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发帖数: 3461 | 1 这里是一篇NATURE文章的全文,很有意思. 嘿嘿
有WEB ACCESS的同学可以去看图, Nature, vol 413, 13 sept 2001, page 128
Surprisingly few birds have penises, but among
those that do, the Argentine lake duck(Oxyura vittata) tops
the bill --- the penis of this small stifftail duck from
South America is shaped like a corkscrew and, at almost
half a metre long, is the largest of any bird measured so far.
Factors responsible for the evolution of this remarkable
organ could include runaway selection, whereby drakes
with longer penis |
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