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In biology, a colony refers to individual organisms of the same species living closely together, usually for mutual benefit, such as stronger defense or the ability to attack bigger prey. Some insects (ants and honey bees, for example) live only in colonies. A colonial organism is an organism composed of multiple constituent organisms. The organisms can be unicellular, as in the alga ''Volvox'' (a coenobium), or multicellular, as in the Portuguese man o' war. The former type may have been the first step toward multicellular organisms. A colonial organism can be distinguished from a conventional colony of independent organisms by the closer association of its component parts into discrete individual superorganisms, and typically by the presence of differentiation into two or more specialized component types. Conversely, a colonial organism can be distinguished from a conventional multicellular organism by the looser association and repeating nature of its component subunits—perhaps with specializations, but still visibly similar. The components can also be recognized as organisms in their own right by comparison with evolutionarily related free-living species. For example, the Portuguese man o' war is a colony of four different types of polyp or related forms. These four types can be readily seen to be analogs of one another (or of immature stages), and also of related free-living cnidarians such as jellyfish. A microbial colony is defined as a visible cluster of microorganisms growing on the surface of or within a solid medium, presumably cultured from a single cell. Because the colony is clonal, with all organisms in it descending from a single ancestor (assuming no contamination), they are genetically identical, except for any mutations (which occur at low frequencies). Obtaining such genetically identical organisms (or pure strains) can be useful; this is done by spreading organisms on a culture plate and starting a new stock from a single resulting colony. A biofilm is a colony of microorganisms often comprising several species, with properties and capabilities greater than the aggregate of capabilities of the individual organisms. ==See also== * Ant colony * Beehive (beekeeping) * Bird colony * Clonal colony * Colonisation (biology) * Coral reef * Eusociality * Superorganism * Swarm * Birth colony * ''Austroplatypus incompertus'' 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「Colony (biology)」の詳細全文を読む スポンサード リンク
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