PT Journal AU Bourguignon, T Sobotnik, J Lepoint, G Martin, J Roisin, Y TI Niche differentiation among neotropical soldierless soil-feeding termites revealed by stable isotope ratios SO Soil Biology & Biochemistry JI Soil Biol. Biochem. PY 2009 BP 2038 EP 2043 VL 41 IS 10 DE Anoplotermes; Termitidae; Isoptera; Resource partitioning; Food web; Decomposition gradient AB Termites represent one of the most abundant belowground animal taxa in tropical rainforests, where their species richness is much higher than in any other ecosystem. This high diversity in soil ecosystems is however difficult to explain by classical Hutchinsonian niche theory, as there is little evidence for spatial or temporal separation between species. Using delta C-13 and delta N-15 isotopic ratios, we tested if resource partitioning along the humification gradient occurs; in neotropical soldierless termites of the Anoplotermes-group. Two distinct sites were investigated to check if interspecific differences are transposable between sites. Significant differences in delta N-15 were found between species of the Anoplotermes-group. Although some species displayed higher intersite delta N-15 variation than others, species-average delta N-15 values for both sites were highly correlated, showing that sympatric soldierless soil-feeding termites feed on distinct components of the soil. Our data also suggest that some species are more likely to shift along this gradient than others, in response to overall habitat conditions or to the presence of competitors. Feeding niche differentiation can therefore account for the high species richness and diversity of soldierless soil-feeding termites in neotropical rainforests. (C) 2009 Elsevier Ltd. All rights reserved. ER