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DIVERGENCE IN MONARDA (LABIATAE)
Author(s) -
Scora Rainer W.
Publication year - 1967
Publication title -
taxon
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.819
H-Index - 81
eISSN - 1996-8175
pISSN - 0040-0262
DOI - 10.2307/1216953
Subject(s) - taxon , divergence (linguistics) , genus , character (mathematics) , biology , phylogenetic tree , botany , evolutionary biology , mathematics , genetics , philosophy , gene , linguistics , geometry
Summary A phylogenetic evaluation of the genus Monarda is presented, based upon biological divergence including anatomical, chemical, cytological and morphological characters. The evaluation is patterned after the “Wagner Divergence Index” which is based on two main assumptions: first, since there is no logically tenable way of measuring objectively the value of various characters, they are treated as of equal value; second, any character that occurs in most taxa of a given group is probably the norm and therefore unspecialized; a character appearing only in a few of the taxa of a group is considered to be specialized. Of 118 classical taxonomic characters found in the genus Monarda, only 31 were considered to have recognizable evolutionary tendencies, and of 26 chemical oil constituents only 9 were judged to have evolutionary significance.