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Biology

Selected Works

Troy G Murphy

Sexual selection

Articles 1 - 5 of 5

Full-Text Articles in Life Sciences

Migration And The Evolution Of Sexual Dichromatism: Evolutionary Loss Of Female Coloration With Migration Among Wood-Warblers, Richard Simpson, Michele Johnson, Troy Murphy Jul 2015

Migration And The Evolution Of Sexual Dichromatism: Evolutionary Loss Of Female Coloration With Migration Among Wood-Warblers, Richard Simpson, Michele Johnson, Troy Murphy

Troy G Murphy

The mechanisms underlying evolutionary changes in sexual dimorphism have long been of interest to biologists. A striking gradient in sexual dichromatism exists among songbirds in North America, including the wood-warblers (Parulidae): males are generally more colourful than females at northern latitudes, while the sexes are similarly ornamented at lower latitudes. We use phylogenetically controlled comparative analysis to test three nonmutually exclusive hypotheses for the evolution of sexual dichromatism among wood-warblers. The first two hypotheses focus on the loss of female coloration with the evolution of migration, either owing to the costs imposed by visual predators during migration, or owing to …


Sex-Role Reversal In Song? Females Sing More Frequently Than Males In The Streak-Backed Oriole, J. J. Price, L. Yunes-Jimenez, M. Osorio-Beristain, K. E. Omland, Troy G. Murphy Apr 2015

Sex-Role Reversal In Song? Females Sing More Frequently Than Males In The Streak-Backed Oriole, J. J. Price, L. Yunes-Jimenez, M. Osorio-Beristain, K. E. Omland, Troy G. Murphy

Troy G Murphy

Birds in which both sexes produce complex song are more common in the tropics than in the temperate north, where typically only males sing. Yet surprisingly little is known about female song characteristics in most tropical species. Here we present a comparison of female and male singing behaviors in the Streak-backed Oriole (Icterus pustulatus), a tropical songbird in which both sexes perform solo songs. Females sing much more frequently than males and produce songs with similar acoustic complexity. Rates of singing by both sexes were higher during breeding than postbreeding while the rates of most other vocalizations did …


Lack Of Assortative Mating For Tail, Body Size, Or Condition In The Elaborate Monomorphic Turquoise-Browed Motmot (Eumomota Superciliosa), Troy G. Murphy Apr 2015

Lack Of Assortative Mating For Tail, Body Size, Or Condition In The Elaborate Monomorphic Turquoise-Browed Motmot (Eumomota Superciliosa), Troy G. Murphy

Troy G Murphy

Elaborate male and female plumage can be maintained by mutual sexual selection and function as a mate-choice or status signal in both sexes. Both male and female Turquoise-browed Motmot (Eumomota superciliosa) have long tails that terminate in widened blue-and-black rackets that appear to hang, unattached, below the body of the bird. I tested whether mutual sexual selection maintains the Turquoise-browedMotmot’s elaborate tail plumage by testing the prediction that mating occurs in an assortative manner for tail plumage. I also tested whether assortative mating occurs for body size, a potential measure of dominance, and for phenotypic condition, a measure of individual …


Lack Of Assortative Mating For Tail, Body Size, Or Condition In The Elaborate Monomorphic Turquoise-Browed Motmot (Eumomota Superciliosa), Troy G. Murphy Apr 2015

Lack Of Assortative Mating For Tail, Body Size, Or Condition In The Elaborate Monomorphic Turquoise-Browed Motmot (Eumomota Superciliosa), Troy G. Murphy

Troy G Murphy

Elaborate male and female plumage can be maintained by mutual sexual selection and function as a mate-choice or status signal in both sexes. Both male and female Turquoise-browed Motmot (Eumomota superciliosa) have long tails that terminate in widened blue-and-black rackets that appear to hang, unattached, below the body of the bird. I tested whether mutual sexual selection maintains the Turquoise-browedMotmot’s elaborate tail plumage by testing the prediction that mating occurs in an assortative manner for tail plumage. I also tested whether assortative mating occurs for body size, a potential measure of dominance, and for phenotypic condition, a measure of individual …


Racketed Tail Of The Male And Female Turquoise-Browed Motmot: Male But Not Female Tail Length Correlates With Pairing Success, Performance, And Reproductive Success, Troy Murphy Apr 2015

Racketed Tail Of The Male And Female Turquoise-Browed Motmot: Male But Not Female Tail Length Correlates With Pairing Success, Performance, And Reproductive Success, Troy Murphy

Troy G Murphy

Both males and females of many avian species maintain elaborate plumage traits, and elaborate monomorphic plumage may convey adaptive benefits to one or both sexes as inter- or intraspecific signals. Both sexes of the turquoise-browed motmot (Eumomota superciliosa) are elaborately plumed with long racket-tipped tail. I investigated whether the racketed tail functions as a sexually selected signal in one or both sexes by testing the predictions that males and/or females with the largest tails have: (1) greater pairing success, (2) greater reproductive performance (clutch-initiation date, clutch size, and hatching success), and (3) greater reproductive success. Yearling males with longer denuded …