- Predate redirects here. The verb "predate" may mean "[have a] date earlier than": see wikt:predate.
In
ecologyEcology is the interdisciplinary scientific study of the interactions between organisms and the interactions of these organisms with their environment....
,
predation describes a
biological interactionBiological 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 from its surroundings. It is part of its environment, rich in living and non-living elements, all of which interact with each...
where a
predator (an organism that is hunting) feeds on its
prey, (the organism that is attacked). Predators may or may not kill their prey prior to
feedingFeeding is the process by which organisms, typically animals, obtain food. Terminology often uses either the suffix -vore from Latin vorare, meaning 'to devour', or phagy, from Greek φαγειν, meaning 'to eat'....
on them, but the act of predation always results in the death of the prey. The other main category of
consumptionA Heterotroph is an organism that uses organic carbon for growth. This contrasts with autotrophs, such as plants, which are able to directly use sources of energy, such as light to produce organic substrates from inorganic carbon dioxide.- Ecology :Heterotrophs are known as consumers in food...
is
detritivoryDetritivores, also known as detritus feeders or saprophages, are heterotrophs that obtain nutrients by consuming detritus . By doing so, they contribute to decomposition and the nutrient cycles....
, the consumption of dead organic material (
detritusDetritus is a biological term used to describe dead or waste organic material.Detritus may also refer to:* Detritus , a geological term used to describe the particles of rock produced by weathering...
). It can at times be difficult to separate the two feeding behaviors, 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).
Selective pressures imposed on one another has led to an
evolutionary arms raceIn evolutionary biology, an evolutionary arms race is an evolutionary struggle between competing sets of co-evolving genes that develop adaptations and counter-adaptations against each other, resembling an arms race, which are also examples of positive feedback...
between prey and predator, resulting in various antipredator adaptations.
Classification of predators
The unifying theme in all classifications of predation is the predator lowering the
fitnessFitness is a central concept in evolutionary theory. It describes the capability of an individual of certain genotype to reproduce, and usually is equal to the proportion of the individual's genes in all the genes of the next generation...
of its prey, or put another way, it reduces its prey's chances of survival, reproduction, or both. Ways of classifying predation surveyed here include grouping by
trophic levelIn ecology, trophic dynamics is the system of trophic levels , which describes the position that an organism occupies in a food chain — what an organism eats, and what eats the organism.- Energy economy :...
or diet, by specialization, and by the nature of their interaction with prey.
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
hostIn biology, a host is an organism that harbors a parasite , or a mutual or commensal symbiont, typically providing nourishment and shelter. In botany, a host plant is one that supplies food resources and substrate for certain insects or other fauna...
). 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. Whereas other types of predator all harm their prey in some way, this form results in their certain death. Predators may hunt actively for prey, or sit and wait for prey to approach within striking distance, as in
ambush predatorAmbush predators or sit-and-wait predators are carnivorous animals that capture prey by stealth or cunning, not by speed or necessarily by strength. These organisms usually hide motionless and wait for prey to come within striking distance. They are often camouflaged, and may be solitary...
s. Some predators kill large prey and dismember or chew it prior to eating it, such as a
jaguarThe Jaguar, Panthera onca, is a big cat, a feline in the Panthera genus. It is the only Panthera species found in the Americas. The jaguar is the third-largest feline after the tiger and the lion, and the largest and most powerful feline in the Western Hemisphere...
, while others may eat their (usually much smaller) prey whole, as does a
bottlenose dolphinBottlenose dolphins, the genus Tursiops, are the most common and well-known members of the family Delphinidae, the family of oceanic dolphins. Recent molecular studies show the genus contains two species, the Common Bottlenose Dolphin and the Indo-Pacific Bottlenose Dolphin , where previous...
or any
snakeSnakes are elongate legless carnivorous reptiles of the suborder Serpentes that can be distinguished from legless lizards by their lack of eyelids and external ears. Like all squamates, snakes are ectothermic amniote vertebrates covered in overlapping scales...
, or a
duckDuck is the common name for a number of species in the Anatidae family of birds. The ducks are divided between several subfamilies listed in full in the Anatidae article; they do not represent a monophyletic group but a form taxon, since swans and geese are not considered ducks...
or
storkStorks are large, long-legged, long-necked wading birds with long stout bills, belonging to the family Ciconiidae. They are the only family in the biological order Ciconiiformes, which was once much larger and held a number of families....
swallowing a
frogFrogs are amphibians in the order Anura , formerly referred to as Salientia . Most frogs are characterized by long hind legs, a short body, webbed digits , protruding eyes and the absence of a tail...
. Some predation entails
venomVenom is any of a variety of toxins used by certain types of animals. Generally, venom is injected by such means as a bite or a sting.-The distinction between venom and poison:...
which subdues a prey creature before the predator ingests the prey by killing, which the
box jellyfishBox jellyfish, named for their cube-shaped medusae, are a class of invertebrates belonging to the class Cubozoa, as well as being the preferred common name for notoriously dangerous Chironex fleckeri.- Nomenclature :...
does, or disabling it, found in the behavior of the cone shell. In some cases the venom, as in
rattlesnakeRattlesnakes are a group of venomous snakes, genera Crotalus and Sistrurus. They belong to the subfamily of venomous snakes known commonly as pit vipers.-Overview:...
s and some
spiderSpiders are air-breathing chelicerate arthropods that have eight legs, and chelicerae modified into fangs that inject venom. They are the largest order of arachnids and rank seventh in total species diversity among all other groups of organisms...
s, contributes to the digestion of the prey item even before the predator begins eating. In other cases, the prey organism may die in the mouth or digestive system of the predator.
