Some Animal Planet special or other - was it called "World's Most Inexplicable Insects", maybe, or "Top 10 'You're F*cking Joking' Bugs"? - recently schooled me on a certain cricket species. I can't recall where exactly it resides, geographically; Southeast Asia, I believe. It's a cave dweller. The caves it resides in are devoid of other animal life, but used to be home to cave bears and giant sloths, eons ago. When its caves had other denizens, this cricket fed on the other species' dropped food, or dander, or something similarly unsavory. Now that it inhabits these caves sans chums, and thus sans food sources, it has had to adjust, evolutionarily.

It eats its own legs. It eats a leg, then the eaten leg regenerates itself.

This is true.

I do not recommend thinking about this cricket if you've got a weakness for symbolism and/or macabre brooding. Especially the symbolism part, and doubly especially if you indulge in any illicit substances which enhance one's propensity toward overarching metaphor and saying things like "The cricket is us."