Does a poisonous snake die if it bites itself?

It depends on the snakes.

Many snakes are immune to the venomous snakes that live in the same geographic areas. Most snakes, if not all, are immune to their own venom, but this is an evolutionary process produced over the past 100 million years. If two snakes of the same species bit each other, there would most likely be no effect from the venom.

If two snakes of different species, from different parts of the world bit each other, it is very likely that both snakes would experience a strong reaction to the other's venom.

Biting a venomous snake is not harmful as long as the stored venom is avoided. Even then, venom is not dangerous if swallowed, but is very dangerous if it enters an open wound on the biter's skin or mouth. Many birds, snakes and other animals kill and eat venomous snakes. Some have varying degrees of immunity and some are just careful.

The pig is believed to get its immunity to snake bite from its thick layer of fat.

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