Baleen whaleThe baleen whales, also called whalebone whales or great whales, form the Mysticeti, one of two suborders of the Cetacea . Baleen whales are characterized by having baleen plates for filtering food from water, rather than having teeth. This distinguishes them from the other suborder of cetaceans,...
s, for example, eat millions of microscopic plankton at once, the prey being broken down well after entering the whale.
Seed predationSeed predation, often referred to as granivory, is a type of plant-animal interaction in which granivores feed on the seeds of plants as a main or exclusive food source , in many cases leaving the seeds damaged and not viable...
is another form of true predation, as
seedA seed , referred to as a kernel in some plants, is a small embryonic plant enclosed in a covering called the seed coat, usually with some stored food. It is the product of the ripened ovule of gymnosperm and angiosperm plants which occurs after fertilization and some growth within the mother plant...
s represent potential organisms. Predators of this classification need not eat prey entirely, for example some predators cannot digest
boneBones 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 red and white blood cells and store minerals. Bone tissue is a type of dense connective tissue...
s, while others can. 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. While some herbivores like
zooplanktonZooplankton are the heterotrophic type of plankton. Plankton are organisms drifting in the water column of oceans, seas, and bodies of fresh water. The name of zooplankton is derived from the Greek zoon , meaning "animal", and , meaning "wanderer" or "drifter"...
live on unicellular phytoplankton and have no choice but to kill their prey, many only eat a small part of the plant. Grazing livestock may pull some grass out at the roots, but most is simply grazed upon, allowing the plant to regrow once again.
Kelp{Taxobox| name =Kelp| image = Kelp In Freycinet Tasmania.jpg| image_width = 300px| image_caption = Kelp on rocky beach in Freycinet, Tasmania| regnum = Chromalveolata| phylum = Heterokontophyta| classis = Phaeophyceae| ordo = Laminariales...
is frequently grazed in subtidal kelp forests, but regrows at the base of the blade continuously to cope with browsing pressure. Animals may also be 'grazed' upon; female
mosquitoMosquito is a common insect in the family Culicidae...
s land on hosts briefly to gain sufficient
proteinProteins are organic compounds made of amino acids arranged in a linear chain and folded into a globular form. The amino acids in a polymer chain are joined together by the peptide bonds between the carboxyl and amino groups of adjacent amino acid residues...
s for the development of their offspring. Starfish may be grazed on, being capable of regenerating lost arms.
Parasitism
Parasites can at times be difficult to distinguish from grazers. 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
elephantElephants are large land mammals in two genera of the family Elephantidae: Elephas and Loxodonta. Three species of elephant are living today: the African Bush Elephant, the African Forest Elephant and the Asian 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. This close living arrangement may be described by the term
symbiosisThe term symbosis commonly describes close and often long-term interactions between different biological species...
, 'living together,' but unlike
mutualismMutualism is a biological interaction between two organisms, where each individual derives a fitness benefit . Similar interactions within a species are known as co-operation...
the association significantly reduces the
fitnessFitness is a central concept in evolutionary theory. It describes the capability of an individual of certain genotype to reproduce, and usually is equal to the proportion of the individual's genes in all the genes of the next generation...
of the host. Parasitic organisms range from the macroscopic
mistletoeMistletoe is the common name for a group of hemi-parasitic plants in the order Santalales that grow attached to and within the branches of a tree or shrub...
, a
parasitic plantA parasitic plant is one that derives some or all of its sustenance from another plant. About 4,100 species in approximately 19 families of flowering plants are known. Parasitic plants have a modified root, the haustorium, that penetrates the host plant and connects to the xylem, phloem, or both....
, to microscopic internal parasites such as
choleraCholera, sometimes known as Asiatic or epidemic cholera, is an infectious gastroenteritis caused by enterotoxin-producing strains of the bacterium Vibrio cholerae. Transmission to humans occurs through eating food or drinking water contaminated with Vibrio cholerae from other cholera patients...
. Some species however have more loose associations with their hosts.
LepidopteraLepidoptera is an order of insects that includes moths and butterflies. It is one of the most speciose orders in the class Insecta, encompassing moths and the three superfamilies of butterflies, skipper butterflies, and moth-butterflies...
(
butterflyA butterfly is an insect of the order Lepidoptera. Like all Lepidoptera, butterflies are notable for their unusual life cycle with a larval caterpillar stage, an inactive pupal stage, and a spectacular metamorphosis into a familiar and colourful winged adult form. Most species are day-flying so...
and
mothA moth is an insect closely related to the butterfly, both being of the order Lepidoptera. The differences between butterflies and moths are more than just taxonomy. Sometimes the names "Rhopalocera" and "Heterocera" are used to formalize the popular distinction...
) larvae may feed parasitically on only a single plant, or they may graze on several nearby plants. 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. 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 waspThe Ichneumonoidea are insects classified in the hymenopteran suborder Apocrita. The superfamily is made up of the ichneumon wasps and the braconids...
s, 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 systemThe nervous system is a network of specialized cells that communicate information about an organism's surroundings and itself. It processes this information and causes reactions in other parts of the body. It is composed of neurons and other specialized cells called glial cells that aid in the...
resulting in prey death. 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 Hymenoptera is one of the largest orders of insects, comprising the sawflies, wasps, bees, and ants. The name refers to the heavy wings of the insects, and is derived from the Ancient Greek ὑμήν : membrane and πτερόν : wing...
, Diptera and Coleoptera parasitoids make up as much as 10% of all insect species.
