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Wasps seem to be best known for stinging people, ruining picnics, and generally being jerks.
But believe it or not, our lives are actually a lot better because of them.
Wasps are nuisance bugs, but they kill lots of other nuisance bugs and are important pollinators.
And scientists even think that certain compounds in wasp venom could be used as cancer therapies or new antimicrobials.
So while you might have daydreamed of humans wiping out every wasp on the planet, it would actually be a pretty terrible idea.
First, even though wasps may seem like pests themselves, they’re actually important pest control agents,
taking out other insects that are harmful to forests or crops.
Take yellow jackets — the group you probably think of when you hear the word wasp.
Although these guys will try to steal a taste of your sugary soft drink or fruit, they also collect lots of insects to feed to their larvae.
And predatory wasps like yellow jackets make up just a tiny fraction of specie of wasp.
In fact, most wasps — maybe as many as 2 million species of them — are parasitoid wasps.
And they have a whole different way of taking down insects.
Parasitoids use special venom to paralyze or zombie-fy other bugs, then lay their eggs on or inside the unfortunate host.
The host is then slowly eaten alive.
And while this is pretty gruesome, it’s also helpful for farmers.
Parasitoid wasps help control crop-destroying pests like aphids and caterpillars.
In fact, one genus — called Trichogramma — is an essential biocontrol agent.
Worldwide, hundreds of thousands of square kilometers of crops and forests are treated with these wasps to control pests.
And that translates to a lot of harmful insects.
So the next time you’re able to stock up on fresh produce at the grocery store, you might have a wasp to thank.
Besides defending them from insects, wasps are also important pollinators for certain plants, although the way they do it is often a bit weird.
For example, some species of orchids actually trick male wasps into pollinating them by looking like a hot female wasp.
And the relationship wasps have with figs is even weirder, but arguably even more important.
Figs have flowers that grow inside a mostly-enclosed shell called the syconium, and they can’t be pollinated by the wind or by most insects.
Instead, they usually have to be pollinated by a specific group of wasp species.
First, the female wasp lays her eggs inside the flowers, then dies in the syconium.
When the new wasps hatch, they stick around, grow up, and eventually mate inside the fig plant.
And yes, they are siblings -- which can lead to problems, but generally works out okay.
After mating, the blind, flightless males chew a hole in the plant so that the females can escape.
Then, the females take pollen from the fig flowers and go in search of another fig tree with another syconium.
And the process starts all over again.
This is a mutually beneficial relationship for both the insects and the trees.
And while most figs grown for human consumption can be produced without wasps, wild figs are completely dependent on them to reproduce.
These fruits are surprisingly important, too.
They’re known as a keystone species, and are consumed by over 1200 types of animals, including birds, fruit bats, and primates.
Scientists even think figs might have been a vital food source for early humans.
So by pollinating them, wasps help to maintain tropical and sub-tropical forest ecosystems all over the world.
And your family tree might also have them to thank.
Finally, wasps aren’t just worth keeping around for our plants.
If we killed them all off, we might also be missing out on an important medical resource.
See, wasp venom contains a class of peptides, which are essentially small proteins, called mastoparans.
And although they’re toxic, mastoparans could treat diseases if they’re used in the right way.
Recently, several studies have investigated whether they could be used to treat cancer.
A 2015 study from the journal Peptides found that they increased survival in a mouse model of melanoma.
And a 2016 study demonstrated that mastoparans could also kill several types of cancer cells by splitting open the cell membranes.
This peptide was more toxic to cancer cells than to healthy cells, too.
Right now, scientists aren’t sure exactly why, but they think it’s because cancer cell membranes have different properties than healthy cells.
For example, they have more of a negative electrical charge, which could attract the positively-charged mastoparan.
Several studies have even shown that these peptides might be useful antibiotics.
They’ve been shown to be effective at killing several types of bacteria and fungi that can infect humans.
In a 2017 study published in the International Journal of Antimicrobial Agents,
a mastoparan peptide was shown to significantly reduce the number of Staphylococcus aureus bacteria in mice.
This is an extremely common and potentially dangerous human pathogen, and causes everything from skin infections to pneumonia.
It can even cause blood, heart, and bone infections.
In this study, after six days of applying the mastoparan to cuts infected with the bacteria, there were significantly fewer S. aureus.
There’s a lot more research to be done before wasp venom therapies are ready to be tested on humans, but they are definitely worth investigating further.
So, even though wasps are kind of obnoxious, they play a really important role in the environment.
And maybe one day, they’ll play a big role in human health.
Which means that, as great as it would be to never have one buzzing around your next picnic or trip to the cider mill, they’re worth keeping around.
Besides, if we’re going to eliminate an animal from the earth, it should obviously be the ticks.
Thanks for watching this episode of SciShow!
If you’d like to learn more about surprisingly useful insects,
you can watch our episode on what would happen if we killed all of the world’s mosquitos,
and look forward to the one in which we talk about why ticks are good I guess!
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