Testosterone and Polygyny in Birds

  • Les D. Beletsky
  • David F. Gori
  • Scott Freeman
  • John C. Wingfield
Part of the Current Ornithology book series (CUOR, volume 12)


The evolution, maintenance, and functioning of avian mating systems and breeding strategies are of great interest to ethologist and behavioral cologists. Indeed, critical inquiries into the origins of mating systems provided some of the “cornerstone” of the field of behavioral ecology e.g., Crook, 1964; Verner, 1964; Orians, 1969, 1972). Classically, mating systems were defined with respect to the number of mates obtained by males and females per breeding period (Oring, 1982): monogamous individuals had one mate, polygamous individuals more than one, and promiscous individuals mated indiscriminately or nearly so. Recently, recognition has grown that various strategies and selective pressures result in the monogamy/polygamy/promiscuity division and that breeding strategies are not dicrete entities but form a continuum of relationship between the sees. Accordingly, mating systems are now classified by the abilities of individuals to monopolize resources and mates (Emlen and Oring, 1977; Oring, 1982; Gowaty, 1992). For example, monogamy is seen as the consequence of the inability of members of either sex to monopolize more than a single mate. Males may be polygynous because they can garner more than one mate through the acquisition and defense of sufficient breeding resources(thus the designation “resource-defense polygyny”).


Breeding Season Parental Care Territorial Male Song Sparrow Ficedula Hypoleuca 
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Copyright information

© Springer Science+Business Media New York 1995

Authors and Affiliations

  • Les D. Beletsky
    • 1
  • David F. Gori
    • 1
  • Scott Freeman
    • 1
    • 2
  • John C. Wingfield
    • 1
  1. 1.Department of ZoologyUniversity of WashingtonSeattleUSA
  2. 2.Burke MuseumUniversity of WashingtonSeattleUSA

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