Collecting insects from dead bodies is a staple of crime shows.
Blow flies lay eggs within a minute of death, summoned by chemicals with the fabulous names of putrescine and cadaverine. The age of a maggot predicts the time someone began their dirt nap. Elaborate mathematical formulas are used for calculating maggot age. Plug in the size of the maggots, body temperature, and environmental temperature.
[F]orensic equations used to calculate time of death don’t factor in maggot heat, which could be a problem.
Maggot heat, as in the heat produced by massive amounts of maggots. Get enough maggots together and get enough heat, and unfortunately, they just boil alive.
I say “unfortunately” because the alternative – spontaneous maggot ball combustion – would have been pretty cool.
[T]hey recorded how much heat maggots in groups of up to 2,500 generated.
Peak Temperature = [ 23.8 + 0.0046 * Mass size]
So I was able to calculate that 100,000 maggots (about 7 pounds), would have a predicted temperature of 484ºC (902ºF).
Maggots also produce metabolic heat by feeding on decaying flesh, and muscular heat by crawling around. Because masses are so densely packed, their bodies may serve as insulators, helping to build up and preserve heat. Larval tunneling through body tissues acts like a “bubbler” in an aquarium. They aerate the flesh, so oxygen levels are maintained.