The world without insects is scary – biologist
Our planet’s biodiversity has long been crying for help. Hundreds of species could vanish off the face of the Earth, and we are talking end of this century, Bees are one of them. What would their extinction mean for our future? We talk with Dave Goulson, Professor of Biology at the University of Sussex and author of ‘Silent Earth: Averting the Insect Apocalypse.’
Sophie Shevardnadze: Dave Goulson, Professor of Biology at the University of Sussex and author of ‘Silent Earth: Averting the Insect Apocalypse.’ Welcome to our show. Great to have you with us.
Dave Golson: Pleasure to be here.
SS: Alright, so when you tell someone that populations of insects are going down, and the most frequent reaction would be what, like, ‘Oh, well, whatever, there would be less of that annoying buzzing and stinging.’ Can you summarize for us what exactly happens when insects disappear? And why we really shouldn't be happy if they disappear?
DG: Yeah, of course. I mean, you're absolutely correct. Many people really don't like insects very much and they think it's a good thing if there are fewer insects. But actually, it's a disaster. So insects make up the bulk of all life on earth. We've named so far about 1.5 million species of animal and plant on our planet, of which 1.1 million are different types of insects. They are biodiversity really or a big chunk of it. And they’re food for many of the organisms that aren't insects. So lots of birds and bats and small mammals and freshwater fish and amphibians and lizards, they all eat insects, so if the insects go, they will go. But insects also do lots of other things that are really important like they control crop pests. They are really important in recycling, they recycle dead bodies, dead trees, leaves, all sorts of organic material they break down. They keep the soil healthy, they distribute seeds. And of course, the thing that is perhaps most familiar – they pollinate. So the large majority of all the plants in the world need pollinating by insects, they wouldn't set any seed and without them, they would disappear. And approximately three-quarters of all the crops that we humans grow, depend upon insect pollinators. Everything from strawberries and raspberries and apples to pumpkins and blueberries and tomatoes and chilli peppers, and even coffee and chocolate depend upon insect pollinators. So your life would be pretty dire without all those foods and the honest truth is, we couldn't feed everybody without insects. So whether you love them or loathe them, we really do need insects.
SS: According to the European Parliament data, about a third of bees and butterfly populations are declining and 10% of bees and butterfly species are actually endangered. Massive amounts of insects have disappeared in the past few decades alone. So what kind of environmental effects are we looking at already?
DG: Well, if we don't do something about it pretty urgently, we're looking at the kind of collapse of the functioning of ecosystems that essentially grind to a halt if we continue to lose insects, not just the extinctions, but it's the lack, the falls in abundance of species that are probably really most crucial. There's been some really dramatic evidence, for example, from Germany, where a long study found that the biomass of flying insects, the weight of flying insects fell by 76% in the last 26 years. So insects are just becoming much, much less common, which means all the jobs that they do are not being done anymore. And that is the real danger. And that's what's going to impact on us.
SS: Do we actually know of the insect species that have already gone extinct, and they're never coming back because of us?
DG: Yeah, there are some and probably a great number of them that we don't know about. It's really interesting, actually, that we think that there are maybe another 4 million or more species of insect that we haven't even named yet. And it's really quite sad, but there's no doubt at all that species are going extinct before we've discovered them. But there are insects that we do know have gone extinct. So for example, there was the world's biggest earwig which probably doesn't appeal to many people, but it lived on the island of St. Helena in the Atlantic and it's gone forever. There's a bumblebee Franklin's Bumblebee, which used to live in California and Oregon and it's extinct. That's it for Franklin's Bumblebee. So some have gone but most haven't, and it's not too late for those, you know, we could bring them back.
SS: But how do you actually know that they're definitely extinct? We’ve heard this before that this or that species, not only insects, in general, are extinct and then 10, 20, 30 years on, we see them come back.
