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Parental Care and Clutch Sizes in North and South American Birds
Nebraska Cooperative Fish & Wildlife Research Unit -- Staff Publications
  • Thomas E. Martin, U.S. Geological Survey
  • P. R. Martin, University of Montana - Missoula
  • C. R. Olson, University of Montana - Missoula
  • B. J. Heidinger, University of Montana - Missoula
  • J. J. Fontaine, University of Montana - Missoula
Date of this Version
Published in Vol 287 (2000)
The evolutionary causes of small clutch sizes in tropical and Southern Hemisphere regions are poorly understood. Alexander Skutch proposed 50 years ago that higher nest predation in the south constrains the rate at which parent birds can deliver food to young and thereby constrains clutch size by limiting the number of young that parents can feed. This hypothesis for explaining differences in clutch size and parental behaviors between latitudes has remained untested. Here, a detailed study of bird species in Arizona and Argentina shows that Skutch's hypothesis explains clutch size variation within North and South America. However, neither Skutch's hypothesis nor two major alternatives explain differences between latitudes.
Citation Information
Thomas E. Martin, P. R. Martin, C. R. Olson, B. J. Heidinger, et al.. "Parental Care and Clutch Sizes in North and South American Birds" (2000)
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