Dispersal polymorphism and physiological condition of males and females in the ant, Formica truncorum

This study deals with dispersal behavior of sexuals and intraspecificvariation in queen numbers. The specific questions are: (1)Is there an association between male and female dispersal behaviorand the number of queens in a colony? (2) Is there an associationbetween individual behavior and physiological condition? (3)Do males and females from monogyne (one queen per colony) andpolygyne (several functional queens per colony) colonies differwith respect to size, weight, and physiological condition? Theresults show that both males and females are more prone to dispersein monogyne than in polygyne colonies. Moreover, males and femalesof both monogyne and polygyne colonies show dispersal polymorphism,suggesting that an increased tendency of reproductive femalesto stay in the maternal colony may cause monogyne colonies toswitch to polygyny. The propensity to disperse is associatedwith the physiological condition of individuals. Larger andheavier females containing more fat and glycogen preferentiallydisperse, whereas smaller ones with less fat and glycogen moreeasily dealate and mate without a previous nuptial flight. Maledispersal correlates positively to larger size and higher levelsof glycogen; fat contents do not increase during maturation.The females produced in monogyne colonies are larger, heavier,and contain more fat and glycogen than those produced in polygynecolonies. The males produced in monogyne colonies have relativelylonger wings and are heavier than those produced in polygynecolonies. However, there are no differences in size and fatcontents between males from monogyne and polygyne colonies.