Degree of specialization
Among predators there is a large degree of specialization. Many predators specialize in hunting only one species of prey. Others are more opportunistic and will kill and eat almost anything (examples:
humanHumans are bipedal primates belonging to the species Homo sapiens in Hominidae, the great ape family. They are the only surviving member of the genus Homo. Humans have a highly developed brain, capable of abstract reasoning, language, introspection, and problem solving...
s,
leopardThe leopard , Panthera pardus, is a member of the Felidae family and the smallest of the four "big cats" in the genus Panthera; the other three being the tiger, lion and jaguar...
s, and
dogThe dog is a domesticated form of the Gray Wolf, a member of the Canidae family of the order Carnivora. The term is used for both feral and pet varieties. The domestic dog has been one of the most widely kept working and companion animals in human history...
s). 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 raceIn evolutionary biology, an evolutionary arms race is an evolutionary struggle between competing sets of co-evolving genes that develop adaptations and counter-adaptations against each other, resembling an arms race, which are also examples of positive feedback...
and tends to keep the populations of both species in equilibrium. 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
scavengingScavenging, or necrophagy, is a carnivorous feeding behaviour in which a predator consumes corpses or carrion that were not killed to be eaten by the predator or others of its species. Scavengers play an important role in the ecosystem by contributing to the decomposition of dead animal remains...
or a herbivorous diet if possible.
Trophic level
Predators are often another organism's prey, and likewise prey are often predators. Though
blue jayThe Blue Jay is a passerine bird, and a member of the family Corvidae native to North America. It belongs to the "blue", Canadian or American jays, which are, among the Corvidae, not closely related to other jays...
s prey on
insectInsects are arthropods, having a hard exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae. They are the most diverse group of animals on the planet and include more than a million species that are already described. Insects represent more than half of all...
s, they may in turn be prey for
catThe cat , also known as the domestic cat or housecat to distinguish it from other felines and felids, is a small carnivorous mammal that is valued by humans for its companionship and its ability to hunt vermin and household pests...
s and
snakeSnakes are elongate legless carnivorous reptiles of the suborder Serpentes that can be distinguished from legless lizards by their lack of eyelids and external ears. Like all squamates, snakes are ectothermic amniote vertebrates covered in overlapping scales...
s, which, in the latter's case, may themselves be the prey of
hawkThe term hawk can be used in several ways:* In strict usage in Europe and Asia, to mean any of the species in the subfamily Accipitrinae, which comprises the genera Accipiter, Micronisus, Melierax, Urotriorchis and Megatriorchis. The large and widespread Accipiter genus includes goshawks,...
s. One way of classifying predators is by
trophic levelIn ecology, trophic dynamics is the system of trophic levels , which describes the position that an organism occupies in a food chain — what an organism eats, and what eats the organism.- Energy economy :...
. Organisms which feed on
autotrophAn autotroph is an organism that produces complex organic compounds from simple inorganic molecules using energy from light or inorganic chemical reactions....
s, the producers of the trophic pyramid, are known as
herbivoreA herbivore is an animal that is adapted to eat plants and not meat.Herbivory is a form of predation in which an organism consumes principally autotrophs such as plants, algae and photosynthesizing bacteria....
s or
primary consumers; those that feed on
heterotrophA Heterotroph is an organism that uses organic carbon for growth. This contrasts with autotrophs, such as plants, which are able to directly use sources of energy, such as light to produce organic substrates from inorganic carbon dioxide.- Ecology :Heterotrophs are known as consumers in food...
s such as animals are known as
secondary consumers. Secondary consumers are a type of
carnivoreA carnivore , meaning 'meat eater' , is an animal that derives its energy and nutrient requirements from a diet consisting mainly or exclusively of vertebrate and/or invertebrate animal tissue, whether through predation or scavenging...
, but there are also tertiary consumers eating these carnivores, quartary consumers eating them, and so forth. 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, and may go only as high as three trophic levels (for example, a
lionThe Lion is one of four big cats in the genus Panthera, and a member of the family Felidae. With some males exceeding 250 kg in weight, it is the second-largest living cat after the tiger...
that preys upon large herbivores such as
wildebeestThe wildebeest , also called the gnu , is an antelope of the genus Connochaetes. It is a hooved mammal. Wildebeest is Dutch for wild beast....
which in turn eat
grassGrasses, or more technically graminoids, are monocotyledonous, usually herbaceous plants with narrow leaves growing from the base. They include the "true grasses", of the Poaceae family, as well as the sedges and the rushes . The true grasses include cereals, bamboo and the grasses of lawns...
es). A predator at the top of any
food chainFood chains describe the eating relationships between species within an ecosystem or a particular living place. Many types of food chains or webs are applicable depending on habitat or environmental factors...
(that is, one that is preyed upon by no organism) is called an
apex predatorApex predators is a predator that has virtually no predators of its own, residing at the top of its food chain...
; examples include the
orcaThe Killer Whale or Orca , or less commonly, Blackfish, is the largest species of the dolphin family. Most people think that they are whales, but they are actually dolphins. They are called killer whales often because they sometimes hunt whales for food...
,
sperm whaleThe sperm whale, , is a species of marine mammal in the order cetacea, a toothed whale with the largest brain of any animal. The whale was named after the milky-white waxy substance, spermaceti, found in its head and originally mistaken for sperm...
,
anacondaAnaconda is a large, non-venomous snake found in tropical South America. They are found mostly in water, such as the Amazon River. Although the name actually applies to a group of snakes, it is often used to refer only to one species in particular, the common or green anaconda, Eunectes murinus,...
,
Komodo dragonThe Komodo dragon is a species of lizard that inhabits the islands of Komodo, Rinca, Flores, and Gili Motang in Indonesia. A member of the monitor lizard family , it is the largest living species of lizard, growing to an average length of and weighing around...
,
tigerThe tiger is a member of the Felidae family; the largest of the four "big cats" in the genus Panthera. Native to much of eastern and southern Asia, the tiger is an apex predator and an obligate carnivore...
,
bald eagleThe Bald Eagle is a bird of prey found in North America that is most recognizable as the national bird and symbol of the United States of America. This sea eagle has two known sub-species and forms a species pair with the White-tailed Eagle. Its range includes most of Canada and Alaska, all of the...
