Why Bugs Deserve Our Respect

Fruit flies helped us win six Nobel prizes in medicine. Architects have been inspired by termite hills. Ecologist Anne Sverdrup-Thygeson explains why bugs are so essential to the world we live in.

Jessica Gross | Longreads | July 2019 | 14 minutes (3,842 words)

The ants arrived with the heat in May, streaming into my bedroom through my air conditioner. My roommate had covered hers in tape earlier that week, and I used her supplies to block any and all points of entry. Me: in. Insects: out. I can imagine the disgusted grimace I wore on my face as I taped and taped. One of the ants got caught underneath, and I remember feeling a perverse sense of retribution.

I thought about this stance a lot while reading ecologist Anne Sverdrup-Thygeson’s new book, Buzz, Sting, Bite: Why We Need Insects, which first came out in her native Norway last year. With a combination of delight and passion, Sverdrup-Thygeson makes the case that, first, insects are fascinating creatures who deserve our curiosity, and, second, they are essential to our survival and deserve our protection. As I considered the multitude of impressive and strange facts she presents (there’s a species of swallowtail butterfly with eyes on its penis, and spiders’ silk is, on a per-weight basis, six times as strong as steel!), I was transported back to childhood. I remembered how, when my parents lay new sod in the backyard, my brother and I peeled it back to find the worms slithering underneath. I remembered plucking cicada shells off trees and storing them in a shoebox, which I kept in my closet for years. Back then, bugs didn’t disgust me — they filled me with a sense of wonder.

When we spoke over the phone in early June, Sverdrup-Thygeson suggested that the disdain for insects that I and so many others have grown into isn’t natural or necessary, but a learned response. Witnessing her awe, as she put it, for these tiny creatures, it was hard not to feel that she was right. I haven’t stripped the tape from my air conditioner, but when I saw a little bug crawling up the wall of my shower a few weeks ago, I let it be, and took a moment to marvel at the way it moved with such delicate grace.

You describe in the book how, when your children were in elementary school, you would turn brown mud over with a metal sieve for them to see all the bugs, and get excited about them. So I wondered if you could start by talking about your own childhood relationship with insects. Was that something your parents instilled in you? When did this fascination begin?

Yes, I think it started when I was a kid. My family spent a lot of time in the outdoors — we picked berries and mushrooms in the fall, and we went skiing and slept out in a snow cave in the winter. We did all these things together. We also had this very simple cabin on a tiny forested island in a lake. There were no other houses on this island, and there was no electricity, so no television, of course. You pretty much had to play with whatever was there, which was nature.

So I got used to having bugs around me. Even if I sat reading, I would still sit in nature: bugs would crawl over me or fly past. When we put fire on the firewood, which was how we kept warm if it was cold, there would always be bugs in these pieces of wood. It was part of life to have bugs around, and it never occurred to me it was supposed to be annoying, or something to fear.

I also had a grandfather who was really good at showing me not insects, really, but other things in nature. He told me the names of flowers; he taught me birdcalls so I could recognize them. And I think that meant something. If someone you love shows you that nature means something to them, that transfers and has a lot of impact on a small kid.

 

Anne Sverdrup-Thygeson. (Tuva Sverdrup-Thygeson)

When did you get the idea that other people didn’t feel the same way — that other people did find bugs annoying or disgusting or scary?

Oh, it still surprises me sometimes. [Laughter] I haven’t got used to it yet, actually. Of course, I also think that yellow jackets are annoying if they come sit on my food, and I don’t like having fruit flies in my kitchen more than anybody else, but still, it’s strange to me. There are so many beautiful insects, there are so many fascinating details in terms of the way they look, the way they live, and all these interactions between them. I think insects’ immense importance in the web of nature, and therefore for us, really should make us curious about them and make us want to understand what they’re doing out there.

This is not just a descriptive, fun book — it has a very clear and urgent mission to convince people that insects are worth protection. Who is your imagined or ideal audience for the book?

Anyone who has ever met an insect. [Laughter] Which of course is pretty much everyone. I hope that, through these fun facts about insects and these strange stories, an affection for insects will sneak in on the way. That once readers realize all these fun things in their world, they will come to look at insects in a different way. Because the things that you care about, you seek to protect.

