I'm looking for the evolution explaination for this association.
e.g. The venom-producing genes is the same genes that gives them the bright colors.
e.g. The venom-producing genes prevent the development of dull-colored skin.
Why is bright color = danger?
Maybe after a predator had a nasty experience it might start to think that anything brightly coloured might fall in the same category - that's happening in real life, and is not really evolution
however, what is evolution is that bad tasting animals can get away with being conspicuous, so for them there is no penalty for not blending in, whereas for other tasty morsels, bring conspicuous makes it more likely they'll get eaten, hence natural selection will weed out conspicuous members of a non-poisonous species, leaving only the bland ones, whereas it won't weed out poisonous species where the penalty only amounts to the occasional fatality which immediately makes the rest of the species safe from further predation
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