Phenotypic flexibility in basal metabolic rate and the changing view of avian physiological diversity: a review

  title={Phenotypic flexibility in basal metabolic rate and the changing view of avian physiological diversity: a review},
  author={Andrew E. McKechnie},
  journal={Journal of Comparative Physiology B},
  • A. McKechnie
  • Published 1 March 2008
  • Biology, Environmental Science
  • Journal of Comparative Physiology B
Comparative analyses of avian energetics often involve the implicit assumption that basal metabolic rate (BMR) is a fixed, taxon-specific trait. However, in most species that have been investigated, BMR exhibits phenotypic flexibility and can be reversibly adjusted over short time scales. Many non-migrants adjust BMR seasonally, with the winter BMR usually higher than the summer BMR. The data that are currently available do not, however, support the idea that the magnitude and direction of… 
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