Venom

Snakes on the Japanese island of Ishima can't produce venom of their own, but that's not stopping them from stealing the venom of the island's toads.

The toads evolved to have toxins in their skin as a defence mechanism, but the snakes are immune to its effects. So when the snakes eat the toads, the toxins from the toad's skin are stored in glands at the back of the snake's head. The snakes then use the toxin to fight off predators.

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