Data from: Diet shifts by adult flightless dung beetles Circellium bacchus, revealed using DNA metabarcoding, reflect complex life histories

Life history changes may change resource use. Such shifts are not well
understood in the dung beetles, despite recognized differences in larval
and adult feeding ability. We use the flightless dung beetle Circellium
bacchus to explore such shifts, identifying dung sources of adults using
DNA metabarcoding, and comparing these with published accounts of larval
dung sources. C. bacchus is traditionally considered to specialise on the
dung of large herbivores for both larval and adult feeding. We
successfully extracted mammal DNA from 151 adult C. bacchus fecal samples,
representing 16 mammal species (ranging from elephants to small rodents),
many of which are hitherto undescribed in the diet. Adult C. bacchus
showed clear dung source preferences, especially for large herbivores
inhabiting dense-cover vegetation. Our approach also confirmed the
presence of cryptic taxa in the study area, and we propose this may be
used for biodiversity survey and monitoring purposes. Murid rodent feces
were the most commonly fed-upon dung source (77.5%) for adult C. bacchus,
differing markedly from the large and megaherbivore dung sources used for
larval rearing. These findings support the hypothesis of life
history-specific shifts in resource use in dung beetles, and reveal a
hitherto unsuspected, but ecologically important, role of these dung
beetles in consuming rodent feces. The differences in feeding abilities of
the larval and adult life history stages have profound consequences for
their resource use and foraging strategies, and hence the ecological role
of dung beetles. This principle and its ecological consequences should be
explored in other scarabaeids.