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:
“The first general store opened on the ‘Cold Saturday’ of the winter of 1833 ... Mrs. Mary Miller, daughter of the store’s promoter, recorded in a letter: ‘Chickens and birds fell dead from their roosts, cows ran bellowing through the streets’; but she failed to state what effect the freeze had on the gala occasion of the store opening.”
—Administration in the State of Sout, U.S. public relief program (1935-1943)
“As they are not seen on their way down the streams, it is thought by fishermen that they never return, but waste away and die, clinging to rocks and stumps of trees for an indefinite period; a tragic feature in the scenery of the river bottoms worthy to be remembered with Shakespeare’s description of the sea-floor.”
—Henry David Thoreau (1817–1862)
“Oh! no! we never mention her,
Her name is never heard;
My lips are now forbid to speak
That once familiar word.”
—Thomas Bayly (1797–1839)
“Histories are more full of examples of the fidelity of dogs than of friends.”
—Alexander Pope (1688–1744)