I want to talk about this affection for insects for a moment. I have a dog, and I feel this incredible tenderness toward him — I really love him. Do you love insects like that, or it’s more like you’re very curious about them, and they’re very interesting to you? Is it more like love or intellectual curiosity?

Maybe a bit of both, but also of what you would call awe, I guess. I am awed by the all the fancy details that have evolved in the relationship between flowers and insects, for instance, and how finely tuned they are. All these beautiful ways they look, all these innovative ways they can hide or pretend that they are something else. You have butterfly larvae that look like a snake to scare away any hungry birds. You have beetle larvae that actually will hide underneath a sort of wig made by their own poo, actually. All these strange things! The way that they are built: the fact that they have completely different bodies than us. I think it’s fascinating that they can have ears on their legs or, in the case of some butterflies, ears in their mouths. The fact that they can taste with their feet like a common housefly does — actually having your tongue underneath the sole of your feet! So it’s fascination, partly, and then, yes, respect for the greatness of life and all these intricate details and interconnections out there in nature.

You emphasize the numbers a lot, both in terms of how many insects there are and how diverse they are. And it is astounding. You write that there are more than two hundred million insects for every human being, that they outnumber the grains of sand on all the world’s beaches. But why is it important to understand the magnitude and diversity of insect life — what, to you, is the significance of it?

It’s like thinking about people working in a city. People do different jobs that all matter for society to run. Some clean away the waste in a city, just like insects do in nature. Some are midwives in hospital, sort of like insects do with pollination, which helps the plants have babies, to put it very simply. And insects are very important as food for other larger animals. When you understand that, it’s very easy to see that if there are less of them, a lot of birds would go to bed hungry because there wouldn’t be enough for them to eat. If you weigh the amount of insects birds eat in a year, it actually equals the weight of all us humans on the planet. If that number is halved, what will happen with the birds? You don’t need to be a biologist to understand that that is quite crucial. So the sheer numbers are important in order for insects to give us these gifts and services that they’re contributing, and that are an advantage for us humans.

As far as insect diversity goes, about half of all the species that we know and have described are insects. If you have an insect of the month calendar — which of course I do in my house here — you could actually feature a new species every month for eighty thousand years before you have to reuse a species. That gives you an impression of the richness of species of insects.

You describe, in the book, going running on forest paths and seeing how many species you can count around you. I love that: It feels like a beautiful way of communing with nature and having gratitude for being a part of it.

Most of the species that are around us in nature, we can’t really see. And if you go out in the forest or in a park near where you live and sit on a rotten log, for instance, and try to count the number of species that you see, you would probably recognize some tree species you know. You would probably recognize a few birds, maybe some flowers, if it were summer. Probably a mosquito would come along and try to get some blood from you. But the huge, huge majority of the species, you would not see.

A lot of them would actually be underneath you. A huge proportion of the species that live in a forest are inside dead trees — nothing is as living as a dead tree. There are more living cells in a tree when it is dead because all these insects and fungi and bacteria move in to recycle this tree back to fertile soil again. And there is a huge number of species down in the soil, too, which are part of what we sometimes call the brown food web. It is so basic for life on earth: It’s what keeps everything running. Plants need soil to grow, and somebody has to make that soil from the dead plants, and that’s where all these tiny ones come in — the insects and other invertebrates. And they of course need the plants to eat. This dependency has been there for so many millions of years, and it’s still what runs our world today.

There are so many incredible tidbits about insects in the book. What, of all that you included here, is most fascinating to you?

I think it is fascinating that insects, even with this tiny brain that they have — the brain of an insect is about the size of a sesame seed — can do such amazing things. Honeybees are actually able to count to four, and they can recognize human faces for several days. They don’t really understand that they see human faces, I think, but they rather think that we are some sort of strange flower, with these patterns of eyes and mouth making contrasts on what they probably think are the petals.

