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:
“What use Milton, a silly story
Of our lost general parents,
eaters of fruit?”
—Gary Snyder (b. 1930)
“It is possible—indeed possible even according to the old conception of logic—to give in advance a description of all ‘true’ logical propositions. Hence there can never be surprises in logic.”
—Ludwig Wittgenstein (1889–1951)
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—Sir James George Frazer (1854–1941)
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—Michel de Montaigne (1533–1592)