General Description and Familiar Examples
Informally, phyla can be thought of as grouping organisms based on general specialization of body plan, At the most basic level, a phylum can be defined in two ways: as a group of organisms with a certain degree of morphological or developmental similarity (the phenetic definition), or a group of organisms with a certain degree of evolutionary relatedness (the phylogenetic definition). Attempting to define a level of the Linnean hierarchy without referring to (evolutionary) relatedness is an unsatisfactory approach, but the phenetic definition is more useful when addressing questions of a morphological nature—such as how successful different body plans were.
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Famous quotes containing the words general, description, familiar and/or examples:
“Suppose we think while we talk or write—I mean, as we normally do—we shall not in general say that we think quicker than we talk, but the thought seems not to be separate from the expression.”
—Ludwig Wittgenstein (1889–1951)
“It [Egypt] has more wonders in it than any other country in the world and provides more works that defy description than any other place.”
—Herodotus (c. 484–424 B.C.)
“For anyone addicted to reading commonplace books ... finding a good new one is much like enduring a familiar recurrence of malaria, with fever, fits of shaking, strange dreams. Unlike a truly paludismic ordeal, however, the symptoms felt while savoring a collection of one man’s pet quotations are voluptuously enjoyable ...”
—M.F.K. Fisher (1908–1992)
“There are many examples of women that have excelled in learning, and even in war, but this is no reason we should bring ‘em all up to Latin and Greek or else military discipline, instead of needle-work and housewifry.”
—Bernard Mandeville (1670–1733)