Numerous factors affect distribution and abundance. Due to their intimate host association, pollinating fig wasps areexpected to occupy the entire distribution of their host fig. An understanding of the physiology of fig wasp species and thefactors affecting adult survival are important for understanding and explaining wasp abundance and distribution patterns.We examine distribution and abundance patterns of a fig tree fig wasp system in which the non-pollinator (Ceratosolengalili ) has been reported to be rarer than the pollinator (Ceratosolen arabicus) in drier areas due to lower desiccationtolerance. Both species are closely related and utilise the same oviposition sites on Ficus sycomorus. We used ecologicalniche modelling to determine whether C. galili covers the range of F. sycomorus and whether it is consistently rarer thanC. arabicus. We examined emergence times, critical thermal limits, desiccation and starvation tolerances of the wasps. Thesuggested rarity of C. galili relates to lower abundance in certain months and at certain localities but a similar number ofoccurrence records within the distributional range (except in arid regions, e.g. Namibia). In contrast to C. galili,C. arabicus has a wider thermal range, lives longer under hydrating and dehydrating conditions and is a nocturnal flier.The synergistic effect of physiological tolerances and flight time differences exacerbate the less favourable conditionsavailable to C. galili during flight and location of receptive figs. These factors enable C. arabicus to survive for longer thanC. galili, meaning that they are more likely to disperse to trees that are flowering further away in space and time.Combining correlative and mechanistic approaches has aided us in understanding the ecological niches of these species.
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