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In order to understand how the apparent freedom of individual movements can concur with social order in a colony, we investigated spatial relationships between foundresses, workers and immature brood in a paper wasp. This is the first time an ecological analytical approach (home range analysis) has been employed to describe small scale spatial use in a social context. In this study, home range was not used in its strictly ecological sense, but rather applied to the comb. Our results show that the positions individual wasps assumed on Polistes dominulus combs are spatially structured. Workers and foundresses do not occupy the comb in random distribution, but rather follow predictable spatial patterns. Each active wasp has its own spatial fidelity area, at least over a 1 d observation period, spending the majority of its time within a very small area averaging approx. 12% of the comb but occasionally it may cover an area of up to 50% of the comb surface. Dominant females occupied a significantly smaller area that either subordinate foundresses or workers. Areas patrolled by workers varied in shape and size, with no relation to time spent on the comb, wasp density or position of immature brood. All the wasps clumped around the dominant female, who proved to be the only individual affected by cell content. Nevertheless, although the wasps tended to clump together, average superimposition rates among nest-mates was very low (higher in workers than foundresses), suggesting that the wasps limit each other’s individual spaces. [ABSTRACT FROM AUTHOR]

In animals, restlessness is a strategy to fulfil a goal within a narrow seasonal window when ecological and physiological constraints require the performance of certain fundamental events. Although restlessness can be expected in parasitic species that have their biological cycle similar to that of the host, no ‘urge to parasitize’ has thus far been demonstrated in any host-parasite pair. The paper wasp, Polistes sulcifer, is a social parasite that has lost the nest-building ability and marked by the absence of the worker caste; it depends on a congeneric host species to reproduce. Host colony usurpation is successful when it occurs in a well-defined seasonal window. The short time available for host-nest usurpation might lead to parasite restlessness that overlaps this period. Under controlled laboratory conditions, we demonstrated that the parasite females exhibit ‘usurpation restlessness’ during the period in which field usurpations occur. Additional experiments showed that both this period and laboratory temperature influence the parasite’s ‘urge to usurp’. [ABSTRACT FROM AUTHOR]