, and
Nile crocodileThe Nile Crocodile is an African crocodile which is common in Somalia, Ethiopia, Kenya, and Zambia.-Distribution and habitat:...
-- and even omnivorous humans and
grizzly bearThe grizzly bear , also known as the silvertip bear, is a subspecies of brown bear that generally lives in the uplands of western North America....
s. An apex predator in one environment may not retain this position as a top predator if introduced to another habitat, such as a
dogThe dog is a domesticated form of the Gray Wolf, a member of the Canidae family of the order Carnivora. The term is used for both feral and pet varieties. The domestic dog has been one of the most widely kept working and companion animals in human history...
among
alligatorThe American Alligator, Alligator mississippiensis, is one of the two living species of Alligator, a genus within the family Alligatoridae. The American Alligator is native only to the Southeastern United States, where it inhabits wetlands that frequently overlap with human-populated areas...
s or a
snapping turtleThe Common Snapping Turtle is a large freshwater turtle of the family Chelydridae. Its natural range extends from southeastern Canada south, west to the Rocky Mountains , throughout Mexico, and as far south as Ecuador...
among
jaguarThe Jaguar, Panthera onca, is a big cat, a feline in the Panthera genus. It is the only Panthera species found in the Americas. The jaguar is the third-largest feline after the tiger and the lion, and the largest and most powerful feline in the Western Hemisphere...
s; a predatory species introduced into an area where it faces no predators, such as a domestic cat or a
pigPigs are a genus of even-toed ungulates within the family Suidae. The name hog most commonly refers to the domestic pig in everyday parlance, but technically encompasses several distinct species, including the wild boar...
in some insular environments, can become an apex predator by default.
Many organisms (of which humans are prime examples) eat from multiple levels of the food chain and thus make this classification problematic. 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
omnivoreOmnivores are species that eat both plants and animals as their primary food source...
s. Even such herbivores such as the
giant pandaThe Giant Panda is a mammal native to central-western and south western China. The Giant Panda is a member of the Ursidae family. It is easily recognized by its large, distinctive black patches around the eyes, over the ears, and across its round body...
may supplement their diet with meat.
ScavengingScavenging, or necrophagy, is a carnivorous feeding behaviour in which a predator consumes corpses or carrion that were not killed to be eaten by the predator or others of its species. Scavengers play an important role in the ecosystem by contributing to the decomposition of dead animal remains...
of carrion provides a significant part of the diet of some of the most fearsome predators.
Carnivorous plantCarnivorous plants are plants that derive some or most of their nutrients from trapping and consuming animals or protozoans, typically insects and other arthropods. Carnivorous plants appear adapted to grow in places where the soil is thin or poor in nutrients, especially nitrogen, such as acidic...
s would be very difficult to fit into this classification, producing their own food but also digesting anything that they may trap. Organisms which eat
detritivoreDetritivores, also known as detritus feeders or saprophages, are heterotrophs that obtain nutrients by consuming detritus . By doing so, they contribute to decomposition and the nutrient cycles....
s or parasites would also be difficult to classify by such a scheme.
Predation as competition
An alternative view offered by
Richard DawkinsClinton Richard Dawkins, FRS, FRSL is a British ethologist, zoologist, Neo-Darwinian evolutionary biologist and theorist and a popular science author....
is of predation as a form of
competitionCompetition can be defined as an Biological interaction structure. Competition among members of the same species is known as intraspecific competition, while competition between individuals of different species is known as interspecific competition...
: the
geneA gene is the basic unit of heredity in a living organism. All living things depend on genes. Genes hold the information to build and maintain their cells and pass genetic traits to offspring...
s of both the predator and prey are competing for the body (or 'survival machine') of the prey organism. This is best understood in the context of the gene centered view of evolution.
Ecological role
Predators may increase the
biodiversityBiodiversity is the variation of life forms within a given ecosystem, biome, or for the entire Earth. Biodiversity is often used as a measure of the health of biological systems...
of communities by preventing a single species from becoming dominant. Such predators are known as
keystone speciesA keystone species is a species that has a disproportionate effect on its environment relative to its abundance. Such species affect many other organisms in an ecosystem and help to determine the types and numbers of various others species in a community....
and may have a profound influence on the balance of organisms in a particular
ecosystemAn ecosystem is a system of interdependent organisms which share the same habitat, in an area functioning together with all of the physical factors of the environment. Ecosystems can be permanent or temporary. Ecosystems usually form a number of food webs...
. 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.
The elimination of wolves from Yellowstone National Park had profound impacts on the trophic pyramid. Without predation, herbivores began to over-graze many woody brow species, affecting the area's plant populations. Additionally, wolves often kept animals from grazing in riparian areas, which protected beavers from having their food sources encroached upon. The removal of wolves had a direct effect on beaver populations, as their habitat became territory for grazing.
Furthermore, predation keeps hydrological features such as creeks and streams in normal working order. Increased browsing on willows lenr and conifers along Blacktail Creek due to a lack of predation resulted in channel incision because those species helped slow the water down and hold the soil in place.
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. 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, though the individuals preyed upon themselves do not benefit. This means that, at each applicable stage, predator and prey species are in an
evolutionary arms raceIn evolutionary biology, an evolutionary arms race is an evolutionary struggle between competing sets of co-evolving genes that develop adaptations and counter-adaptations against each other, resembling an arms race, which are also examples of positive feedback...
to maximize their respective abilities to obtain food or avoid being eaten. This interaction has resulted in a vast array of
adaptationAdaptation is the process whereby a population becomes better suited to its habitat. This process takes place over many generations, and is one of the basic phenomena of biology....
s in both groups.
