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:
“You have lived longer than I have and perhaps may have formed a different judgment on better grounds; but my observations do not enable me to say I think integrity the characteristic of wealth. In general I believe the decisions of the people, in a body, will be more honest and more disinterested than those of wealthy men.”
—Thomas Jefferson (1743–1826)
“The type of fig leaf which each culture employs to cover its social taboos offers a twofold description of its morality. It reveals that certain unacknowledged behavior exists and it suggests the form that such behavior takes.”
—Freda Adler (b. 1934)
“Those feelings of envy are familiar to many of us. We see our children accomplishing things that we’ve always been afraid to try, or we give them opportunities that we never had, and we find ourselves feeling jealousy mixed with our pride, or we feel resentful when they take it all for granted.”
—Ruth Davidson Bell (20th century)
“It is hardly to be believed how spiritual reflections when mixed with a little physics can hold people’s attention and give them a livelier idea of God than do the often ill-applied examples of his wrath.”
—G.C. (Georg Christoph)