Species
In biology, a species (plural: species) is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, the difficulty of defining species is known as the species problem. Differing measures are often used, such as similarity of DNA, morphology, or ecological niche. Presence of specific locally adapted traits may further subdivide species into "infraspecific taxa" such as subspecies (and in botany other taxa are used, such as varieties, subvarieties, and formae).
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Famous quotes containing the word species:
“Our species successfully raised children for tens of thousands of years before the first person wrote down the word “psychology.” The fundamental skills needed to be a parent are within us. All we’re really doing is fine-tuning a process that’s already remarkably successful.”
—Lawrence Kutner (20th century)
“There are acacias, a graceful species amusingly devitalized by sentimentality, this kind drooping its leaves with the grace of a young widow bowed in controllable grief, this one obscuring them with a smooth silver as of placid tears. They please, like the minor French novelists of the eighteenth century, by suggesting a universe in which nothing cuts deep.”
—Rebecca West (1892–1983)
“Under the species of Syndicalism and Fascism there appears for the first time in Europe a type of man who does not want to give reasons or to be right, but simply shows himself resolved to impose his opinions.”
—José Ortega Y Gasset (1883–1955)