bogleech:

This is one of the most common questions I get about insects. Everybody seems to want to hate wasps, just because they’re very good at killing other animals and protecting themselves – which is true of almost all predators, isn’t it? People idolize dolphins, tigers, wolves, bears, hawks, often even the much-demonized snakes these days (I’m glad that’s turned around), but they’re still quick to dismiss wasps as evil just for being well-defended hunters.

That’s also the answer to the original question: wasps are basically keystone carnivores of the insect world. Frogs, bats, spiders and countless others all do their part, but wasps are the most high-efficiency regulator of other arthropods, ESPECIALLY for plant eating caterpillars. Take away the wasps, and everything else suffers. Even the insects they kill suffer, as their uncontrolled population depletes their own resources and leads to outbreaks of disease.

Most wasps, of course, are totally harmless to humans anyway. Most are tiny, specialized parasites who lay their eggs in other insects and couldn’t sting us if they wanted, but the bigger, nest-building, stinging wasps are just as important. One nest of hornets can perform critical population control for an acre of land or more, and yellow jackets are essential scavengers, especially of dead insects.

Wasps also pollinate flowers, just like bees do, and in fact many flowering plants are only pollinated by wasps – usually just one species whose pheromones they imitate.

The aggression of wasps is generally highly exaggerated. They don’t “want” to sting you, because they run a lot of risk themselves in doing so, but they will if they’re absolutely convinced you want to eat their babies – and nothing convinces them more than if you seem to show “excitement” at the sight of them. (In other words, if wasps make you nervous, they’re going to interpret your elevated breathing and movements as hostility)

Smaller wasp nests, like those of paper wasps, are very prone to becoming “tame,” getting used to human presence as long as it doesn’t disturb them. This can get to the point where you can walk right up and touch the nest and they only get a little curious. If you bring them food with some regularity, this goes faster and they might end up eating right out of your hands.

Plain old honeybees actually kill quite a few more people than any wasps – and that thing about horses is just totally untrue, horses can live through quite a few more hornet stings than an angry swarm will even deliver.

Sadly all the unnecessary hate and fear has rendered many hornets critically endangered, as people even go out of their way to destroy nests they find in the wild, where they naturally belong.