Herd

Herd
Boy herding a flock of sheep, India; a classic example of the domestic herding of animals.
Wildebeest at the Ngorongoro Crater; an example of a herd in the wild.

Herd refers to a social grouping of certain animals of the same species, either wild or domestic, and also to the form of collective animal behavior associated with this (referred to as herding) or as a verb, to herd, to its control by another species such as humans or dogs.

The term herd is generally applied to mammals, and most particularly to the grazing ungulates that classically display this behaviour. Different terms are used for similar groupings in other species; in the case of birds, for example, the word is flocking, but flock may also be used, in certain instances, for mammals, particularly sheep or goats. A group of quail is often referred to as a covey. Large groups of carnivores are usually called packs, and in nature a herd is classically subject to predation from pack hunters.

Special collective nouns may be used for particular taxa (for example a flock of geese, if not in flight, is sometimes called a gaggle) but for theoretical discussions of behavioural ecology, the generic term herd can be used for all such kinds of assemblage.[citation needed]

The word herd, as a noun, can also refer to one who controls, possesses and has care for such groups of animals when they are domesticated. Examples of herds in this sense include shepherds (who tend to sheep), goatherds (who tend to goats), cowherds (who tend cattle), and others.

Contents

Why do animals herd?

When an association of animals (or, by extension, people) is described as a "herd", the implication is that the group tends to act together (for example, all moving in the same direction at a given time), but that this does not occur as a result of planning or co-ordination. Rather, each individual is choosing behaviour that corresponds to that of the majority of other members, possibly through imitation or possibly because all are responding to the same external circumstances. A herd can be contrasted with a co-ordinated group where individuals have distinct roles. Many human groupings, such as army detachments or sports teams, show such co-ordination and differentiation of roles, but so do some animal groupings such as those of eusocial insects, which are co-ordinated through pheromones and other forms of animal communication.

Large groupings of birds in flight are generally referred to as a flock

The question of why animals group together is one of the most fundamental in sociobiology and behavioural ecology. As noted above, the term "herd" is most commonly used of grazing animals such as ungulates, and in these cases it is believed that the strongest selective pressure leading to herding rather than a solitary existence is protection against predators. There is clearly a tradeoff involved, since on the one hand a predator may hesitate to attack a large group of animals, while on the other a large group offers an easily detected target. It is generally believed that the most important protective factor is risk dilution - even if a predator attacks the herd, the risk for any individual that it will be the victim is greatly reduced. In the case of predators, it is often unclear whether the term "herd" is appropriate, since there may be some degree of co-ordination or role differentiation in group hunting. Predator groups are commonly smaller than grazing groups, since although a pack may be more effective at pulling down prey than a single animal, the prey then has to be shared between all members, so that the weaker animals will often be better off hunting smaller prey on their own.

The structure and size of herds

A herd is by definition relatively unstructured. However, there may be one or a few animals which tend to be imitated by the rest of the members of the herd more than others. An animal taking this role is called a "control animal", since its behaviour will predict that of the herd as a whole. It cannot be assumed, however, that the control animal is deliberately taking a leadership role. Control animals are not necessarily, or even usually, those that are socially dominant in conflict situations, though they frequently are. Group size is an important characteristic of the social environment of gregarious species.

A Snow Goose gaggle may contain thousands.

Domestic herds

Domestic animal herds are assembled by humans for practicality in raising them and controlling them. Their behaviour may be quite different from that of wild herds of the same or related species, since both their composition (in terms of the distribution of age and sex within the herd) and their history (in terms of when and how the individuals joined the herd) are likely to be very different.

A herd of goats in Greece

Human parallels

The term herd is also applied metaphorically to human beings in social psychology, with the concept of herd behaviour. However both the term and concepts that underlie its use are controversial.