DG: Yeah, it's a very good question. And, of course, it's almost impossible to prove beyond any doubt that something has gone extinct. Particularly when it's small, you know, we're pretty sure the dinosaurs are extinct, because it would be hard to miss one. But if it's a bee or an earwig, or a little wasp or something, then it's it is difficult to be certain there isn't one hiding somewhere, which is why not that many insects have yet been declared formally extinct because while doubt remains they aren't declared extinct. But so for example, Franklin's Bumblebee, there hasn't been seen there for 15 years, and every year people have gone to all the places where it used to be found and searched for it, and nobody can find it. It is possible, I'd have to admit, that there might be some hiding somewhere in the Rocky Mountains of North America where they haven't yet been rediscovered. So yeah, if we're really lucky, there might be a few left but as I say, I think the really critical issue is not whether or not individual species have gone extinct, but it's this broad collapse in numbers of insects that's really critical.
SS: So when we talk about pollinators of plants, such as different types of bees, like you mentioned, that especially are endangered at this moment, why them? What is happening? Are we having less flowers?
DG: Yes. The modern world doesn't have many flowers, particularly the way farming has changed with bigger and bigger fields, heavy mechanisation, large monocultures of crops grown with lots of herbicides used so there aren't any weeds, which means there are very few flowers in the landscape. And when there are flowers, they're often contaminated with insecticides, with pesticides designed to be poisonous to insects. So it's probably habitat loss due to intensive farming is the biggest driver of bee declines. But also, climate change is starting to kick in, and particularly with bumblebees, which are my kind of speciality, the big furry bees that are common in the Northern Hemisphere. They're really well adapted to living in cool places like Great Britain and lots of Russia and they don't like warm weather. So they're really beginning to be pushed northwards by the effects of climate change.
SS: Why are farmers so keen on using pesticides, if it actually hurts pollinators, and therefore their livelihoods?
DG: Yeah, it's a difficult one, and I have a lot of sympathy for farmers. So you know, we shouldn't forget that we absolutely need farmers because we'd all starve to death without them. And we need to somehow find a way of growing food and feeding everybody which is sustainable, which isn't doing ever-increasing damage to the environment. And as I think one of the biggest challenges that humanity faces is working out how to do that. So farmers use pesticides because they're worried that they'll lose their crop if they don't. And often, they're working on very small margins, they struggle to make a living and they can't afford their crop to be damaged by insect pests. So in the short term, they use them because they feel they have to, but the danger is that in the long term, you know, we're undermining the very kind of basis, the environmental health, which crop production depends upon. So in the long term, those farmers will suffer because their crops won't be pollinated. But they're more worried about getting this year's harvest in understandably because they need to make a living. So we need to help them basically.
SS: Right. I mean, all of us can actually stop using pesticides in our own gardens, but will an individual effort like yours and mine even make any difference if pesticides and chemicals are still being used on an industrial level? How is it possible to give up this gigantic nature of our food production, I mean, especially in the context of cost and population growth?
DG: Well, so there's two interesting things there. The first is I do think it would make a difference if individual homeowners, gardeners stopped using pesticides. I don't know the figures for Russia but in the UK, there are about 22 million private gardens that cover an area of about 400,000 hectares of land, which is actually a bigger area than all the nature reserves in the United Kingdom. So, you know, just imagine that all those gardens were pesticide-free and were full of bee-friendly flowers, that would actually make a really substantial difference. But it probably wouldn't overcome all of the problems because a much bigger area of land is farmed than is gardened. So we do need to come back to this question of how do we feed the world in a way that's truly sustainable? And I do think there are that it's not impossible, you know, we're clever creatures, if we put our mind to it, we can do this. And actually, I think part of the answer is to invest more in research and development into alternatives to pesticides. You know, there's a lot of money poured into developing new pesticides, millions of pounds dollars a year, go into research to find new pesticides, hardly any goes into research into ways to minimise pesticide use because the big companies make their money from selling the pesticides, not from not using pesticides. But that's where government needs to step in, I think and fund research into more sustainable farming methods.
SS: In China, I heard, farmers have started to pollinate their orchards by hand. Can this be the future of agriculture, I mean, everywhere in the world if China can do it?
