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Sexual selection. Are ducks impressed by drakes' display?
K G McCracken1, R E Wilson, P J McCracken
1Institute of Arctic Biology and Department of Biology and Wildlife, University of Alaska Fairbanks, Fairbanks, Alaska 99775, USA. fnkgm@uaf.edu
Nature
|September 15, 2001
Summary
The Argentine lake duck possesses the longest bird penis, measuring nearly half a meter and featuring a corkscrew shape. Evolutionary factors may involve sexual selection and female preference for longer or decorated penises.
Area of Science:
- Evolutionary Biology
- Zoology
- Comparative Anatomy
Background:
- Few avian species exhibit phallus development.
- The Argentine lake duck (Oxyura vittata) is a notable exception with a highly developed penis.
Purpose of the Study:
- To document and describe the extraordinary penis morphology of the Argentine lake duck.
- To explore potential evolutionary drivers behind the development of this unique avian sexual organ.
Main Methods:
- Morphological analysis of the Argentine lake duck's penis.
- Comparative review of penis evolution in avian species.
Main Results:
- The Argentine lake duck's penis is corkscrew-shaped and measures approximately half a meter, representing the largest known penis among birds.
- Potential evolutionary pressures include sexual selection and female mate choice.
Conclusions:
- The extreme penis morphology in the Argentine lake duck is likely shaped by intense sexual selection.
- Further research is warranted to fully elucidate the complex evolutionary dynamics driving penis elaboration in this species.
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