Table of Contents
ISRN Zoology
Volume 2011, Article ID 251925, 10 pages
Research Article

Phylogenetic Evidence for the Gain and Loss of a Sexually Selected Trait in Sailfin Mollies

Department of Biological Sciences, Clemson University, 132 Long Hall, Clemson, SC 29634-0314, USA

Received 26 January 2011; Accepted 26 February 2011

Academic Editors: D. Russo, P. Scaps, and L. Vicente

Copyright © 2011 Margaret B. Ptacek et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


A phylogenetic comparative approach was used to examine the evolution of the enlarged “sailfin,” characteristic of the monophyletic lineage of sailfin mollies (Poecilia: Mollienesia), but absent in one of its species, P. latipunctata. Ancestral character state reconstructions demonstrated that the ancestral sailfin molly possessed the enlarged sailfin, and, thus, males of P. latipunctata have secondarily lost this trait. The strength of female mating preference was measured in P. latipunctata for two known targets of sexual selection, large male size, and sailfin male phenotype. Females of P. latipunctata preferred conspecific males of larger body size to those of smaller body size, but showed no preference for sailfin males of a related species, P. velifera, when compared with males of the shortfin species, P. mexicana. Taken together, these results suggest that the targets of sexual selection may have shifted in this species and that reduction in female preference for sailfin males may have played a role in the loss of this ornament.