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[Vol. 92 
become secondarily polygynous by accepting young queens into their 
nests (Alloway et al. 1982; for a review of polygyny in ants see 
Holldobler and Wilson 1977). The large proportion of queenless 
nests led Sturtevant (1927) and Talbot (1957) to suggest that colo- 
nies may occupy multiple nests (polydomy); and Sturtevant (1927) 
provided some experimental evidence for this hypothesis by noting 
that nests found relatively close together in nature were occasionally 
non-aggressive toward one another. Similar evidence indicates that 
colonies of L. ambiguus, L. longispinosus and H. americanus can be 
polydomous as well (Alloway et al. 1982; Del Rio Pesado and Allo- 
way 1983). 
The discovery of polygyny and polydomy in this group of ants 
raises numerous questions concerning the structure of colonies and 
locai populations. Colonies possessing these characteristics may be 
capable of existing indefinitely, and of spreading out and occupying 
large areas of suitable habitat. Such “super colonies” are highly 
developed in other groups of ants with these characteristics (e.g. 
Formica yessensis Forel, Higashi and Yamuchi 1979). In addition, 
there are many questions regarding factors which induce polydomy 
(both proximately and ultimately) and the social ramifications of 
this colony structure (see Werner et al. 1979). Leptothoracine ants 
are especially amenable to laboratory culture and provide an unu- 
sual opportunity for the experimental study of polydomy. In the 
present experiment, L. curvispinosus colonies (or colony fragments) 
were collected from individual nests in nature and provided with 
multiple artificial nests in the laboratory for an extended period of 
time. The purpose of the experiment was to discover whether colo- 
nies would become polydomous (i.e. “bud”, see below) spontane- 
ously under relatively simple laboratory conditions. 
Traditionally, the term “budding” has been used to refer to true 
colony fission in which a group of workers and one or more repro- 
ductives depart from the parental nest to form an autonomous 
daughter colony (see Wilson 1971). However, for polydomous spe- 
cies, the term “budding” has also been used to describe the forma- 
tion of non-autonomous secondary nests which at least initially may 
be queenless (e.g. Higashi 1976). In general, the relative autonomy 
of individual nests as reproductive units within polydomous colo- 
nies is debatable, and it is possible that such nests occasionally 
become isolated and achieve full autonomy (see Alloway et al. 
