Why Some Birds Take so Long to Hatch

  title={Why Some Birds Take so Long to Hatch},
  author={P. Dee Boersma},
  journal={The American Naturalist},
  pages={733 - 750}
  • P. Boersma
  • Published 1 December 1982
  • Biology, Environmental Science
  • The American Naturalist
In general, incubation periods of bird eggs are positively correlated with egg weights. The eggs of some birds take much longer to hatch than expected. Highly variable and long incubation periods are explained using fork-tailed storm petrels as an example. Their eggs take two to three times as long to hatch as eggs of similar size. Egg neglect causes the extreme variability in incubation periods within a species. Low incubation temperatures prolong incubation, but long incubation periods may… 

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