Such as the tail-shedding of some lizards as a self-defense, by way of distracting its predator. Animals that do this are generally able to regrow the severed appendage. This ended up on my list thanks to news stories about recently published research into certain sea-slugs, who can decapitate themselves and regrow their entire body (CW: auto-playing video of a head crawling around its former body). Coined in 1887, after a model in either German or French, from Ancient Greek roots auto-, self + tome, severing.
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