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resources. It appears that when adults can be fueled from sugar, 
more intensive foraging is possible and more brood and workers can 
be supported (Greenslade 1971; Leston 1973). 
We do not deny that species which are specialized on prey types 
evolved resource segregation from competitive pressure. In fact, 
among specialized species which forage individually for prey, we 
expect some equilibrium co-existence theory to apply (see for 
example, Davidson 1980). We assert that there is no support for the 
contention that generalists segregate the resource spectrum to 
reduce competition (Wilson 1971). Available empirical studies 
indicate that high or essentially complete overlap in food type is 
frequent (Brian 1956a, b; Pontin 1961, 1963, 1969; Yasuno 1964a, b); 
Abe 1971; Holldobler 1976a; Levieux 1977, Levings and Franks 
1982). At best, partitioning of food type can account for only a 
small part of the observed pattern of species distribution in most 
habitats. 
Habitat partitioning is a second possible method of limiting 
competitive interactions. Even in simple temperate grassland com- 
munities, co-occurring species forage at slightly different heights in 
the grass or tend to move more or less beneath the surface (Brian 
1952, 1955, 1956b; Brian et al. 1966). However, all these species are 
usually described as being interspeciflcally territorial. Tropical 
faunas are well divided into arboreal and terrestrial components; 
many specialized species are further restricted to logs, rotting leaves 
or other microhabitats (Wilson 1959b, 1971; Carroll and Janzen 
1973). Within these strata, high overlap between species resulting in 
intra- and interspecific aggression is frequently described (Carroll 
and Janzen 1973; Leston 1973; Greenslade 1975; Room 1975a, b). 
Faunas may be further subdivided by time of foraging, if by 
foraging at different times, different resources are harvested. Time 
of foraging can differ daily (nocturnal vs. diurnal, Carroll and 
Janzen 1973), seasonally ( Prenolepis imparts which forages in early 
spring and late fall, Talbot 1943, Lynch et al ., 1980) or may track 
environmental cues, such as desert species that forage after rains 
(Bernstein 1974, 1979). Although it has not been proven, it is 
probable that generalist and scavenging species forage on different 
resources if they forage at different times, if there are temporal 
components to food availability. Most dead or readily captured 
prey do not remain available for long periods, few probably persist 
even hours (Carroll and Janzen 1973, Culver 1974, Traniello 1980). 
