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The term territory is also used in politics. Image File history File links Please see the file description page for further information. ... An intruder may refer to: An American military aircraft the Grumman A-6 Intruder A person or animal that enters territory that does not belong to them. ... A territory is a defined area (including land and waters), usually considered to be a possession of an animal, person, organization, or institution. ...

In ethology, sociobiology and behavioral ecology, the term territory refers to any geographical area that an animal of a particular species consistently defends against conspecifics (and, occasionally, animals of other species). Animals that defend territories in this way are referred to as territorial. Ethology is the scientific study of animal behaviour considered as a branch of zoology. ... Sociobiology is a synthesis of scientific disciplines that attempts to explain behavior in all species by considering the evolutionary advantages of social behaviors. ... Behavioural ecology is the study of the ecological and evolutionary basis for animal behavior, and the roles of behavior in enabling an animal to adapt to its environment (both intrinsic and extrinsic). ... Phyla Porifera (sponges) Ctenophora (comb jellies) Cnidaria Placozoa Subregnum Bilateria  Acoelomorpha  Orthonectida  Rhombozoa  Myxozoa  Superphylum Deuterostomia     Chordata (vertebrates, etc. ... In biology, a species is, loosely speaking, a group of related organisms that share a more or less distinctive form and are capable of interbreeding. ... In biology, a species is, loosely speaking, a group of related organisms that share a more or less distinctive form and are capable of interbreeding. ...

The idea of animal territories was first introduced by the ornithologist Eliot Howard in a book published in 1920. It was widely popularised by Robert Ardrey in his book The Territorial Imperative, and the popularity of this book led to an exaggerated perception of the importance of territory in social ethology. In fact only a minority of species maintain territories with well defined boundaries, within which they live and find all the resources they need. Eliot Howard (November 13, 1873 - December 26, 1940) was an English ornithologist. ... 1920 is a leap year starting on Thursday (link will take you to calendar) // Events January January 7 - Forces of Russian White admiral Kolchak surrender in Krasnoyarsk. ...

The most obvious examples of the "classic" territory are birds and fish, often brightly coloured ones like the European Robin or the Siamese Fighting Fish. Animals like these defend territories that contain their nest site and sufficient food resources for themselves and their young. Defence rarely takes the form on overt fights: more usually there is a highly noticeable display, which may be visual (as in the red breast of the robin), auditory (as in much bird song, or the calls of gibbons) or olfactory, through the deposit of scent marks. Many territorial mammals use scent-marking to signal the boundaries of their territories; the marks may be deposited by urination, by defecation, or by rubbing parts of the bodies that bear specialised scent glands against the substrate. For example, dogs and other canids scent-mark by urination and defecation, while cats scent-mark by rubbing their faces and flanks against objects. Orders Many - see section below. ... Atlantic herring, Clupea harengus, the most abundant fish species in the world. ... Binomial name Erithacus rubecula (Linnaeus, 1758) The European Robin (Erithacus rubecula) is a small passerine bird that was formerly classed as a member of the thrush family, but is now considered to be an Old World flycatcher, Muscicapidae. ... Binomial name Betta splendens Regan, 1910 The Siamese fighting fish (Betta splendens) is one of the most popular species of freshwater aquarium fish. ... Bird song refers to the sounds, usually melodious to the human ear, made by many birds of the order Passeriformes as a form of communication. ... Genera Hylobates Bunopithecus Nomascus Symphalangus Gibbons are small apes that are grouped in the family Hylobatidae. ... Urination, also called micturition, is the process of disposing urine from the urinary bladder through the urethra to the outside of the body. ... Defecation or feceation (known colloquially as pooping, pooing, or shitting, or euphemistically as a bowel movement) is the act of eliminating solid or semisolid waste material from the digestive tract. ... Trinomial name Canis lupus familiaris The Dog is a canine carnivorous mammal that has been domesticated for at least 14,000 years and perhaps for as long as 150,000 years based on recent evidence. ... Genera Alopex Atelocynus Canis Cerdocyon Chrysocyon Cuon Dusicyon Fennecus Lycalopex Lycaon Nyctereutes Otocyon Pseudalopex Speothos Urocyon Vulpes Canidae is the family of carnivorous and omnivorous mammals commonly known as canines. ...

Territories may be held by an individual, a mated pair, or a group. Territoriality is not a fixed property of a species: for example, robins defend territories as pairs during the breeding season and as individuals during the winter, while some nectarivores defend territories only during the mornings (when plants are richest in nectar). In species that do not form pair bonds, male and female territories are often independent, in the sense that males defend territories only against other males, and females only against other females; in this case, if the species is polygynous, one male territory will probably contain several female territories, while in some polyandrous species such as the Northern Jacana, this situation is reversed. The term polygyny (neo-Greek: poly+gyne woman) is used in related ways in social anthropology and sociobiology. ... In social anthropology and sociobiology, polyandry (Greek: poly many, andras man) means a female forming a stable sexual union with more than one male. ... Binomial name Jacana spinosa (Linnaeus, 1758) The Northern Jacana Jacana spinosa is a wader which is a resident breeder from Mexico to western Panama, and on Cuba, Jamaica and Hispaniola. ...

Quite often territories that only yield a single resource are defended. For example, European Blackbirds may defend feeding territories that are distant from their nest sites, and in some species that form leks, for example the Uganda kob (a grazing antelope), males defend the lek site (which is used only for mating). For the reconnaissance aircraft, see SR-71 Blackbird. ... A lek (from Swedish lek, a noun which typically denotes pleasurable and less rule-bound games and activities) is a tournament (the males of certain species of animals for the purposes of competitive mating display), held before and during the breeding season, day after day, when the same group of... Genera Hippotragus Oryx Addax A grazing antelope is any of the 6 species of antelope that make up the subfamily Hippotraginae in the family Bovidae, which also includes sheep, goats, and cattle. ...

Territoriality is only shown by a minority of species. More commonly, an individual or a group of animals will have an area that it habitually uses but does not necessarily defend; this is called its home range. The home ranges of different groups often overlap, and in the overlap areas the groups will tend to avoid each other rather than seeking to expel each other. Within the home range there may be a core area that no other individual group uses, but again this is as a result of avoidance rather than defence.

Behavioural ecologists have argued that food distribution determines whether a species will be territorial or not. Territoriality is only expected to emerge where there is a focused resource that provides enough for the individual or group, within a boundary that is small enough to be defended without the expenditure of too much effort.

Territoriality is least likely with insectivorous birds, where the food supply is plentiful but unpredictably distributed. Swifts rarely defend an area larger than the nest. Genera Many; see text. ...

Conversely, large solitary (or paired) carnivores, such as bears and the bigger raptors require an extensive protected area to guarantee their food supply. this territoriality will only break down when there is a glut of food, for example when Grizzly Bears are attracted to migrating salmon. For other meanings, see Bear (disambiguation). ... Orders Accipitriformes     Cathartidae     Pandionidae     Accipitridae     Sagittariidae Falconiformes     Falconidae A bird of prey or raptor is a bird that hunts its food, especially one that preys on mammals or other birds. ... Binomial name Ursus arctos Linnaeus, 1758 The Brown Bear (Ursus arctos) is a species of bear that can reach weights of 130-700 kg (300 to 1500 pounds). ... The Chinook or King Salmon is the largest salmon in North America and can grow up to 58 long and 126 pounds. ...