lion ( Panthera leo) is a member of the family Felidae and one of four Big cats in the Genus Panthera. The cheetah ( Acinonyx jubatus) is an atypical member of the cat family ( Felidae) that is unique in its speed while lacking climbing abilities When they see the predator approach, they may start to run away, but then slow down and stot. Stotting describes a behavior involving jumping into the air with the legs kept straight and stiff, and the white rear fully visible. Stotting (also pronking or pronging) is a gait of Quadrupeds, particularly Gazelles (e Obviously this behavior is maladaptive if they hope to outrun the predator, so it must serve some other purpose. Although other hypotheses have been put forward, evidence supports the proposition that they stot to signal an unprofitable chase. Scientific hypothesis is a Hypothesis (a testable Conjecture) used as a tentative explanation of an observation but which has not yet been fully tested by the prediction Animal communication is any Behaviour on the part of one Animal that has an effect on the current or future behaviour of another animal For example, cheetahs abandon more hunts when the gazelle stots, and in the event they do give chase, they are far less likely to make a kill. ^[14]

Aposematism, where organisms are brightly colored as a warning to predators, is the antithesis of camouflage. Some organisms pose a threat to their predators - for example they may be poisonous, or able to harm them physically. In the context of Biology, poisons are substances that can cause damage, Illness, or Death to Organisms usually by Aposematic coloring involves bright, easily recognizable and unique colors and patterns. Upon being harmed (e. g. stung) by their prey, the appearance of such an organism will be remembered as something to avoid. In Psychology, memory is an organism's ability to store retain and subsequently retrieve information

Population dynamics

It is fairly clear that predators tend to lower the survival and fecundity of their prey, but on a higher level of organization, populations of predator and prey species also interact. Fecundity, derived from the word fecund, generally refers to the ability to Reproduce. In Biology a population is the collection of inter-breeding organisms of a particular Species; in Sociology It is obvious that predators depend on prey for survival, and this is reflected in predator populations being affected by changes in prey populations. It is not so obvious, however, that predators affect prey populations. Eating a prey organism may simply make room for another if the prey population is approaching its carrying capacity. The supportable Population of an Organism, given the food habitat, water and other necessities available within an environment is known as the environment's

The population dynamics of predator-prey interactions can be modelled using the Lotka–Volterra equations. Population dynamics is the study of marginal and long-term changes in the numbers individual weights and age composition of individuals in one or several Populations and The Lotka–Volterra equations, also known as the predator-prey equations, are a pair of first order Non-linear, Differential equations frequently used These provide a mathematical model for the cycling of predator and prey populations. Note The term model has a different meaning in Model theory, a branch of Mathematical logic.

Humans and predation

In conservation

Predators are an important consideration in matters relating to conservation. "Conservation Biology" redirects here For the Scientific journal, see Conservation Biology (journal. Introduced predators may prove too much for populations which have not coevolved with them, leading to possible extinction. An introduced species (also known as naturalized species or exotic species) is an Organism that is not indigenous to a given location but In a broad sense biological co-evolution is "the change of a biological object triggered by the change of a related object" In Biology and Ecology, extinction is the cessation of existence of a Species or group of taxa. This will depend largely on how well the prey species can adapt to the new species, and whether or not the predator can turn to alternative food sources when prey populations fall to minimal levels. If a predator can use an alternative prey instead, it may shift its diet towards that species in a behavior known as functional response, while still eating the last remaining prey organisms. In Ecology, functional response is a term used to describe the relationship between the density On the other hand the prey species may be able to survive if the predator has no alternative prey - in this case its population will necessarily crash following the decline in prey, allowing some small proportion of prey to survive. Introduction of an alternative prey may well lead to the extinction of prey, as this constraint is removed.

Predators are often the species endangered themselves. Competition for prey from other species could prove the end of a predator - if their ecological niche overlaps completely with that of another the competitive exclusion principle requires only one can survive. Interspecific competition, in Ecology, is a form of competition in which individuals of different Species vie for the same resource in an ecosystem In Ecology, a niche (pronounced nich nēsh or nish A shorthand definition of niche is how an organism makes a living In Community ecology, the competitive exclusion principle, sometimes referred to as Gause's Law of competitive exclusion or just Gause's Law Loss of prey species may lead to coextinction of their predator. Coextinction of a Species is the loss of one species upon the Extinction of another In addition, because predators are found in higher trophic levels, they are less abundant and much more vulnerable to extinction.

Biological pest control

Main article: Biological pest control

Predators may be put to use in conservation efforts to control introduced species. Biological control of pests in Agriculture is a method of controlling pests (including Insects Mites Weeds and plant diseases Although the aim in this situation is to remove the introduced species entirely, keeping its abundance down is often the only possibility. Predators from its natural range may be introduced to control populations, though in some cases this has little effect, and may even cause unforeseen problems. Besides their use in conservation biology, predators are also important for controlling pests in agriculture. "Conservation Biology" redirects here For the Scientific journal, see Conservation Biology (journal. A pest is an organism which has characteristics that are regarded by Humans as injurious or unwanted Agriculture refers to the production of goods through the growing of plants and fungi and the raising of domesticated Animals The study of agriculture Natural predators are an environmentally friendly and sustainable way of reducing damage to crops, and are one alternative to the use of chemical agents such as pesticides. A pesticide is a substance or mixture of substances used to kill a pest.

See also

• Prey drive

References

External links

• Predator-Prey Equations by Eric W. Weisstein, The Wolfram Demonstrations Project.

Further reading

• Barbosa, P. and I. Castellanos (eds) 2004. Ecology of predator-prey interactions New York : Oxford University Press. 394 p. ISBN 0195171209
• Curio, E. 1976. The ethology of predation Berlin ; New York : Springer-Verlag. 250 p. ISBN 0387077200

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