Determinants of within‐ and among‐clutch variation in levels of maternal hormones in Black‐Headed Gull eggs

  title={Determinants of within‐ and among‐clutch variation in levels of maternal hormones in Black‐Headed Gull eggs},
  author={Ton G. G. Groothuis and Hubert Schwabl},
  journal={Functional Ecology},
1. Females of egg-laying vertebrates may adjust the development of their offspring to prevailing environmental conditions by regulating the deposition of hormones into their eggs. Within- and amng-clutch variation in levels of steroid hormones were studied in the egg yolks of the Black-Headed Gull (Larus ridibundus, Linnaeus) in relation to environmental conditions at the nest site, This species breeds in colonies of different densities and in different habitats, and the chicks hatch… 
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