One adaptation helping both predators and prey avoid detection is
camouflageCamouflage is a method of crypsis that allows an otherwise visible organism or object to remain indiscernible from the surrounding environment through deception. Examples include a tiger's stripes and the battledress of a modern soldier...
, a form of
crypsisIn ecology, crypsis is the ability of an organism to avoid observation. A form of antipredator adaptation, methods range from camouflage, nocturnality, subterranean lifestyle, transparency, or mimicry...
where species have an appearance which helps them blend into the background. 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.g.
zebraZebras are African equids best known for their distinctive white and black stripes. Their stripes come in different patterns unique to each individual. They are generally social animals and can be seen in small harems to large herds. In addition to their stripes, zebras have erect, mohawk-like manes...
s' stripes blend in with each other in a herd, making it difficult for
lionThe Lion is one of four big cats in the genus Panthera, and a member of the family Felidae. With some males exceeding 250 kg in weight, it is the second-largest living cat after the tiger...
s to focus on a single target). The more convincing camouflage is, the more likely it is that the organism will go unseen.
MimicBiological mimicry occurs when a group of organisms, the mimics, have evolved to share common perceived characteristics with another group, the models, through the selective action of a signal-receiver or dupe. Collectively this is known as a mimicry complex. The model is usually another species...
ry is a related phenomenon where an organism has a similar appearance to another species. One such example is the drone fly, which looks a lot like a
beeBees are flying insects closely related to wasps and ants, and are known for their role in pollination and for producing honey and beeswax. Bees are a monophyletic lineage within the superfamily Apoidea, presently classified by the unranked taxon name Anthophila...
, yet is completely harmless as it cannot sting at all. Another example of batesian mimicry is the
io mothThe Io Moth is a very colorful North American moth in the Saturniidae family. It ranges from the southeast corner of Manitoba and in the southern extremes of Ontario, Quebec, and New Brunswick in Canada, and in the US it is found from North Dakota, South Dakota, Nebraska, Colorado, New Mexico,...
, (
Automeris io), which has markings on its wings which resemble an owl's eyes. 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
firefliesLampyridae is a family of insects in the beetle order Coleoptera. They are winged beetles, and commonly called fireflies or lightning bugs for their conspicuous crepuscular use of bioluminescence to attract mates or prey. Fireflies are capable of producing a "cold light", containing no ultraviolet...
of the genus
PhoturisPhoturis is a genus of fireflies wherein are the femme fatale fireflies of North America. This common name refers to the fact that the females of these predatory beetles mimic the light signals of other firefly species' males, to attract, kill, and eat them...
, for example, copy the light signals of other species, thereby attracting male fireflies which are then captured and eaten (see
aggressive mimicryAggressive mimicry is a form of mimicry where predators, parasites or parasitoids share similar signals with a harmless model, allowing them to avoid being correctly identified by their prey or host...
).
Predator
While successful
predation results in a gain of
energyBiological thermodynamics is a phrase that is sometimes used to refer to bioenergetics, the study of energy transformation in the biological sciences...
, hunting invariably involves energetic costs as well. When
hungerHunger is a feeling experienced when one has a desire to eat. Satiety is the absence of hunger. The often unpleasant feeling of hunger originates from the hypothalamus releasing hormones that target receptors in the liver...
is not an issue, most predators will generally not seek to attack prey since the costs outweight the benefits. For instance, a large
predatory fishPredatory fish are fish that predate upon other fish or animals. Some predatory fish include perch, muskie , pike, walleye, salmon.Levels of large predatory fish in the global oceans are estimated to be about 10% of their pre-industrial levels...
like a
sharkSharks are a type of fish with a full cartilaginous skeleton and a highly streamlined body. The earliest known sharks date from more than 420 million years ago, before the time of the dinosaurs....
that is well fed in an
aquariumAn aquarium is a vivarium consisting of at least one transparent side in which water-dwelling plants or animals are kept. Fishkeepers use aquaria to keep fish, invertebrates, amphibians, marine mammals, turtles, and aquatic plants...
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).
Surplus killingSurplus killing is the behavior predators exhibit when they kill more prey than they can immediately use. They may partially consume, cache, or abandon intact prey...
represents a deviation from this type of behaviour. The treatment of consumption in terms of
cost-benefit analysisCost-benefit analysis is a term that refers both to:* helping to appraise, or assess, the case for a project or proposal, which itself is a process known as project appraisal; and* an informal approach to making decisions of any kind....
is known as
optimal foraging theoryA central concern of ecology has traditionally been foraging behavior. In its most basic form, optimal foraging theory states that organisms forage in such a way as to maximize their energy intake per unit time. In other words, they behave in such a way as to find, capture and consume food...
, and has been quite successful in the study of animal behavior. Costs and benefits are generally considered in energy gain per unit time, though other factors are also important, such as
essential nutrientAn essential nutrient is a nutrient required for normal body functioning that either cannot be synthesized by the body at all, or cannot be synthesized in amounts adequate for good health , and thus must be obtained from a dietary source. Some categories of essential nutrients include vitamins,...
s that have no caloric value but are necessary for survival and health.
Social Predation offers the possibility of predators to kill creatures larger than those that members of the species could overpower singly.
