Interspecific Variation in Photo-Induced GnRH Plasticity among Nomadic Cardueline Finches

  title={Interspecific Variation in Photo-Induced GnRH Plasticity among Nomadic Cardueline Finches},
  author={Maria Elena Pereyra and Susan M. Sharbaugh and Thomas P. Hahn},
  journal={Brain, Behavior and Evolution},
  pages={35 - 49}
Changes in response to photoperiod are of fundamental importance to seasonal cycles in avian reproductive development. In this study we present data on photo-induced changes in gonadotropin-releasing hormone (GnRH) immunoreactivity associated with the development of photorefractoriness in males of 3 closely related species of cardueline finch: common redpoll (Carduelis flammea), pine siskin (C. pinus) and white-winged crossbill (Loxia leucoptera). All are nomadic, mid- to high-latitude breeders… 

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