I've never before heard of a snake biting itself! The Daily Mail reports:
Creepy video shows the moment that a decapitated copperhead snake bites itself - thereby making 100 percent sure of its own death.
Huntsville, Alabama resident Sam Billiter posted the unusual video to his Facebook page on Monday inviting people to watch the snakes disconcerting reaction to its own body.
Finding the venomous snake in his woodpile outside his home, Billiter took the decision to kill it rather than run the risk of his wife, four-year-old boy or dog come to harm.
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While it may seem freakish, many snakes still have reflexes hours after their death and some have been known to strike and kill even after they have technically died.
There's more at the link. Here's the video clip. Warning - if you're sensitive about such things, you might prefer not to watch this one. Seriously.