LionThe Lion is one of four big cats in the genus Panthera, and a member of the family Felidae. With some males exceeding 250 kg in weight, it is the second-largest living cat after the tiger...
s,
hyenaThe Hyaenidae is a mammalian family of order Carnivora. The Hyaenidae family, native to both African and Asian continents, consists of four living species, the Striped Hyena and Brown Hyena , the Spotted Hyena , and the Aardwolf .-Evolution:Hyenas seem to have originated 26 million years ago from...
s, wolves,
dholeThe Dhole , also known as the Asiatic Wild Dog, Indian Wild Dog, or Red Dog, is a species of Asian canid, and the only member of the genus Cuon.-Description:...
s,
African wild dogThe African Wild Dog is a carnivorous mammal of the Canidae family, found only in Africa, especially in scrub savanna and other lightly wooded areas...
s, and
piranhaA piranha or piraña is a member of a family of omnivorous freshwater fish which live in South American rivers. In Venezuelan rivers, they are called caribes. They are known for their sharp teeth and a voracious appetite for meat....
s can kill large herbivores that single animals of the same species could never dispatch. Social predation allows some animals to organize
huntsHunting is the practice of pursuing living animals for food, recreation, or trade. In present-day use, the term refers to lawful hunting, as distinguished from poaching, which is the killing, trapping or capture of the hunted species contrary to applicable law...
of creatures that would easily escape a single predator; thus
chimpanzeeChimpanzee, sometimes colloquially chimp, is the common name for the two extant species of ape in the genus Pan. The Congo River forms the boundary between the native habitat of the two species:...
s can prey upon colubus monkeys, and
harrier hawkThe Harrier Hawk, African Harrier Hawk or Gymnogene is a bird of prey. It is about 60–66 cm in length, and is related to the harriers. It breeds in most of Africa south of the Sahara. The only other member of the genus is the allopatric Madagascar Harrier Hawk.Its habitat is woodland...
s can cut off all possible escapes for a doomed rabbit. Extreme specialization of roles is evident in some hunting that requires co-operation between predators of very different species:
humanHumans are bipedal primates belonging to the species Homo sapiens in Hominidae, the great ape family. They are the only surviving member of the genus Homo. Humans have a highly developed brain, capable of abstract reasoning, language, introspection, and problem solving...
s with the aid of
falconA falcon is any species of raptor in the genus Falco. The word comes from their Latin name falco, related to Latin falx because of the shape of these birds' wings.-Overview:...
s or
dogThe dog is a domesticated form of the Gray Wolf, a member of the Canidae family of the order Carnivora. The term is used for both feral and pet varieties. The domestic dog has been one of the most widely kept working and companion animals in human history...
s, or fishing with
cormorantThe bird family Phalacrocoracidae is represented by some 40 species of cormorants and shags. Several different classifications of the family have been proposed recently, and the number of genera is disputed.- Names :...
s or dogs. Social predation is often very complex behavior, and not all social creatures (for example, domestic cats) perform it. Even without complex intelligence but instinct alone, some ant species can destroy much-larger creatures.
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. 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.
It has been observed that well-fed predator animals in a lax captivity (for instance,
petA pet is an animal kept for companionship and enjoyment or a household animal, as opposed to livestock, laboratory animals, working animals or sport animals, which are kept for economic reasons. The most popular pets are noted for their loyal or playful characteristics, for their attractive...
or
farmA farm is an area of land, including various structures, devoted primarily to the practice of producing and managing food , fibers and, increasingly, fuel. It is the basic production facility in food production. Farms may be owned and operated by a single individual, family, community, corporation...
animals) will usually differentiate between putative prey animals who are familiar co-inhabitants in the same human area from wild ones outside the area. 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
catThe cat , also known as the domestic cat or housecat to distinguish it from other felines and felids, is a small carnivorous mammal that is valued by humans for its companionship and its ability to hunt vermin and household pests...
s and pet
miceA mouse is a small mammal belonging to the order of rodents. The best known mouse species is the common house mouse . It is also a popular pet. The American white-footed mouse and the deer mouse also sometimes live in houses. In some places, certain kinds of field mice are also common...
, for example, may live together in the same human residence without incident as companions. Pet cats and pet
dogThe dog is a domesticated form of the Gray Wolf, a member of the Canidae family of the order Carnivora. The term is used for both feral and pet varieties. The domestic dog has been one of the most widely kept working and companion animals in human history...
s under human mastership often depend on each other for warmth, companionship, and even protection, particularly in rural areas.
Antipredator adaptations
Antipredator adaptations have evolved in prey populations due to the selective pressures of predation over long periods of time.
Aggression
Predatory animals often use their usual methods of attacking prey to inflict or to threaten grievous injury to their own predators. The
electric eelThe electric eel or temblador , is an electrical fish, and the only species of the genus Electrophorus. It is capable of generating powerful electric shocks, which it uses for both hunting and self-defense. It is an apex predator in its South American range...
uses the same electrical current to kill prey and to defend itself against animals (
anacondaAnaconda is a large, non-venomous snake found in tropical South America. They are found mostly in water, such as the Amazon River. Although the name actually applies to a group of snakes, it is often used to refer only to one species in particular, the common or green anaconda, Eunectes murinus,...
s, caimans,
jaguarThe Jaguar, Panthera onca, is a big cat, a feline in the Panthera genus. It is the only Panthera species found in the Americas. The jaguar is the third-largest feline after the tiger and the lion, and the largest and most powerful feline in the Western Hemisphere...
s,
egretAn egret is any of several herons, most of which are white or buff, and several of which develop fine plumes during the breeding season. Many egrets are members of the genera Egretta or Ardea which contain other species named as herons rather than egrets...
s, cougars,
giant otterThe Giant Otter is a South American carnivorous mammal. It is the longest member of the Mustelidae, or weasel family, a globally successful group of predators. Unusually for a mustelid, the Giant Otter is a social species, with family groups typically supporting three to eight members...
s, humans, and dogs) that ordinarily prey upon fish similar to an electric eel in size; the electric eel thus remains an apex predator in a predator-rich environment. Many non-predatory prey animals, such as a
zebraZebras are African equids best known for their distinctive white and black stripes. Their stripes come in different patterns unique to each individual. They are generally social animals and can be seen in small harems to large herds. In addition to their stripes, zebras have erect, mohawk-like manes...
, can give a strong kick that can maim or kill, while others charge with tusks or horns.
