Nuptial food gifts given by males to females at mating are widespread in in
sects, but their evolutionary origin remains obscure. Such gifts may arise
as a form of sensory trap that exploits the normal gustatory responses of f
emales, favouring the selective retention of sperm of gift-giving males. I
tested this hypothesis by offering foreign food gifts, synthesized by males
of one cricket species, to females of three non-gift-giving species. Femal
es provisioned with novel food gifts were 'fooled' into accepting more sper
m than they otherwise would in the absence of a gift. These results support
the hypothesis that nuptial food gifts and post-copulatory female mating p
references coevolve through a unique form of sensory exploitation.