eli5: Why do some tiny animals contain enough venom to kill thousands of humans, isn’t that just overkill?

Question

eli5: Why do some tiny animals contain enough venom to kill thousands of humans, isn’t that just overkill?

In: 356

Answer 1

Reason is: that venom isn’t meant for you! The fact that it’s so effective at killing you is more a coincidence than anything.

They evolved with creatures that evolved resistances to their toxins. It was an arm’s race where their prey kept getting better at resisting, so they had to get better at killing.

Then you look at humans, who never had to deal with many venomous things. We were typically above those guys in the food chain, so they never really wanted to use it against us. They only do when a human gets stupid.