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[Vol. 88 
reported cases of overdispersion in temperate ground ant com- 
munities dominated by relatively few generalist species (most species 
of the genera Myrmica, Tetramorium, Lasius, Aphaenogaster, some 
Formica; Table 1). Some species are placed here somewhat ar- 
bitrarily because good foraging ecology data are not available. 
In more complex (i.e., non-uniform) habitats, the pattern of nest 
spacing is reported to be directly related to environmental condi- 
tions. Lasius flavus, which has been intensively studied in several 
European habitats, displays different nest distributions between 
locations. Waloff and Blackith (1962; Table 1) found that nests were 
overdispersed in a high density population and tended toward 
randomness in a low density population. In a wet, low pasture with 
limited nest sites, nests were also overdispersed (Blackith et al., 
1963, Table 1). With Myrmica rubra present in a low density 
population, L. flavus was randomly distributed (Elmes 1974). 
However, the partial segregation of species indicated that both 
intra- and interspecific interactions were present; M. rubra nests 
were more overdispersed than potential nest sites (Table 1). Similar 
patterns have been noted in other species. Petal (1972) showed that 
the pattern of distribution in Myrmica laevinodis depended upon 
the scale with which the species was examined. Within the habitat, 
nests were clumped, but within clumps of nests on a small scale, 
nests were either overdispersed or randomly distributed. In another 
study, Petal (1977) linked observed nest distribution and the avail- 
able food supply in Myrmica lemanica. In a year with low food 
abundance, nests were overdispersed; when food was abundant, nest 
distribution was random, tending to aggregation. Petal did not state 
if she distinguished between nests and nest openings by testing 
aggressive responses between colonies. However, overall nest density 
remained approximately the same. Most other studies have assumed 
but not demonstrated the correlation between food abundance and 
nest dispersion patterns. 
Within colonies with multiple nest entrances, the distance be- 
tween nest entrances should be approximately 2 r and nest entrances 
should be overdispersed if avoiding redundant search is the under- 
lying cause of polydomy. This appears to be the case in Lasius 
neoniger. Each nest is composed of a series of nest entrances which 
are overdispersed within a colony (Traniello 1980). L. neoniger is 
unable to retrieve prey effectively further than approximately 15 cm 
from any given nest opening due to interference from other species 