Mobbing behavior
Mobbing behaviorMobbing behavior is an antipredator behavior which occurs when individuals of a certain species mob a predator by cooperatively attacking or harassing it, usually in order to protect their offspring. A simple definition of mobbing is an assemblage of individuals around a potentially dangerous...
occurs when a species turns the tables on their predator by
cooperativelyCo-operation or co-operative behaviours are terms used to describe behaviours by organisms which are beneficial to other members of the same species. There are several competing theories which help to explain why natural selection favours some types of co-operative behaviour...
attacking or harassing it. This is most frequently seen in
birdBirds are winged, bipedal, endothermic , vertebrate animals that lay eggs. There are around 10,000 living species, making them the most numerous tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Birds range in size from the Bee Hummingbird to the ...
s, though it is also known to occur in other social animals. For example, nesting
gullGulls are birds in the family Laridae. They are most closely related to the terns and only distantly related to auks, skimmers, and more distantly to the waders...
colonies are widely seen to attack intruders, including humans. Costs of mobbing behavior include the risk of engaging with predators, as well as energy expended in the process, but it can aid the survival of members of a species.
MockingbirdMockingbirds are a group of New World passerine birds from the Mimidae family. They are best known for the habit of some species mimicking the songs of insect and amphibian sounds as well as other bird songs, often loudly and in rapid succession. There are about 17 species in three genera...
s can effectively force a cat or dog to seek something less troublesome through mobbing behavior. One mockingbird might fly in front of the cat or dog, enticing a common predator upon birds to lunge, while another pecks at the cat or dog from behind to inflict a sharp pain that forces the predator to hesitate when it encounters mockingbirds.
While mobbing has
evolved independentlyConvergent evolution describes the acquisition of the same biological trait in unrelated lineages.The wing is a classic example of convergent evolution in action. Although their last common ancestor did not have wings, birds and bats do, and are capable of powered flight. The wings are similar in...
in many species, it only tends to be present in those whose young are frequently preyed on, especially birds. It may complement
crypticIn ecology, crypsis is the ability of an organism to avoid observation. A form of antipredator adaptation, methods range from camouflage, nocturnality, subterranean lifestyle, transparency, or mimicry...
behavior in the offspring themselves, such as camouflage and hiding. 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.
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 GullThe Black-headed Gull is a small gull which breeds in much of Europe and Asia, and also in coastal eastern Canada. Most of the population is migratory, wintering further south, but some birds in the milder westernmost areas of Europe are resident...
s are one species which aggressively engages intruding predators, such as
Carrion CrowThe Carrion Crow is a member of the passerine order of birds and the crow family which is native to western Europe and eastern Asia.-Taxonomy:...
s. 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. 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
A
Thomson's GazelleThe Thomson's gazelle is one of the best-known gazelles. It is named after explorer Joseph Thomson and, as a result, is sometimes referred to as a "tommie"...
seeing a predator approach may start to run away, but then slow down and
stot.
StottingStotting is a gait of quadrupeds, particularly gazelles , involving jumping high into the air by lifting all four feet off the ground simultaneously. This may occur during pursuit by a predator. It might also occur during play...
is jumping into the air with the legs straight and stiff, and the white rear fully visible. Stotting is maladaptive for outrunning predators; evidence suggests that stotting
signalAnimal communication is any behavior on the part of one animal that has an effect on the current or future behaviour of another animal. The study of animal communication, sometimes called spencerology has played an important part in the methodology of ethology, sociobiology, and the study of animal...
s an unprofitable chase. 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.
AposematismAposematism , perhaps most commonly known in the context of warning colouration, describes a family of antipredator adaptations where a warning signal is associated with the unprofitability of a prey item to potential predators...
, 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
poisonIn the context of biology, poisons are substances that can cause disturbances to organisms, usually by chemical reaction or other activity on the molecular scale, when a sufficient quantity is absorbed by an organism...
ous, or able to harm them physically. Aposematic coloring involves bright, easily recognizable and unique colors and patterns. Upon being harmed (e.g. stung) by their prey, the appearance in such an organism will be
rememberedIn psychology, memory is an organism's mental ability to store, retain, and recall information. Traditional studies of memory began in the fields of philosophy, including techniques of artificially enhancing the memory....
as something to avoid.
Terrain Fear Factor
The "terrain fear factor" is an idea which assesses the risks associated with predator/prey encounters. This idea suggests that prey will change their usual habits to adjust to the terrain and its effect on the species' predation. For example, a species may forage in a terrain with a lower predation risk as opposed to one with high predation risk.
Population dynamics
It is fairly clear that predators tend to lower the survival and
fecundityFecundity, derived from the word fecund, generally refers to the ability to reproduce. In biology and demography, fecundity is the potential reproductive capacity of an organism or population, measured by the number of gametes , seed set or asexual propagules. Fecundity is under both genetic and...
of their prey, but on a higher level of organization,
populationIn biology, a population is the collection of inter-breeding organisms of a particular species; in sociology, a collection of human beings. Individuals within a population share a factor may be reduced by statistical means, but such a generalization may be too vague to imply anything...
s of predator and prey species also interact. 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 capacityThe carrying capacity of a biological species in an environment is the population size of the species that the environment can sustain indefinitely, given the food, habitat, water and other necessities available in the environment...
.
The
population dynamicsPopulation dynamics is the branch of life sciences that studies short- and long-term changes in the size and age composition of populations, and the biological and environmental processes influencing those changes...
of predator-prey interactions can be modelled using the Lotka–Volterra equations. These provide a
mathematical modelA mathematical model uses mathematical language to describe a system. Mathematical models are used not only in the natural sciences and engineering disciplines but also in the social sciences ; physicists, engineers, computer scientists, and economists use...
for the cycling of predator and prey populations.
