Although related, Cataglyphis floricola and C. tartessica show very different responses to colony orphaning. In the laboratory, under queenless conditions, C. tartessica workers produced male offspring via arrhenotoky, while C. floricola workers produced female offspring, including new queens, via thelytoky. In the field, C. floricola colonies were more likely than C. tartessica colonies to be orphaned in the late spring. Worker thelytoky could have evolved in C. floricola as an adaptive response to the species’...