Cat Fight? Try Guppy Fight


Guppies and minnows; artwork by Hashime Murayama


Apparently it doesn’t matter what your species is:  the opposite sex causes you nothing but trouble.  The latest evidence of this sad-but-true fact comes from scientists at the University of Exeter who have published a study on female aggression in Trinidadian guppies (Poecilia reticulata).  Researchers observed and compared the behavior of a female-only guppy shoal with the behavior of a female shoal after a male had been introduced.   They discovered that female guppies were more likely to turn on one another if a male was present.

Why?  Male Trinidadian guppies often harass females in order to mate with them.  Scientists believe that the time and effort spent resisting a male’s amorous advances may mean that female guppies have less time to spend getting to know one another and may interfere with their ability to form the social hierarchies that enable peaceful group interactions.

The study was published earlier this month in Biology Letters.

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Alyson Foster works in the National Geographic Library where she purchases books for the Library’s collection and assists NG staff with finding research materials.