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:
“Every writer is necessarily a critic—that is, each sentence is a skeleton accompanied by enormous activity of rejection; and each selection is governed by general principles concerning truth, force, beauty, and so on.... The critic that is in every fabulist is like the iceberg—nine-tenths of him is under water.”
—Thornton Wilder (1897–1975)
“The next Augustan age will dawn on the other side of the Atlantic. There will, perhaps, be a Thucydides at Boston, a Xenophon at New York, and, in time, a Virgil at Mexico, and a Newton at Peru. At last, some curious traveller from Lima will visit England and give a description of the ruins of St Paul’s, like the editions of Balbec and Palmyra.”
—Horace Walpole (1717–1797)
“Yes, it is the hour at which, long ago, I felt happy. What always awaited me then was a light and dreamless sleep. But something had changed because, with the wait for tomorrow, it is my cell that I have found. As if the familiar paths traced in the summer skies could lead to prisons as well as innocent slumbers.”
—Albert Camus (1913–1960)
“Histories are more full of examples of the fidelity of dogs than of friends.”
—Alexander Pope (1688–1744)