DG: Well, yeah, no, I think it's pretty terrifying actually. You're right, in southwest China, there are big areas of apple and pear orchards, which are now all hand-pollinated. But in China, labour is very cheap, compared to most of the rest of the world. And it's a relatively high-value crop. It's really hard to see farmers in the developed world being able to afford to pay people to walk around their fields hand-pollinating every flower. And it would certainly be incredibly expensive, and it would mean massive increases in the price of food. And it seems kind of nuts to spend all that money on employing people to do what bees do really well for free. It will be much cheaper, I think, to look after the bees than to try and do their job for them.
SS: You know, there's this famous episode of Black Mirror, I don't know if you've seen it –
SS: – where robotic bees are being used in the UK because all real bees actually died. I mean, it's kind of sci-fi, okay, but companies are already looking into that possibility. Do you think that will be our last resort?
DG: I really hope not. And you're absolutely right. Yeah, there are robotics engineers around the world, I know of at least four labs that are building robot bees right now. But it seems kind of nuts, because that's going to be expensive, it's going to require lots of resources, metals, plastics, energy, they're going to need repairing and replacing, they're going to break down and litter the countryside. And a worst-case scenario, you know, terrorists break into the bee bot control system and turn them against us or something. When you know, real bees, they're biodegradable, they're self-replicating, they're carbon neutral. They've been pollinating flowers for more than 100 million years, and they're really good at it. It seems to me that looking after the real thing would be much cheaper than building their replacements.
SS: So climate change has a precarious toll on flora and fauna everywhere on the planet. We know for instance, how it causes ice to melt and prolongs Arctic summer and send polar bears in starvation. What impact does climate change have on insects?
DG: It depends on the insect. And actually, I mean, broadly, many insects like warmth, their thermophilic, they bask to warm themselves up. So you'd think on the face of it that actually, it might be quite good for many insects to have warmer weather. But the reality is that it doesn't seem to be the case that most insects that have been studied in this respect, even ones that like warm weather, like butterflies, are actually declining as a result of climate change. And it's partly because, we think, the habitats that they live in are now very fragmented so lots of creatures live on little nature reserves, little islands of habitat surrounded by a sea of intensive farmland or cities, roads, all sorts of manmade things, places where they can't live. So historically, when the climate changed gradually as ice ages came and went, insects ranges shifted towards the poles. And they could do that because they could move for there was a continuous habitat for them to move slowly northwards. But now if they've got to move northwards, they may have to jump hundreds of kilometers to find the next bit of suitable habitat. And many insects just aren't capable of doing that. So they're stranded on a little island, which is becoming too hot for them, and they can't get to the next place where they could theoretically live. So all the evidence we have is that basically climate change is adding to our poor insects’ woes.
SS: Is there any hope actually that bees, bumblebees, insects, in particular, bumblebees will adapt to mounting changes? I'm talking about resisting pesticides, heat waves, for instance.
DG: Yeah, certainly insects can evolve resistance to pesticides. But it takes time. And I think the problem that insects have is we're kind of bombarding them with lots of different problems all at the same time. They might be able to cope with one pesticide, if we kept using the same pesticide, eventually, they'd probably become resistant to it. But actually, you know, in the European Union, for example, we currently use about 500 different pesticides, and they change all the time. So there's little chance of the bees having time to evolve resistance to them before they switch to something else. And it's not just the pesticides, they're also having to cope with the climate changing, with loss of their habitat, with invasive species moving in, all sorts of other issues, which makes it really hard for them to keep up. So, sure, things can adapt over time, but it takes thousands of years. And we're not giving them anything like that.
SS: You know, while pollinators are endangered, climate change is causing some insects abnormal activity: growing temperatures increase pests’ metabolism, and you know, they're more hungry, their irruptions on crops are becoming even more ravaging. Climate change cannot be turned around, that's for sure. But is there anything that can be done about this particular problem?
DG: I think the simple answer is we have to try and minimise all of these other pressures that we're putting on insects. You're absolutely right, we're not going to stop climate change from happening, but we can reduce the severity of it by acting soon and decisively. And that's really, really important not just, of course, for insects, but for many other reasons, too. But in the meantime, if we provide bees, for example, with somewhere to live, and with lots of flowers, and we stop poisoning them, they might be able to cope with climate change, if they've got lots to eat, and everything else is looking rosy. They're not going to be able to cope with climate change if we keep poisoning them and destroying their homes.
