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Female woodmice may seek grooming in exchange for sex

source: New Scientist December 4 1999 p23

Researchers from University of Oxford, England, have found that male woodmice tend to occupy themselves grooming females for longer than females groom males (Ethology, vol 105, p982). The researchers, David Macdonald and Pavel Stopka, believe that females seek grooming in exchange for sex. Males may only be able to offer grooming as a resource, due to the promiscuity of wood mice.