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.
Read more about this topic: Phylum
Famous quotes containing the words general, description, familiar and/or examples:
“An aristocratic culture does not advertise its emotions. In its forms of expression it is sober and reserved. Its general attitude is stoic.”
—Johan Huizinga (1872–1945)
“The great object in life is Sensation—to feel that we exist, even though in pain; it is this “craving void” which drives us to gaming, to battle, to travel, to intemperate but keenly felt pursuits of every description whose principal attraction is the agitation inseparable from their accomplishment.”
—George Gordon Noel Byron (1788–1824)
“All the familiar horrors we
Associate with others
Are coming fast along our way:
The wind is warning in our tree
And morning papers still betray
The shrieking of the mothers.”
—Philip Larkin (1922–1986)
“Histories are more full of examples of the fidelity of dogs than of friends.”
—Alexander Pope (1688–1744)