The world's insect population is in decline — and that's bad news for humans

A bee is in Berlin, Germany. Bee populations are declining in industrialized nations.

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Climate change, habitat loss and pesticides are threatening insect populations. 40% of all insects are declining and a third of them are in danger according to a report in 2019.

Oliver Milman, an environmental writer, says that human beings would be in big trouble without insects. insects play a critical role in pollinating plants, breaking down waste in forest soil and forming the base of a food chain that other, larger animals rely upon.

It would be an extremely dire place to live in, and certainly not something we should ever aim for. There would be rotting feces and corpses everywhere because dung beetles and other insects that break down those materials would be gone.

In his new book, The Insect Crisis: The Fall of Tiny Empires That Run the World, Milman charts the decline of insects. The monarch butterfly population in North America has plummeted in the past 40 years, for instance, and the overall trends are not good.

He says that the world would be duller without insects. There is a decline in most insect populations and that spells trouble for them but also for us.

Interview highlights

What does the loss of pollinators mean?

There are places in China where the loss of insects is so great that armies of people have been told to fan out and pollinate crops by hand. The insects have done these jobs for millions of years.

There is a growing concern about food security, especially when you think about what is happening with the overall trends. The world's population is growing. There has been. In the last 50 years, the volume of agricultural production has increased by 300%. At a time when we are demanding more and more pollination, we are losing pollinators. There are more mouths to feed. We need more land. We need more farmland. We are losing the pollinators that help us.

There are insects that serve as pollinators.

When it comes to pollination, bees get a lot of the attention, but there are a lot of other insects that do the work. Three-quarters of the world's flowering plants and a third of the world's food crops depend on pollinators. It is not just bees. There are a lot of flies. The cocoa crop is pollinated by the midges. There are also insects. The major pollinators are the swastikas. Another insect that is disliked but important for our environment.

Without these creatures, we wouldn't have apples, cranberries, melons, almonds, broccoli, blueberries, cherries, and so on. We would not have ice cream because it is Pollinated by insects. We would be without many of the luxuries of our lives. Curries would become a historical dish because there wouldn't be any spices. Without insects, many spices would be stripped from our diet. When we think about pollinator declines, it is important to remember that many of the world's poor agriculture rely on pollination that is directly pollinated in their immediate surroundings, and without that, all of the nutrition is stripped from them. The U.N. has warned that this is going to become a food security issue, something that the world needs to focus on quite acutely.

The insects at the base of the food chain are important.

When you remove insects from the base of the food chain, everything starts to fall apart. They are crucial for the basic foundations of forests and grassland. We think about the placement of soil as a way of cycling nitrogen through the soil to ensure that plants grow.

We don't like mosquitoes, but they provide a lot of food to birds and frog. When you start climbing up the food chain, you affect things that we do value. Bird numbers have been reported to be down in several countries, and the birds that eat insects are faring worse than the birds that are omnivorous, such as crows. They are an important base to the food pyramid, and they are a very important part of our environment.

There are some things that insects can do.

I like the idea of the caterpillar generating their own antifreeze to ward off the cold. It seems like an incredible ability to me. There is a water beetle that can escape from the back of the frog, if it is eaten. When you think about insects objectively, they are very impressive. After being beheaded, cockroaches can last two weeks. They can run fast. They can survive a lot of radiation and poison.

The ability of bees to organize socially is just incredible. honeybees can add and subtract numbers. Researchers have found that bumblebees can play soccer. They can learn to play soccer with food and bees can detect mines. There are so many amazing things that they can do with their minds. The more you learn about insects, the more you discover how amazing they are.

On insect habitat loss.

The idea of the Amazon rainforest being burned down or chopped down is something we think about when we think about habitat loss. A lot of the habitat loss is mundane. It is the conversion of a barren piece of land into a Starbucks. It is the conversion of a field where wildflowers will grow into a field of soy or corn. It is mostly driven by agriculture. Some of it is driven by sprawl. The laying down of highways, heavy industry and so on. The model that has exploded in Europe and North America is being transported elsewhere. Other countries are using this method of farming large fields of single crops with chemicals in order to boost their yields. A lot of what we consider unproductive grounds, messy land, the kind of stuff the place is filled with wildflowers, with scrub, with kind of brambles and weeds, we call them weeds when they are really important food providers for insects.

Lauren Krenzel andSeth Kelley edited the interview. They adapted it for the web.