What would happen if we didn't have wasps?

Answer 1

"As a group, wasps provide extraordinarily important ecological services, including pollination, predation, and parasitism. Put simply, without wasps we would be overrun with insect pests, and we would have no Fig Newtons.

I suspect, however, that you weren't thinking about things like fig wasps when you started wondering why we need wasps. You were probably aggravated by the yellowjackets hanging around your garbage cans, or terrified by the huge hornets' nest you just discovered in the shrub near your pool.

We take notice of the social wasps because they build visible nests, often close to our own homes, and because they will defend these nests aggressively.

Hornets and paper wasps prey on other insects, and help keep pest insect populations under control. It takes a lot of bugs to feed a hungry brood. Both hornets and paper wasps provide vital pest control services.

The University of Florence researchers found that wasps and hornets feed on late season grapes, which are rich in wild yeast. The yeast survives the winter in the stomachs of hibernating queen wasps, and is passed on to their offspring when the mother wasps regurgitate food for their young. The new generation of wasps carries the yeast back to the next season's grapes. So raise your glass to the wasps and hornets!

Yellowjacket don't get quite as much credit for being beneficial, although they should. Yellowjackets mostly scavenge dead insects to feed their offspring.

We do need these services, too, of course. What would the world be like if all the dead bugs just piled up? Unfortunately, their scavenging habits and their love of sugar puts them in close proximity to people, which almost never ends well for the yellowjacket or the person."

Source: Nuisance Wasps and Bees, Colorado State University Extension, accessed September 11, 2012