Swallow tail streamer is a mechanical device for self-deflection of tail leading edge, enhancing aerodynamic efficiency and flight manoeuvrability

  title={Swallow tail streamer is a mechanical device for self-deflection of tail leading edge, enhancing aerodynamic efficiency and flight manoeuvrability},
  author={R. {\AA}ke Norberg},
  journal={Proceedings of the Royal Society of London. Series B: Biological Sciences},
  pages={227 - 233}
  • R. Norberg
  • Published 22 September 1994
  • Biology
  • Proceedings of the Royal Society of London. Series B: Biological Sciences
In some birds, sexual selection, owing to female preference for long tails in mate choice, has led to tails large enough to constitute serious handicaps in flight, incurring a cost in terms of natural selection. Elongated tails also occur among species that depend heavily on flight for foraging, but then usually only the outer tail feathers are long, often being drawn out into narrow streamers. Apart from their role in mate choice, no functional explanation has ever been given of these tail… 

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