Direct relationship between evapotranspiration rate (ETO) and vertebrate decomposition rate.

When vertebrate scavenging is excluded, the Evapotranspiration Rate (ETo) of a given geographic region directly regulates the decomposition rate of unclothed vertebrate carrion, with any deviation attributed to insect activity. We conducted four decomposition experiments using pig carrion (Sus scrofa domesticus) over the span of two years (2018-2020) at a location in Davis, California. We used ETo, a variable that accounts for five climatic parameters (wind, temperature, humidity, solar radiation, and altitude) as the rate-determining variable of the decomposition process. We found ETo to have a strong (R2 = 0.98) predictive relationship with the decomposition rate. To account for maggot activity decomposing the carrion, we measured maggot weight in 2019 and 2020 using a novel method, and in 2020 we used FLIR imagery to measure maggot mass temperatures as a surrogate measurement of total maggot activity. Maggot activity was a significant predictor (p < 0.0001) of the decomposition rate, while maggot weight was not (p > 0.1). We hope to show the forensic entomology community the potential of using ETo. Future projects can incorporate ETo as a baseline to decomposition studies to determine if ETo remains the most accurate descriptor of decomposition and ultimately increase certainty in the Postmortem Interval (PMI).

A novel approach to combatting proboscidean ivory trafficking using a multiplex High-Resolution Melt (M-HRM) assay.

To support efforts in prosecuting wildlife crimes, we developed and validated a multiplex High-Resolution Melt (M-HRM) assay for the identification of proboscidean taxa commonly required to be identified or excluded in ivory seizures and forensic casework: Asian elephant (Elephas maximus), African elephant (Loxodonta spp.), mammoth (Mammuthus spp.), and mastodon (Mammut spp.). Five hundred and fifty (550) blood, tissue, and ivory samples from individuals of these 4 proboscidean taxa were used to develop and validate the 2 proboscidean-specific mitochondrial sites targeted by this assay. The 28-basepair (bp) 16S ribosomal RNA (rRNA) and 54-bp cytochrome b (Cytb) gene segments yield a combination of melt peaks that create composite melt profiles unique to each of the 4 proboscidean taxa. Wildlife forensic laboratories can use this sensitive, rapid, and cost-effective assay to assist efforts to combat the unlawful commercialization of proboscidean ivory and to stop the poaching crisis leading to the decline of these ivory-bearing species in the wild.