Characterization of cadaver decomposition islands using forensically important insects and soil metagenomics in southeast Louisiana

摘要

Topsoil microbial communities and forensically important insects are both essential in the decomposition of vertebrates. The succession of necrophilous insects and their role in the carrion habitat are well documented; however, little is known about the purpose topsoil microorganisms play in this temporary process. Research was conducted to characterize community structure of necrophilous insects and topsoil microorganisms associated with above-ground adult swine carrion for the five stages of decay. Results suggest that four shifts in topsoil microbial composition occur throughout decay, while sarcosaprophagous insects dramatically alter cadaver decomposition islands (CDIs). After a year of sampling topsoil community composition, cadaver soils had not yet returned back to parent community. The widespread availability and low-cost of next generation sequencing provided vital soil metagenomic analyses. This robust dataset of 14.98x106 rDNA sequences has the potential to provide valuable insight to law enforcement which would strengthen and add rigor to postmortem estimation.