caa a22 4500 463175662 CHVBK 20180406164825.0 cr unu---uuuuu 170326e20071201xx s 000 0 eng 10.1007/s10336-007-0235-0 doi (NATIONALLICENCE)springer-10.1007/s10336-007-0235-0 Endocrine responsiveness to social challenges in northern and southern hemisphere populations of Zonotrichia [Elektronische Daten] [John Wingfield, Simone Meddle, Ignacio Moore, Shallin Busch, Douglas Wacker, Sharon Lynn, Aaron Clark, Rodrigo Vasquez, Elizabeth Addis] Northern populations of the White-crowned Sparrow, Zonotrichia leucophrys, show varying degrees of social modulation of testosterone. In general, males of mid-latitude breeding and multiple-brooded populations show transient increases in secretions of luteinizing hormone and testosterone when challenged by another male for a territory, or when exposed to sexually receptive females. These surges of testosterone do not appear to activate aggression associated with territory defense or mate-guarding, but appear to enhance persistence of aggression during and after the behavioral interaction. Males may continue to sing spontaneously and patrol the territory for many hours even after the behavioral interaction is over. However, males of high latitude and altitude populations do not socially modulate testosterone levels. Several hypotheses, not necessarily mutually exclusive, have been proposed to explain why males in some populations do socially modulate testosterone and others do not. Males will not socially modulate testosterone if: (1) the breeding season is so restricted in time (e.g., high latitude and altitude) there are few social interactions; (2) populations in which males are essential for parental care; and (3) populations in which extra-pair copulations are low and male-male interactions are minimal. Tropical populations of the Rufous-collared Sparrow, Z. capensis costaricensis, have extended breeding seasons and they are multiple-brooded, but do not socially modulate testosterone. This is unlike Z. leucophrys. Whether austral populations of the Rufous-collared Sparrow socially modulate testosterone under presumably similar constraints of mid- to high-latitude seasonality are currently under investigation. Dt. Ornithologen-Gesellschaft e.V., 2007 Aggression nationallicence Agonistic behavior nationallicence Mate guarding nationallicence Social modulation nationallicence Testosterone nationallicence Wingfield John Department of Biology, University of Washington, Box 351800, 98195, Seattle, WA, USA aut Meddle Simone Centre for Integrative Physiology, School of Medicine and Veterinary Medicine, University of Edinburgh, George Square, Edinburgh, UK aut Moore Ignacio Department of Biological Sciences, Virginia Tech, 2119 Derring Hall, 24061, Blacksburg, VA, USA aut Busch Shallin Department of Biology, University of Washington, Box 351800, 98195, Seattle, WA, USA aut Wacker Douglas Department of Biology, University of Washington, Box 351800, 98195, Seattle, WA, USA aut Lynn Sharon Department of Biology, The College of Wooster, 931 College Mall, 44691, Wooster, OH, USA aut Clark Aaron Department of Biology, University of Washington, Box 351800, 98195, Seattle, WA, USA aut Vasquez Rodrigo Institute of Ecology and Biodiversity, Departamento de Ciencias Ecologicas, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago, Chile aut Addis Elizabeth Department of Biology, University of Washington, Box 351800, 98195, Seattle, WA, USA aut Journal of Ornithology Springer-Verlag 148(2007-12-01), 435-441 0021-8375 148<435 2007 148 10336 https://doi.org/10.1007/s10336-007-0235-0 text/html Onlinezugriff via DOI 1 review-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10336-007-0235-0 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Wingfield John Department of Biology, University of Washington, Box 351800, 98195, Seattle, WA, USA aut NATIONALLICENCE 700 1- Meddle Simone Centre for Integrative Physiology, School of Medicine and Veterinary Medicine, University of Edinburgh, George Square, Edinburgh, UK aut NATIONALLICENCE 700 1- Moore Ignacio Department of Biological Sciences, Virginia Tech, 2119 Derring Hall, 24061, Blacksburg, VA, USA aut NATIONALLICENCE 700 1- Busch Shallin Department of Biology, University of Washington, Box 351800, 98195, Seattle, WA, USA aut NATIONALLICENCE 700 1- Wacker Douglas Department of Biology, University of Washington, Box 351800, 98195, Seattle, WA, USA aut NATIONALLICENCE 700 1- Lynn Sharon Department of Biology, The College of Wooster, 931 College Mall, 44691, Wooster, OH, USA aut NATIONALLICENCE 700 1- Clark Aaron Department of Biology, University of Washington, Box 351800, 98195, Seattle, WA, USA aut NATIONALLICENCE 700 1- Vasquez Rodrigo Institute of Ecology and Biodiversity, Departamento de Ciencias Ecologicas, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago, Chile aut NATIONALLICENCE 700 1- Addis Elizabeth Department of Biology, University of Washington, Box 351800, 98195, Seattle, WA, USA aut NATIONALLICENCE 773 0- Journal of Ornithology Springer-Verlag 148(2007-12-01), 435-441 0021-8375 148<435 2007 148 10336 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer