Interesting video about the most poisonous (not venomous) animals, from the Cane Toad to the Striated Surgeonfish.
From the YouTube description (which includes references):
In comparison to venomous animals, poisonous animals are far and few between. It turns out having to get halfway eaten before potentially harming a predator isn’t an incredibly popular adaptation in the animal world. But the animals who managed to stick it out utilize some of the most lethal toxins on the planet, some even eclipsing what even the most venomous animals in the world are capable of. The animals on this list are ordered by increasing oral LD50 (Lethal Dose 50%), so the further up the list we go, the smaller the amount of toxin it would take for your body to fade to room temperature.
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