A Supplemental Function of the Avian Egg Tooth

  title={A Supplemental Function of the Avian Egg Tooth},
  author={Karen L. Wiebe},
  • K. Wiebe
  • Published 16 March 2010
  • Environmental Science, Biology
Abstract. Hatchlings use egg teeth to help break through the shell during hatching, but these structures could have an additional function of increasing nestlings' visibility. I investigated the size, color, and persistence of egg teeth in woodpeckers, which nest in dark cavities. Many species of woodpecker have two egg teeth, one each on the tip of the maxilla and of the mandible, which, together with the pale flanges, frame the open mouth when nestlings gape. A spectrometer confirmed that… 

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