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Using pig carcasses exposed over 3 years in rural fields during spring, summer, and fall, we studied the relationship between decomposition stages and degree-day accumulation (i) to verify the predictability of the decomposition stages used in forensic entomology to document carcass decomposition and (ii) to build a degree-day accumulation model applicable to various decomposition-related processes. Results indicate that the decomposition stages can be predicted with accuracy from temperature records and that a reliable degree-day index can be developed to study decomposition-related processes. The development of degree-day indices opens new doors for researchers and allows for the application of inferential tools unaffected by climatic variability, as well as for the inclusion of statistics in a science that is primarily descriptive and in need of validation methods in courtroom proceedings.

Forensic entomology is an inferential science because postmortem interval estimates are based on the extrapolation of results obtained in field or laboratory settings. Although enormous gains in scientific understanding and methodological practice have been made in forensic entomology over the last few decades, a majority of the field studies we reviewed do not meet the standards for inference, which are 1) adequate replication, 2) independence of experimental units, and 3) experimental conditions that capture a representative range of natural variability. Using a mock case-study approach, we identify design flaws in field and lab experiments and suggest methodological solutions for increasing inference strength that can inform future casework. Suggestions for improving data reporting in future field studies are also proposed.

Ecological succession is arguably the most enduring contribution of plant ecologists and its origins have never been contested. However, we show that French entomologist Pierre Mégnin, while collaborating with medical examiners in the late 1800s, advanced the first formal definition and testable mechanism of ecological succession. This discovery gave birth to the twin disciplines of carrion ecology and forensic entomology. As a novel case of multiple independent discovery, we chronicle how the disciplines of plant and carrion ecology (including forensic entomology) accumulated strikingly similar parallel histories and contributions. In the 1900s, the two groups diverged in methodology and purpose, with carrion ecologists and forensic entomologists focusing mostly on case reports and observational studies instead of hypothesis testing. Momentum is currently growing, however, to develop the ecological framework of forensic entomology and advance carrion ecology theory. Researchers are recognizing the potential of carcasses as subjects for testing not only succession mechanisms (without assuming space-for-time substitution), but also aggregation and coexistence models, diversity-ecosystem function relationships, and the dynamics of pulsed resources. By comparing the contributions of plant and carrion ecologists, we hope to stimulate future crossover research that leads to a general theory of ecological succession.