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Proc Biol Sci. Oct 22, 1998; 265(1409): 1997–2002.
PMCID: PMC1689481

Larger sperm outcompete smaller sperm in the nematode Caenorhabditis elegans.


Sperm competition is generally thought to drive the evolution of sperm miniaturization. Males gain advantage by transferring more sperm, which they produce by dividing limited resources into ever smaller cells. Here, we describe the opposite effect of size on the competitiveness of amoeboid sperm in the hermaphroditic nematode Caenorhabditis elegans. Larger sperm crawled faster and displaced smaller sperm, taking precedence at fertilization. Larger sperm took longer to produce, however, and so were more costly than smaller sperm. Our results provide evidence of a mechanism to support recent theoretical and comparative studies that suggest sperm competition can favour not small, but large sperm.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.
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Articles from Proceedings of the Royal Society B: Biological Sciences are provided here courtesy of The Royal Society


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