Baited transects were used to study the assemblages of ants in the Kalahari and Kara-Kum deserts and across dunes, a plain, and a dry riverbed in the Namib Desert. Species-richness was related to amount of vegetation, with the shrub desert of the Kalahari having over twice as many species as the other, more severe deserts. The point species-richness increased with overall species-richness up to an asymptote of five species. The mean number of species occurring at baits stabilized at slightly more than one species. The assemblages were inequitable, with one to three species accounting for most of the visits to baits. In the more highly vegetated deserts foraging ants examined virtually the entire desert floor on a daily basis. In the Namib, most species of ants were scavengers or omnivores; no strict granivores were found. In the other deserts only the scavenger guild was studied. In all deserts, ants dominated the scavenger guild, with other taxa coming to sardine baits only infrequently. Foraging took place more often at night and in the morning than in the middle of the day; at most sites it was more intense on the ground than in shrubs. The Kara-Kum differed in that most activity was associated with shrubs. The three most common species in the Namib were partially segregated on the basis of different times of peak activity. No overt combat was observed, and in the less speciose assemblages there was no evidence of interference. With increasing species-richness, however, there was exclusion of some species from baits, and in the Kalahari a dominance hierarchy was observed. Keywords: Namibia, Namib Desert, Kuiseb River, arid environment, environmental gradient, species richness, Camponotus detritus, Ocymyrmex barbiger, trophic specialization, activity pattern, animal communities.