‘ Soil ’ent witness: using grave soil microbial communities to aid forensic investigations

Abstract

After death, the human body becomes an active microbial ecosystem, undergoing a predictable succession that offers valuable clues for forensic investigation. This post-mortem shift, known as the thanatomicrobiome, unfolds as endogenous microbes migrate, proliferate, and respond to changing conditions within the cadaver. In a terrestrial environment, cadaveric fluids and microbial communities seep into the surrounding soil, forming a cadaver decomposition island that reshapes local chemistry and biodiversity. These interactions create the necrobiome—a dynamic ecological network whose temporal patterns can help estimate the post-mortem interval or time since death. Yet decomposition is profoundly influenced by temperature, moisture, soil type, insect activity, and other environmental factors, making standardisation a major challenge. As sequencing technologies advance and interdisciplinary research expands, decoding the post-mortem necrobiome and grave-soil microbiology offers a promising complement to the current forensic toolkit.