While researchers assume that wing patterns, body size and color all help male dragonflies recognize females of their own species, the subject has not been well studied, says Dennis Paulson, Director Emeritus of the Slater Museum of Natural History at the University of Puget Sound. Females of some species may closely resemble females of another species, and if the two species occupy the same habitat, males may grab any female they can. Males will even grab other males, Paulson says. In flight, male dragonflies grab females by the head, using special appendages at the end of the abdomen. If the fit isn’t quite right, the female will not cooperate in the aerial mating, and the male will soon let go. In a sense, the female dragonfly is choosing a mate by this act of noncooperation. Females may also “choose” which packets of sperm fertilize their eggs. The degree to which female dragonflies exercise mate choice remains a matter of debate among entomologists, Paulson says.
A female Eight-spotted Skimmer, Libellula forensis Photo © Stephen Hart