Diet Segregation between Cohabiting Builder and Inquiline Termite Species

Daniela Faria Florencio,Paulo Fellipe Cristaldo,Ana Paula Albano Araújo,Og Desouza,Ivo Ribeiro Silva,Alessandra Marins,Cassiano Sousa Rosa,Marcelo Gustavo Lorenzo

doi:10.1371/journal.pone.0066535

Abstract

How do termite inquilines manage to cohabit termitaria along with the termite builder species? With this in mind, we analysed one of the several strategies that inquilines could use to circumvent conflicts with their hosts, namely, the use of distinct diets. We inspected overlapping patterns for the diets of several cohabiting Neotropical termite species, as inferred from carbon and nitrogen isotopic signatures for termite individuals. Cohabitant communities from distinct termitaria presented overlapping diet spaces, indicating that they exploited similar diets at the regional scale. When such communities were split into their components, full diet segregation could be observed between builders and inquilines, at regional (environment-wide) and local (termitarium) scales. Additionally, diet segregation among inquilines themselves was also observed in the vast majority of inspected termitaria. Inquiline species distribution among termitaria was not random. Environmental-wide diet similarity, coupled with local diet segregation and deterministic inquiline distribution, could denounce interactions for feeding resources. However, inquilines and builders not sharing the same termitarium, and thus not subject to potential conflicts, still exhibited distinct diets. Moreover, the areas of the builder’s diet space and that of its inquilines did not correlate negatively. Accordingly, the diet areas of builders which hosted inquilines were in average as large as the areas of builders hosting no inquilines. Such results indicate the possibility that dietary partitioning by these cohabiting termites was not majorly driven by current interactive constraints. Rather, it seems to be a result of traits previously fixed in the evolutionary past of cohabitants.

Highlights

An efficient strategy for organisms which depend on nesting is to inhabit the nest of another species, because this avoids building costs while keeping the benefits of such structures
An intriguing issue is how invaders deal with potential conflicts with the builder, especially if invaders and builders cohabit, as frequently occurring with termite inquilines and their termite hosts
In the present study we analysed the coexistence of termite builders and inquiline species in the same termitarium, in the field, with a focus on one of the mechanisms that could explain this interaction: the diet use by the species involved. To this end we evaluated diet coincidence between two builder termite species and 12 associated inquiline species, inspecting the stable isotopic signature of individuals from 14 termite nests in a savannoid ecosystem in South-eastern Brazil

Summary

Introduction

An efficient strategy for organisms which depend on nesting is to inhabit the nest of another species, because this avoids building costs while keeping the benefits of such structures. It is not surprising, that many inquiline species are spread throughout virtually all groups of animals. Intruders range from vertebrates such as birds [6] and bats [7] to a wide variety of arthropods [8,9] Most commonly, these assemblages are composed of a termite species that builds and maintains the nest, plus entire invertebrate food webs [10,11] whose members are generally referred to as termitophiles. A particular subset of these is formed by termites that inhabit termite nests and may contribute to either nest maintenance or nest decay [12], the so called inquilines [13,14,15,16,17]

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Results

Conclusion