Tropical ant species diversity and burial behaviours: impacts on carrion ecology and forensic entomology

The primary objective of this study was to investigate the diversity and abundance of ant species associated with rat carcases (Rattus norvegicus) to assess their potential impacts and applications in forensic entomology. During the study, we observed burial behaviour of two ant species, Carebara affinis and C. diversa, at the study site. The study was conducted in an urban field in Sungai Buloh, Malaysia, from 17 to 30 July 2023. Six rat carcases were used in two trials (three rats per trial), arranged in a triangular formation within the field plot. Observations were conducted three times daily to characterise ant activity and behaviour on the carcases and to collect ant specimens for identification and assessment of species abundance. A total of 11 ant species were collected from the rat carrion examined, with seven species not previously reported as utilising carrion. Notably, there was a significant change in species presence on the carcases throughout the trial periods. Carebara affinis was the dominant species on all carcases, with both major and minor workers of C. affinis and C. diversa observed burying the rat carcases using loose soil and nearby materials. This behaviour suggests resource partitioning, as burying a carcase reduces its detection by and accessibility to surface-dwelling necrophagous insects. The implications of these observations for forensic entomology are discussed.