Do piranhas ever eat each other, by mistake or otherwise?

Yes, they do sometimes cannibalise each other. As I have had seen in Nat Geo / Discovery few years back. read more

Yes, they do sometimes cannibalise each other. As I have had seen in Nat Geo / Discovery few years back. A school of piranhas in feeding frenzy will often accidentally have one or two piranhas of their school bitten by other piranhas of the same school. The injured piranhas will be seen as food by the other piranhas and the school will eat them. read more

The oddest part of eating a piranha is the bone structure. The ribs are substantial, unlike any other fish I've ever seen - like a mammal. read more