Dolphins and Pufferfish
More chaos in nature
Apparently, "Dolphins Seem to Use Toxic Pufferfish to Get High."
Of course, pufferfish toxins are also part of why the fish is a delicacy [link to http://www.asahi.com/ajw/articles/AJ201805010006.html no longer works] in Japan.
It just goes to show that nature finds its own, chaotic, uses for things.