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In studies of social animals, the highest ranking individual is sometimes designated as the alpha. Males, females, or both, can be alphas, depending on the species. Where one male and one female fulfill this role together, they are sometimes referred to as the alpha pair. Other animals in the same social group may exhibit deference or other species-specific subordinate behaviours towards the alpha or alphas. Alpha animals usually gain preferential access to food and other desirable items or activities, though the extent of this varies widely between species. Male or female alphas may gain preferential access to sex or mates; in some species, only alphas or an alpha pair reproduce. Alphas may achieve their status by superior physical strength and aggression, or through social efforts and building alliances within the group. The individual with alpha status sometimes changes, often through a fight between the dominant and a subordinate animal. Such fights may or may not be to the death. ==Beta and Gamma== Social animals in a hierarchic community are sometimes assigned ranks in ethology studies. Beta animals often act as second-in-command to the reigning alpha or alphas and will act as new alpha animals if an alpha dies or is otherwise no longer considered an alpha. In some species of birds, males pair up in twos when courting, the beta male aiding the alpha male. In wolves, the beta male is not generally allowed to mate with the females, but if the old alpha is removed or dies, he takes over the alpha's females, becoming the new alpha. It has been found that the social context of the animals has a significant impact on courtship behavior and the overall reproductive success of that animal. Gammas (usually rendered ) is an antonym used to refer to the lowest caste of the hierarchical society. Gamma animals are subordinate to all others in the community, and are expected by others in the group to remain submissive to everyone. Gamma animals may also be used as communal scapegoats or outlets for frustration, or given the lowest priority when distributing food.〔Jim Dutcher, Jamie Dutcher, James Manfull (''Wolves at our door: the extraordinary story of the couple who lived with wolves'' ) pp.89, 145〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Alpha (ethology)」の詳細全文を読む スポンサード リンク
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