Bumblebees can be taught to do tricks that are very unnatural for them. If you have a little bowl of sugar water and you push it under a Plexiglas lid so they can see it but they can’t access it, and if you then attach string to these little bowls with sugary water, they can actually understand that they need to pull this string to get access to the goodies that they want. And not only that, but if you place new bumblebees that have never learned this trick in the little cage next to the ones that know the trick, just by watching the others, the new ones can learn this trick. I think it is amazing that they can do so many things that we think of as really advanced with their tiny, tiny brains and very simple bodies.

On a much larger scale, it’s fascinating that insects have been doing agriculture for a lot longer than we humans have. Termites, for instance, have actually farmed the fungi inside their nests for maybe a hundred million years. Our agricultural revolution is just ten thousand years old; they have been doing this for such a long time.

I’m sure it isn’t random that you started with a chapter on insect sex — I’m assuming that was to invite the curious reader in with as much salacious detail as possible. But there really were some incredible facts in that chapter, like the swallowtail butterfly with eyes on its penis. Who doesn’t like that? Or the water boatman, who uses his abdomen as a string and his penis as a bow — I’ve repeated that one to several friends. And then, maybe most alarmingly, there are insects where the male has a sex organ that is like a Swiss Army knife to eliminate any sperm that have arrived before. I mean, that’s ingenious and also somewhat terrifying.

This explains part of why insects are so interesting to study in biology: You can find different possible solutions. For instance, they battle between the sexes, which has parallels to our human societies; males and females doesn’t necessarily have the same goals in their relationships. The male insect wants to mate with as many females as possible, while the female actually wants get sperm from the best possible male to father her children.

I think it is quite fascinating that in the beginning, as in all sciences, most entomologists were men. It’s hard to say for sure, but it does seem that when more females came into entomology as scientists, they started to look at this battle of the sexes from a slightly different perspective. They learned that the female insect actually has a lot more say over the outcome of the mating than we thought. This is what is called cryptic female choice: If several males mate with her, she can actually control, on the inside, which sperm gets to fertilize her eggs, to a certain extent.

…when the male honeybee transfers his sperm, his male organ actually explodes. It just rips apart from his body and he dies. So that’s the last thing he does in his life. Quite brutal.

How does she do that? How does that work exactly?

Probably by muscular control on the inside. In insects, fertilization doesn’t happen immediately. The female stores the sperm in a sort of internal sperm bank, and she can do that for years; she uses the sperm when she’s fertilizing and laying her eggs, which can be a long time later. As she’s being mated, she can control whether or not she wants to transfer that sperm into this internal sperm bank. That’s how we think it works.

There are also insects that eat the male after mating. From her point of view, he has done his job, and it’s good to get some extra protein—it demands a lot of protein, laying eggs! And in several species, like in honeybees, when the male honeybee transfers his sperm, his male organ actually explodes. It just rips apart from his body and he dies. So that’s the last thing he does in his life. Quite brutal.

I also find it interesting that if you look at all the species on the planet that have a clear sex or a clear gender, the insects are so numerous so they have a large say on the total proportion between females and males. The most successful insects, the social insects — the ants, the wasps, some of the bees — are so dominated by females. Because they are so numerous, the result is that there are, in total, most likely more females on this planet than there are males.

I noticed in the book there were various instances of anthropomorphizing insects to a certain degree. And I was curious if that was an intentional technique in your writing — a strategy to invite readers in — or if it came naturally because that’s how you tend to relate to insects on your own, or a little bit of both?

It’s how I usually speak about them. I think making these parallels or giving examples makes it so much easier for people to understand. And it comes naturally to me. But at the same time I try to be very conscious of not overdoing it. We often think that it’s hard to relate to something that is very different from ourselves, that we humans relate more to animals that look a bit like ourselves, those that have fur and big brown eyes, maybe, and that we think look cute. With plants, it’s not necessarily the same, but they still have colors and they smell nice and that’s also something to relate to. But insects, you know, if you look at movies, science fiction movies, the aliens are always modeled after insects, unfortunately.

I never noticed that before.

Yes, yes. And of course there are some parallels; there are gruesome parasites in the insect world. That makes a good model if you want to invent some sort of alien species that, say, invades your body.

