Chemical sense

A general term for taste and smell, which are stimulated by chemical substances. Taste is a sensation that occurs when we come into contact with chemical substances in a liquid or water-soluble state, so it is also called contact chemosensation. In contrast, smell is a sensation that occurs when we receive chemical substances in a gaseous state, so it is also called remote chemosensation. In aquatic animals such as fish and amphibians, it is not possible to distinguish between taste and smell based on the state of the chemical substances received, but in terrestrial vertebrates, the sensation caused by stimulation of receptors in the mouth is called taste, and the sensation caused by stimulation of receptors on the surface of the olfactory epithelium is called smell. Chemical senses are universally recognized in animals, and provide important clues for the expression of feeding behavior, sexual behavior, and behavior to escape from predators.

[Tsuneo Yamaguchi]

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

化学物質が刺激になって生ずる味覚と嗅覚(きゅうかく)の総称。味覚は液体または水溶状態にある化学物質に接触したときに生ずる感覚なので、接触化学感覚ともよばれる。これに対して、嗅覚は気体の状態の化学物質を受容したときに生ずる感覚なので、遠隔化学感覚ともよばれる。魚類や両生類のような水生動物では、受容される化学物質の状態から味覚と嗅覚を区別することはできないが、陸生脊椎(せきつい)動物に対応して存在する口内の受容器への刺激による感覚を味覚、嗅上皮表面の受容器への刺激による感覚を嗅覚とよんでいる。化学感覚は動物に普遍的に認められ、求餌(きゅうじ)行動、性行動、害敵からの逃避行動などを発現する重要な手掛りを与える。

［山口恒夫］

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