Chemical reactions can cause decomposing bodies to twitch, move, and groan.
Recently, scientists were able to revitalize a bacteria that's been dead for over 120,000 years! Are humans next?
Bugs flip when they die because their legs return to what is called the "position of flexion."
Also, when birds are trapped over and over again through the years, this gives scientists a sense of their lifespan. How else can you know if the cardinal at your bird feeder is the same one that was there last year?
The chemicals that cause this reaction are stored in our nerve endings, and when we die, they’re gradually released.