The term has acquired a semi-technical usage in behavioral finance to describe the largest group of market investors or market speculators who tend to 'move with the market,' or 'follow the general market trend.' This is at least a plausible example of genuine herding, though according to some researchers it results from rational decisions through processes such as information cascade and rational expectations. Other researchers, however, ascribe it to non-rational process such as mimicry, fear and greed contagion. "Contrarians" or contrarian investors are those who deliberately choose to invest or speculate counter to the "herd".

See also


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Synonyms:
(of the larger animals) / , , , , (ignobile vulgus), (as beasts),


Look at other dictionaries:

  • Herd — (h[ e]rd), n. [OE. herd, heord, AS. heord; akin to OHG. herta, G. herde, Icel. hj[ o]r[eth], Sw. hjord, Dan. hiord, Goth. ha[ i]rda; cf. Skr. [,c]ardha troop, host.] [1913 Webster] 1. A number of beasts assembled together; as, a herd of horses,… …   The Collaborative International Dictionary of English

  • Herd — Herd, v. i. [imp. & p. p. {Herded}; p. pr. & vb. n. {Herding}.] [See 2d {Herd}.] 1. To unite or associate in a herd; to feed or run together, or in company; as, sheep herd on many hills. [1913 Webster] 2. To associate; to ally one s self with, or …   The Collaborative International Dictionary of English

  • Herd — Herd: Das auf das Westgerm. beschränkte Substantiv mhd. hert, ahd. herd, niederl. haard, engl. hearth gehört mit verwandten Wörtern in anderen idg. Sprachen, vgl. z. B. lat. carbo »‹Holz›kohle« (↑ karbo..., ↑ Karbo...) und – weitergebildet –… …   Das Herkunftswörterbuch

  • herd — herd1 [hʉrd] n. [ME < OE heord, akin to Ger herde < IE base * kerdho , a row, group > Sans s̍árdha, a herd, troop] 1. a number of cattle, sheep, or other animals feeding, living, or being driven together 2. a) any large group suggestive… …   English World dictionary

  • Herd — Herd, v. t. To form or put into a herd. [1913 Webster] …   The Collaborative International Dictionary of English

  • Herd — Herd, n. [OE. hirde, herde, heorde, AS. hirde, hyrde, heorde; akin to G. hirt, hirte, OHG. hirti, Icel. hir?ir, Sw. herde, Dan. hyrde, Goth. ha[ i]rdeis. See 2d {Herd}.] One who herds or assembles domestic animals; a herdsman; much used in… …   The Collaborative International Dictionary of English

  • Herd — [Basiswortschatz (Rating 1 1500)] Auch: • Ofen • Kocher Bsp.: • Du kannst die Suppe auf dem Herd oder in der Mikrowelle aufwärmen. • Profiköche bevorzugen Gasherde. • Wir heizen die Hütte mit einem Holzofen. • …   Deutsch Wörterbuch

  • Herd — (h[ e]rd), a. Haired. [Obs.] Chaucer. [1913 Webster] …   The Collaborative International Dictionary of English

  • Herd — Herd, in der Aufbereitung, s. Herdarbeit; Herd des Schmelzofens, s. Flußeisen, Bd. 4, S. 107 ff., Roheisen, Schweißeisen, Blei, Kupfer, Silber, Oefen, metallurgische …   Lexikon der gesamten Technik

  • herd — [n] large group assemblage, bevy, brood, clan, collection, covey, crowd, crush, drift, drove, flight, flock, gaggle, gathering, hoi polloi*, horde, lot, mass, mob, multitude, nest, pack, people, populace, press, rabble, school, swarm, throng;… …   New thesaurus

  • Herd — Herd, 1) ebener, gewöhnlich erhöhter Platz auf der Erde, gewisse Verrichtungen darauf vorzunehmen; 2) die Erderhöhung beim Vogelherd, wo die Netze liegen; 3) bei Wehren u. bei Schleußen s.u. Wehr u. Schwellwerk; 4) zum Waschen des Erzschliches, s …   Pierer's Universal-Lexikon

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