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).
Read more about Species.
Famous quotes containing the word species:
“Nature seemed to have adorned herself for our departure with a profusion of fringes and curls, mingled with the bright tints of flowers, reflected in the water. But we missed the white water-lily, which is the queen of river flowers, its reign being over for this season.... Many of this species inhabit our Concord water.”
—Henry David Thoreau (1817–1862)
“Thus all probable reasoning is nothing but a species of sensation. ‘Tis not solely in poetry and music, we must follow our taste and sentiment, but likewise in philosophy, When I am convinc’d of any principle, ‘tis only an idea which strikes more strongly upon me. When I give the preference to one set of arguments above another, I do nothing but decide from my feeling concerning the superiority of their influence.”
—David Hume (1711–1776)
“Prohibition will work great injury to the cause of temperance. It is a species of intemperance within itself, for it goes beyond the bounds of reason in that it attempts to control a man’s appetite by legislation, and makes a crime out of things that are not crimes. A Prohibition law strikes a blow at the very principles upon which our government was founded.”
—Abraham Lincoln (1809–1865)