1979] 
Leston — Dispersal by Male Doryline Ants 
73 
authors propound: the flights of male dorylines have a genetic role, 
one that is doubly important in view of the limited dispersal attri¬ 
butes of the flightless females. 
The conclusion of Haddow et al. (1966), that ‘seasonal fluctua¬ 
tions . . . are probably not much greater than the night-to-night 
variations . . .’ is unsupported and results from the defects in their 
sampling method, noted below. Figs. 3 and 4, to a lesser extent Fig. 
5, demonstrate a marked seasonal periodicity in frequencies. 
The peak emission of males by Dorylini at Legon during the first 
wet sunny season of Gibbs and Leston (1970) is concurrent with the 
production of maximum numbers of alates in the ubiquitous and 
arboreal-nesting formicine Oecophylla longinoda (Latreille) (Leston 
and Gibbs, 1971) and in the similar nesting but strictly forest-zone 
myrmicine Macromischoides aculeatus (Mayr) (Aryeetey, 1971) 
The peak in Anomma approximates that found in the ground¬ 
nesting forest ponerine Odontomachus troglodytes Santschi (Gibbs 
and Leston, 1970); during the second wet sunny season, a season not 
clearly delimited at Legon but distinct in the nearby forest zone 
(Fig. 5). 
In Oecophylla and Macromischoides it appears that the ultimate 
factor is the optimization of conditions for the production of the 
first broods by the solitary queen (Leston, 1972). After the end of 
the first wet sunny season there is a dramatic drop in the available 
prey (Gibbs and Leston, 1970) and a reduction too in mean temper¬ 
ature. However, colonies are not, in Dorylini, founded by a single, 
claustral queen but by budding. It is suggested the ultimate factor in 
the production of sexuals in Dorylini is the availability to the parent 
colony during the beginning of the first wet sunny season, of abun¬ 
dant insects and earthworms, their known prey (Gotwald, 1974) 
The annual peak (Fig. 3) falls within the wet sunny period, April 
through to the end of May (Fig. 1). In the nearby forest zone this 
wet sunny season is longer and there is, too, a second one later in the 
year (Fig. 5). 
The attempt to fit all biological periodicities in the humid tropics 
into an alternation of wet and dry ‘seasons’ still persists. Thus Karr 
(1976): Life history adaptations to seasonal changes in rainfall are 
well documented.’ Karr then lists no fewer than 22 papers in 
support-including Gibbs and Leston (1970), which says just the 
reverse! Kannowski’s (1969) conclusion—‘The interface between the 
wet and dry seasons appears to be the most important time of the 