Evolution of predation
Predation appears to have become a major selection pressure shortly before the
CambrianThe Cambrian is the first geological period of the Paleozoic era, lasting from ; it is succeeded by the Ordovician. Its subdivisions, and indeed its base, are somewhat in flux...
period—around —as evidenced by the almost simultaneous development of calcification in animals and algae, and predation-avoiding burrowing. However, predators had been grazing on micro-organisms since at least .
As predators
In much of the world, humans are the largest, best-organized, most cunning, and most powerful predators. The closest rival to humans in those characteristics in most of the world, the dog, is far more likely a collaborator than a competitor or a menace.
Humans are clever exploiters of tools from
snareA snare is a kind of trap used for capturing animals. It may also mean:* Snare drum* SNARE , a family of proteins involved in vesicle fusion* The Snares, a group of islands approximately 200 kilometres south of New Zealand...
s, clubs,
spearA spear is a pole weapon consisting of a shaft, usually of wood, with a sharpened head. The head may be simply the sharpened end of the shaft itself, as is the case with bamboo spears, or it may be of another material fastened to the shaft, such as obsidian, iron or bronze...
s, fishing gear,
firearmA firearm is a device which projects either single or multiple projectiles at high velocity through a controlled explosion. The firing is achieved by the gases produced through rapid, confined burning of a propellant. This process of rapid burning is technically known as deflagration...
s to boats and motor vehicles in hunting other animals. Humans even use other animals (dogs,
cormorantThe bird family Phalacrocoracidae is represented by some 40 species of cormorants and shags. Several different classifications of the family have been proposed recently, and the number of genera is disputed.- Names :...
s, and
falconA falcon is any species of raptor in the genus Falco. The word comes from their Latin name falco, related to Latin falx because of the shape of these birds' wings.-Overview:...
s) in hunting or fishing and such non-predatory animals as horses, camels, and elephants in getting approaches to prey.
Humans have reshaped huge expanses of the world as ranges and farms for the raising of livestock, poultry, and
fishFish farming is the principal form of aquaculture, while other methods may fall under mariculture. Fish farming involves raising fish commercially in tanks or enclosures, usually for food. A facility that releases juvenile fish into the wild for recreational fishing or to supplement a species'...
to be eaten as meat.
In conservation
Predators are an important consideration in matters relating to conservation.
IntroducedAn introduced, alien, exotic, non-indigenous, or non-native species, or simply an introduction, is a species living outside its native distributional range, which has arrived there by human activity, either deliberate or accidental...
predators may prove too much for populations which have not coevolved with them, leading to possible
extinctionIn biology and ecology, extinction is the end of an organism or group of taxa. The moment of extinction is generally considered to be the death of the last individual of that species...
. 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 responseFunctional response is a term in ecology that describes the relationship between prey and predators. There are three types of functional responses that are determined by relative abundances of both prey and predators.- Type I :...
, while still eating the last remaining prey organisms. 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, especially apex predators who are often in competition with humans.
CompetitionInterspecific competition, in ecology, is a form of competition in which individuals of different species vie for the different resource in an ecosystem...
for prey from other species could prove the end of a predator—if their
ecological nicheIn ecology, a niche is a term describing the relational position of a species or population in its ecosystem to each other; e.g. a dolphin could potentially be in another ecological niche from one that travels in a different school if the members of these schools utilize significantly different...
overlaps completely with that of another the
competitive exclusion principleIn community ecology, the competitive exclusion principle, sometimes referred to as Gause's Law of competitive exclusion or just Gause's Law, is a proposition which states that two species competing for the same resources cannot stably coexist if other ecological factors are constant...
requires only one can survive. Loss of prey species may lead to
coextinctionCoextinction of a species is the loss of one species upon the extinction of another. The term was originally used in the context of the extinction of parasitic insects following the loss of their specific hosts. The term is now used to describe the subsequent loss of any interacting species,...
of their predator. In addition, because predators are found in higher trophic levels, they are less abundant and much more vulnerable to extinction.
Biological pest control
Predators may be put to use in conservation efforts to control introduced species. 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 biologyConservation biology is the scientific study of the nature and status of Earth's biodiversity with the aim of protecting species, their habitats, and ecosystems from excessive rates of extinction. It is an interdisciplinary subject drawing on sciences, economics, and the practice of natural...
, predators are also important for controlling pests in
agricultureAgriculture is the production of food and goods through farming and forestry. Agriculture was the key development that led to the rise of human civilization, with the husbandry of domesticated animals and plants creating food surpluses that enabled the development of more densely populated and...
. 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
pesticideA pesticide is a substance or mixture of substances used to kill a pest.A pesticide is any substance or mixture of substance intended for:- preventing, destroying, repelling or mitigating any pest....
s.
See also
- Overpopulation in wild animals
Overpopulation in wild animals is a scenario in which the population of a wild species exceeds the carrying capacity of its ecological niche. Overpopulation is not a function of the number or density of the individuals, but rather the number of individuals compared to the resources they need to...
- Prey drive
Prey drive is the instinctive behavior of a carnivore to pursue and capture prey.In dog training, prey drive can be used as an advantage because dogs with strong prey drive are also willing to pursue moving objects such as toys, which can then be used to encourage certain kinds of behavior, such as...
- Bird of prey
Birds of prey are birds that hunt for food primarily on the wing, using their keen senses, especially vision. They are defined as any bird that kills its prey with its talons. Their talons and beaks tend to be relatively large, powerful and adapted for tearing and/or piercing flesh. In most cases,...
Further reading
- Barbosa, P. and I. Castellanos (eds.) (2004). Ecology of predator-prey interactions. New York: Oxford University Press. ISBN 0195171209.
- Curio, E. (1976). The ethology of predation. Berlin; New York: Springer-Verlag. ISBN 0387077200.
External links