Evolutionary systematics

Evolutionary systematics - someone else ought to be able to...

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Evolutionary systematics uses homologous characters but will commonly weight characters differently depending on the "importance" of the character. A good evolutionary systematist is one who "knows" the group and can thus decide which characters to weight more heavily. Criticized as being highly subjective and not scientific because decisions are not testable hypotheses, but statements of faith about the importance of the characters. Acknowledges grade as relevant to the study: crocodiles and birds are different classes to evolutionary systematists, but sister taxa to cladists. Which approach do we use? Ideally a classification should be objective in that the criteria use to classify are not subject to the whim of the person doing the classifying. Objectivity is important if classification is to be a scientific endeavor:
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Unformatted text preview: someone else ought to be able to step in and repeat your "experiment" in classification. Moreover a classification should be natural and not artificial so that if a set of characters were used to assign relationships, these relationships should also be apparent in other characters not used in the analysis. There are natural groups that have been generated during the history of life and systematists should attempt to discover these groups. In recent years cladistics has become the dominant school of systematics as it meets these two criteria well. However, phenetics is still very active and character weighting is still being used. Note that natural groups might generate many more hierarchical levels than the classical Linnaean hierarchy (see fig. 14.8, 14.9, pg. 386-387)....
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This note was uploaded on 11/06/2011 for the course BIO BSC1010 taught by Professor Gwenhauner during the Fall '10 term at Broward College.

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