SS: Just wondering, is it possible to exterminate a selected insect species without actually harming others?
DG: Yeah, well, it might be one day, it isn't at the moment. But there has been research done onto things called gene drives, which – I'm not a geneticist and I can't explain the mechanism exactly, – but essentially, you insert a gene that makes an insect sterile, which spreads through the population. And theoretically, you can release some of your genetically engineered insects into the wild, and it wipes out their entire species. And in lab experiments, this has been done with one species of mosquitoes successfully. And so it does offer the potential that in the future, we might be able to say, you know, “Here's a species, we've decided we don't want it anymore, we're going to wipe it out.” But that, I must admit, terrifies me because that is a kind of power that, you know, we're playing God on a global scale. It would be really hard to police, apart from anything else, because, you know, if one country or one laboratory releases these genetically engineered creatures, they're not going to stop at the national boundaries, they'll spread everywhere. And so, you know, where would we stop? Which species would we decide we didn't want and who would decide which those species were? It's a pretty scary world.
SS: Habitats for bees are disappearing not only because of pesticide use but also because our growing population needs new places to live, right? While we can try to help the situation, we can't really just stop encroaching on fields and meadows, can we?
DG: No, we can't. We obviously need places to live. But we can live alongside these and other insects, they can live in our gardens. As we discussed earlier, my garden is full of life. I mean, I'm lucky, I've got quite a big garden, but I'm looking out of the window behind my laptop right now. And there are butterflies flying around and bumblebees. If everyone's garden was like that, then it wouldn't really be a problem if urban areas expanded because wildlife would be living with us. So I think that is part of the solution, is persuading people to invite life in. Many people because they don't really like insects, they don't want them in their gardens. But if we could win them over, persuade them to love insects, which is kind of my mission in life, then maybe they'd realise how beautiful and interesting these creatures are. And they would welcome them into their gardens.
SS: But I mean, it’s not that I don't like insects, it’s just that there's some insects that I would want extinct – malaria mosquitoes and such, what do I need them for? I definitely won't cry if they disappear.
DG: Now, unfortunately, the insects we don't like, tend to be ones that would be extremely difficult to get rid of, even if we wanted to, and they are ones that are thriving in the modern world, things like horse-flies, mosquitoes, cockroaches, they're really tough and adaptable. So there's a kind of irony that the insects we would really like to do without are doing just fine. And the ones we really need and that we value as being beautiful or important as pollinators are the ones that are disappearing. Which is, yeah, unfortunate.
SS: Oh, you know, that's how good and evil works in the world. There's 95% of good, but the 5% of evil is just so well organised, you know?
DG: Yeah, something like that.
SS: So growing more insect attractions in gardens is one thing you advocate very strongly. Can personal garden-tending really become a trend so powerful that it actually overturns the current insect extermination process?
DG: It would really help. Certainly, some insects could survive just in gardens and actually, I have no idea what it's like in Russia, but in the UK, there is a real movement to do this. There are lots of people filling their gardens with bee-friendly flowers right now. You look on social media, everyone's talking about it, posting pictures of their gardens full of flowers, and bees and long grass, and so on. So there is a social movement taking off, and I've seen signs of it in other countries too. So that would really help. But as I say, the impacts of farming are bigger on a global scale. And there are lots of insects that won't be able to survive just in gardens alone. So we do need to tackle the issue of global food production. But as I said earlier, I don't think that's impossible. I mean, actually, the current intensive farming system is really inefficient. We produce very crudely, three times as much food as we need to feed everybody on the planet right now. But then we waste roughly a third of that food. And we feed another third of it to livestock, which is just a really inefficient way of feeding people. So if we could be more efficient, reduce food waste, and persuade everyone to eat less meat, then actually, we could greatly reduce the amount of farmland and we could set aside much more land for wildlife.
SS: Dave, thanks a lot for this wonderful insight to the world of insects. Thank you so much. It's been such a pleasure and very interesting talking to you. I'm inspired to do gardening after this interview. So I hope this talk will inspire anyone else who sees and hears it.
DG: I hope so. Thank you.
SS: Thank you. Bye-bye.