Most people know wasps as stinging, swarming pests that show up unexpectedly at their picnics or in their eaves. A single yellowjacket nest can hold thousands of insects.
What’s the point of them? “If I had a pound for every time somebody had asked me that,” says Seirian Sumner, a professor of behavioral ecology at University College London, “I’d be a millionaire.”
Sumner thinks wasps need a better PR team. And with no one else stepping up, she’s volunteered for the role. In her book “Endless Forms: The Secret World of Wasps,” published in the United States this week, Sumner hopes to convince readers that these hated bugs are amazing.
For starters, anyone with a yard or garden should consider wasps a friend. Adult wasps hunt any kind of bug they can find: mosquitoes, flies, those caterpillars eating your lettuce. “They are your natural pest controllers,” Sumner says. “They are your route to a more sustainable way of gardening and farming.”
Surprisingly, though, they don’t keep any of the fresh-killed food for themselves. They save it for their larvae — maybe feeding the babies directly or burying the food and laying their eggs on it, depending on the species. The adults are content to be vegetarians, sipping on flower nectar or nibbling pollen. As they fly from bloom to bloom, they also pollinate the plants, just the way bees do.
A wasp’s exact role in your garden depends on its type, and there are a jaw-dropping variety of wasps on Earth: around 100,000 species, with more species likely waiting to be discovered.
Most of these are not the familiar yellow-and-black kind but species called parasitoids. You may spot them on your flowers as little black insects that resemble skinny flies, Sumner says.
Parasitoids use a piercing egg-laying tube to deposit their eggs inside the bodies of living insects. When the eggs hatch, the larvae eat the host bug from the inside out. This is another way in which wasps control pests. Some wasps, called hyperparasitoids, even lay their eggs inside different parasitoid wasps.
Other types of wasps, though, have a more gentle lifestyle. Species called fig wasps have evolved mutually beneficial relationships with fig trees. These wasps live out most of their life cycle inside a fig and in return for the housing, pollinate the tree’s flowers.
Still other wasps, such as the yellowjackets, live in complex societies. Just like ants and honeybees, the worker wasps are sisters that cooperate to defend the hive, gather food, and tend the eggs laid by the queen.
In fact, ants and bees are both descended from wasps. That means wasps have a lot to tell scientists about the evolutionary origins of these other insects. Despite that, wasps are “massively overlooked,” Sumner says. “There’s been a huge amount of research into ants and bees. And yet wasps are the root of all of those.”
To raise wasp appreciation, Sumner’s lab launched a citizen science project five years ago called the Big Wasp Survey. “To be honest, it was set up as a kind of publicity stunt,” Sumner says. The scientists provided instructions for building a wasp trap out of an empty plastic bottle and a splash of beer or orange juice and asked people to mail them the wasps that they caught at home.
The project “kind of exploded,” Sumner says. Thousands of people across Britain participated. “We ended up generating data that was of scientific value as well,” she says, such as about the distribution of different social wasp species.
“Over the years, I’ve realized that I have to do more than just pure research,” Sumner says. When it comes to wasps, she says, “I have to bridge the gap between the science and the people. Because it’s the people that are the problem.”
Elizabeth Preston is a science journalist in the Boston area.