Colonial ants have long been fascinating to scientists and non-professionals alike, and rightly so. After all, here we have thousands of individuals acting essentially as though they were one super organism under the command, so to speak, of a single individual, the queen. As the sole reproductive female in most kinds of colonial ants, the fate of the colony rests largely on the genetics of her and her ephemeral consort.
Now there comes a new twist. It seems that some species of a
Southwestern genus of ants has three sexes instead of the usual two. In most ants, the
queen and the workers share the same genes, with differences among the various castes
within the ant hill being due to differences in nutrition and other environmental
factors. But in these newly investigated species, the queen must mate with males of her
own genetic strain to produce new queens but accept sperm from a male of a different
genetic strain in order to produce workers. Ah for the good old days when a love
triangle meant something entirely different! 
Contributor: Arthur H. Harris, Laboratory for Environmental Biology, Centennial Museum, University of Texas at El Paso.
Desert Diary is a joint production of the Centennial Museum and KTEP National Public Radio at the University of Texas at El Paso.