But still, you find all sorts of insects. Even the brutal ones are important to have nature running as it should. We need the carnivores, we need the parasites — they keep other species in check. And you also find these really beautiful examples of species that are cooperating, like this oregano plant that uses a butterfly to get rid of ants that are chewing on its roots. You can find absolutely anything that you want to look for in the insect world.

Since, as we’ve been discussing, a big part of the mission of the book is getting underneath people’s disgust for insects — or exploding it — I wanted to examine what that disgust is about in the first place. Often, when humans feel disgusted, it serves a protective function, right? “This rotten thing is disgusting because it would make me feel sick to eat it.” So I wondered if there some kind of adaptive mechanism to it, where it’s trying to protect us from an insect that might be poisonous, or if you think it’s more of a learned response?

It is of course hard to say for sure, but there are not many insects that are poisonous. It makes more sense with spiders and snakes. So I think the majority of the reason people feel disgust for insects today is learned. Most kids are fascinated by small creatures, maybe because they’re even smaller than themselves, which is nice. When you’re little, it’s nice to have something even smaller than yourself so you feel a bit big. Kids lift up a rock or the bark of a dead tree and have this sense of wonder and curiosity that we grown-ups lose sometime along the way, unfortunately. On our way to adulthood, we either lose interest or are told that this is something we should find bothersome or disgusting. And that’s why one of the things we can do, if we want to spread some respect for these creatures, is to give them a bit more credit and honor for all the good things that they do for us. This is such an easy thing to do. It doesn’t cost any money, you don’t have to have a garden and plant flowers, it’s just about how you talk about insects to your kids or grandchildren or neighbors or colleagues at work. I think that can have a really huge effect. We should appreciate them both because they are beautiful and fascinating and because we actually need them. We are one hundred percent dependent on them. So for our own sake, we should care about insects.

Could you outline some of the ways in which we humans rely on insects?

They are vital as janitors in nature, doing this recycling of dead trees, dead plants, dead animals and dung. Without that process, nature would sort of stop. They’re really important in pollinating both the wildflowers and our crops. If we lost a high number of them, it would definitely affect our food security.

They are also really important as food for others. So it would have knock-on effects on a lot of other, larger animals if they got lost. They’re sort of a glue in nature — a missing link between plants and carnivores. A lot of big carnivores depend on insects because they can’t eat the plants directly. They also give us products that we need, from honey to shellac.

And finally, insects inspire us in many ways. Architects have used termite hills as models for buildings that use a lot less electricity for heating and for air conditioning. Fruit flies have been part of six Nobel Prizes in medicine because they are so good to use in the lab. And there are so many more things we can learn from them.

You write that a quarter of all insects may be under threat of extinction at this point. So this is a dire matter.

Since the book came out in Norway, which is about a year ago now, a few more really scary scientific papers have come out giving more examples of the decline of insects in different parts of the world. Nature is adaptive, evolution happens all the time, but the risk now is that we’re changing so many things — through intensive land use, climate change, introducing species, moving species around, using pesticides — in such a short time. So the question is whether insects and other biodiversity will be able to adapt quickly enough to come along with us into this new future. I like to think of nature as a hammock, where all the species and the places they live make up the threads. When insects and other species decline in numbers or go extinct, it’s like we’re making holes or pulling out threads in this hammock. This hammock is crucial because we humans are resting in it; it’s the foundation for our civilization. And it might work fine as long as there are just a few loose threads. We can still rest peacefully in that hammock. But if we pull out too many threads, at some point the whole hammock will unravel. And that’s when we really don’t know what will happen. But it’s quite certain that it will be more difficult then for us to get sufficient food and clean water and good health to all the humans on this planet.

I would also add that, aside from the benefit to us, there’s the ethical point of taking care of insects as a species. We humans are so lucky. We live in this one single spot in the universe where we know that there is life. I think that gives us the responsibility to step down a little bit in our resource consumption and prioritize the way we treat nature so that all these millions of other tiny species will have a possibility to live out their strange lives.

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Jessica Gross is a writer based in New York City.