Dung beetle morphological traits show intraspecific differences among four land uses in the Cerrado biome

Introduction Land-use change has tremendous negative impacts on ecosystems that often assessed by using indicator taxa, such as dung beetles. Commonly, changes in dung beetle community attributes are used to evaluate habitat disturbance. Within species, changes in functional traits could also be informative, but are rarely used. Aims/methods Our goal was to evaluate whether intraspecific variation in beetle morphology could indicate habitat disturbance, and whether changes in morphology could be a better indicator than changes in abundance. Beetles were collected in four major land uses: cerrado, eucalypt tree plantations, introduced cattle pastures, and soybean plantations. We focused on nine abundant paracoprid species. For each species in each land use, we estimated mean abundance and five morphological traits. Results Seven of the nine species showed intraspecific morphological differences due to land use, while five showed differences in abundance. All morphological traits showed effects of land-use change, but there was much variability in responses depending on species and land uses being compared. Discussion In dung beetles, intraspecific changes in phenotypically plastic morphological traits can be a more sensitive indicator of habitat disturbance than changes in abundance. Implications for insect conservation When using dung beetles as an indicator taxon, monitoring protocols could use morphological changes of a few focal species, thus avoiding massive lethal sampling which may oppose conservation goals. Also, because morphology is affected by land use, to obtain accurate results, studies using morphological traits to calculate functional community metrics, ought to use separate mean trait values for each habitat condition.