Premium
The evolution of unisexual flowers: morphological and functional convergence results from diverse developmental transitions
Author(s) -
Mitchell Caroline H.,
Diggle Pamela K.
Publication year - 2005
Publication title -
american journal of botany
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.218
H-Index - 151
eISSN - 1537-2197
pISSN - 0002-9122
DOI - 10.3732/ajb.92.7.1068
Subject(s) - biology , phylogenetic tree , evolutionary biology , morphology (biology) , context (archaeology) , type (biology) , dioecy , phylogenetics , evolutionary developmental biology , botany , coevolution , convergent evolution , sexual dimorphism , ontogeny , zoology , ecology , gene , genetics , paleontology , pollen
Unisexual flower morphology was examined within a phylogenetic context in order to identify developmental transitions associated with the multiple origins of dioecy in flowering plants. Historically, two categories of unisexual flowers have been recognized: type I flowers exhibit rudiments of the nonfunctional organ type, while type II flowers bear no vestigial sexual organs. Mapping of these flower types onto a composite phylogeny shows that type II morphology is homoplasious and has resulted from at least four distinct evolutionary developmental pathways. The historical assignment of unisexual flowers into only two morphological types has masked important developmental and evolutionary dynamics.