According to an internet search, there is no butterfly that is so poisonous that it would kill a human. There are butterflies that are extremely distasteful to birds and other such predators due to the larva's consumption of poisonous plants. The Monarch butterfly is a well-known example of that. The larva eat milkweed.
no
yes they are poison
Anything that leads to survival and reproductive success is, generally, an intrinsic adaption. If a butterfly were to mimic another butterfly that was poison to it's predators then those self same predators would tend to leave the non-poison butterfly alone as well as the poison butterfly thus leading to survival and reproductive success for the mimic.
No.
it has poison on its wings
if you don't eat it?
No, it could not, because the poison was specifically designed to kill rats, and was developed as a rat poison/killer, not a human poison/killer. It would still be considered rat poison, even if the human died from the rat poison.
The butterfly in no way harms human activities. The butterfly is beneficial to humans because it helps to pollinate the flower.
No.
no geckos can not spit poison!
Poisonous butterflies live on poisonous plants and collect the compounds from their host when the are a caterpillar (larva). Poisonous butterflies are often imitated (mimicry) by non-poisonous species, so the difference is sometimes very hard to see.
No, humans are not poisonious.