There are quadrillions of insects on earth. Anne Sverdrup-Thygeson, a professor of conservation biology at the Norwegian University of Life Sciences, estimates they outnumber human beings by a factor of 200 million to one.
But as awe-inspiring as that figure seems, the world's insect population is actually falling, Sverdrup-Thygeson notes.
"Our land use is changing a lot," she says. "We have removed a lot of flower meadows, dead trees in forests which ... [are] very important places for insects to live."
In her new book, Buzz, Sting, Bite: Why We Need Insects, Sverdrup-Thygeson writes about the dangers people face as the numbers of insects drop. The creatures play a vital role in pollinating crops, eating discarded food left behind on city streets, and feeding other animals in the food chain.
Sverdrup-Thygeson imagines all the species of the planet as a hammock in which insects act as a substantial part of the thread: "We can still rest in this hammock with a few loose threads and a few holes," she says. "But if too many threads will loosen, the whole fabric will unravel, and that will have a really serious effect for us humans as well."
On how climate change can cause "ecological mismatch"
One of the things that is really scary with climate change is this risk of ecological mismatch, which means, for instance, if you think of insects pollinating flowers, you will need the flowers to be flowering at the same point of time as the insects are swarming — as the insects are out flying.
If one of these processes is governed by temperature — like, say, the insects will swarm when there is a certain temperature — maybe the flowering of the plants are more governed by daylight. And then you can imagine that with climate change now we are changing temperatures, but we are not changing daylight hours. And this means that these processes can move apart. And what happens then if the flowers are flowering at a stage where the insects are not flying yet, or the birds have chicks needing insects for food at this point of time when the insects are not flying? These things, I think, are really scary.
On the ripple effect of the insect population declining
Insect-eating birds depend on insects in order to survive. We know that if you take the amount or the weight of the insects that the birds on this planet eat in a year, that weight is actually equal to the weight of all humans on this planet. And then you understand that if insects are declining, birds will decline; freshwater fish will decline; bats will decline; some mammals will decline. And it's this sort of ripple effect that is one of the things that we might see happening if this insect decline is continuing and if it's like a global trend.
On insects as the new sushi
They are really high in protein — like certain types of insects can contain almost 70 percent protein, which is extremely high. Your normal beef would be [about] 20 percent. ... And this means that in a food security perspective, they can be really important. The United Nations has spent quite a lot of time researching insects as food, especially for children and also for pregnant women that can't move that far from their homes. They can be really important as a source of protein in certain communities and countries of the world, and even in the West. ...
You wouldn't eat a sheep with the wool on, so, of course, also with insects — they become much nicer to eat if you actually turn them into some foodstuff that doesn't look like a complete insect with legs and wings sticking out. ... You can make protein bars, for instance. That's definitely a way to go, or biscuits or something. ...
It's a bit comparable to eating sushi in a way I think. Because when sushi came along, most of us thought it was a bit strange to eat raw fish. It's not something that we were that used to in the West. But then it just took a few years and then it has switched completely, and now everybody is eating sushi. No one thinks that strange anymore. So maybe insects can be the new sushi in a few years.
On insects as the janitors of our cities
There's this study ... [of] ants in Manhattan, and they estimated that for each person living in Manhattan there would be about 2,000 ants for each person — and that's actually something that you should be happy about, because they eat a lot of junk food remains that people drop on the pavement or leave on the lawn in the parks. And they sort of calculated that these scraps of junk food that [are] put away by the ants of Manhattan, they add up to the equivalent of 60,000 hotdogs every year. And just imagine if that would sort of sit around not being removed. That would not be very nice. So I think we should be glad that they're there to clean away stuff that we don't want to have on our pavements or in the parks.
On how cockroaches could be used in the future to rescue people from a collapsed building
They are incredibly good at moving around. They can move at high speeds and they can get through different sort of hindrances, crawl over things, climb through things. Researchers have been trying to make use of that so that cockroaches can actually come to your rescue if you're trapped inside a collapsed building, or a building with a lot of pollution of some kind — like radioactive pollution. What they do then is to mount a little backpack on the cockroaches and they attach it to the antennas and to the back of the cockroach. And by using tiny electrical triggers they can remotely control several cockroaches and send them into a building. And in that way they can map the remains of the building and they can also have a microphone there in this little backpack, so that if people are trapped in there and they are crying for help, this can be recorded. And the people that are trying to rescue [them], they can come to the rescue right to the spot where people are trapped.
Lauren Krenzel and Mooj Zadie produced and edited this interview for broadcast. Bridget Bentz, Molly Seavy-Nesper and Deborah Franklin adapted it for the Web.