Who’s the Pest? brings the insect world into close focus

Source: Getty

Time for crunch: fried grasshoppers are a popular midday snack in Thailand

Who’s the Pest?
Wellcome Collection
London 18 April-16 May

Insects outnumber us 200 million to one. They are embedded in our everyday lives whether we like (or realise) it or not, from the hundreds of insects that share our home and the thousands that share our garden to the butterflies that inspire beautiful designs on our clothes.

Insects have evolved with us and helped to shape our planet. They pollinate our crops and break down our waste. They produce honey used in medical dressings and clean infected wounds. They help to control other insect pests and are even an important source of food for millions of people worldwide. It would, in fact, take the extinction of only a few species to cause entire ecosystems to collapse, and our life as we know it would cease to exist. But if humans were to become extinct, insects would barely bat a metaphorical eyelid.

Last month’s Alien Nation season on BBC Four explored the wonder of insects and the secrets of their success. The celebration continues in the Who’s the Pest? season beginning later this month at the Wellcome Collection, in collaboration with the cultural organisation Pestival: a swarm of activities bringing together designers, chefs, food scientists, entomologists, bug enthusiasts and bug destroyers.

You may be wondering why chefs and food scientists are so interested in insects. Insects au Gratin (23 April-5 May), an installation created by “speculative designer” Susana Soares in collaboration with Steak Studio, will make the case for entomophagy, or eating insects, as a solution to the food challenges we face. Its focus includes innovative techniques for harvesting insects and 3D printing them directly into meals. Meanwhile, Exploring the Deliciousness of Insects (30 April and 1 May) promises “evenings of canapés and discussion”, with Nordic Food Lab chef Benedict Reade conjuring “comestible creations that make the inedible edible”.

Although the practice is not entirely socially acceptable in the UK, there are good reasons why insects are already eaten in 80 per cent of the world’s nations. They are literally little bags of protein. Their incredible bodies are highly accomplished at turning plant matter into protein. Dung beetles, by weight, contain more protein than beef and apparently just four grasshoppers provide as much calcium as a glass of milk.

Were we to farm insects, scientists believe, fewer greenhouse gases would be emitted. And because insects have a high food conversion rate, they would need just a quarter of the intake of sheep, and around half that of pigs, to produce the equivalent amount of protein.

As nutritious as this all sounds, you may well share my aversion to the idea of chomping on cockroach legs for lunch. The workshops will give insect-eating enthusiasts a chance to try to convince us otherwise.

Protein aside, when you peel back the layers of an insect you uncover a remarkable hidden world of natural engineering - an intricate and beautifully designed living machine that, to my mind, surpasses any human invention. As I discovered when working on the BBC Four documentary Insect Dissection: How Insects Work, insects are truly the Transformers of the natural world, with bolt-on body parts that allow them to survive in some of the world’s most extreme environments. We are now learning to use these ingenious designs to our own advantage.

We have all stepped on an insect. Even the white mush that sticks to your shoe has a function. It is called the fat body and is a sort of energy storage system. The crunch they make is the insect’s cuticle breaking - and it is one of the toughest, most lightweight and versatile materials found in nature. Researchers have spent years trying to replicate it, and have recently developed a low-cost and biodegradable material called “shrilk”, which could one day replace plastics.

In some ways, insect bodies are remarkably similar to our own. They may have six legs and carry their skeleton on the outside, from which they hang their muscles, but they also have a mouth, an oesophagus, an entire digestive system, a brain and even a heart. But many of their organs look strange and the ways in which they function can be very alien.

For example, insects do not have blood that carries oxygen around the body. Instead they have nutrient-rich haemolymph. This is moved around by their heart, a long tube that runs the length of their body. Rather than acting as a pump, it works like a squeezy bottle of water in the bath.

Although insects naturally need oxygen to survive, they don’t breathe air through their mouth and nose into a set of lungs. Instead they have holes along the side of their body called spiracles that allow air to enter into an intricate network of tubes extending out like branches around the internal organs and feeding them directly with oxygen. This works well for a small creature, but the passive nature of this breathing system is quite limiting. In fact, the lack of a complex oxygen distribution system is one reason why insects remain so small.

Insects don’t use noses for their remarkably sophisticated sense of smell, but instead deploy the long antennae on their heads (sometimes as long as their whole bodies). The level at which they can detect the tiniest amount of chemicals - and we are talking individual molecules - is truly mind- blowing. Even the most advanced piece of kit in my laboratory comes nowhere near this astonishing sensitivity.

But this ingenious natural engineering is also their downfall. The more we understand about insects’ sense of smell, the more we can adapt this to our own ends. By connecting microelectrodes to the antennae of insects in my lab, we can pick out the chemical signals they rely on in their everyday lives and this we can exploit.

We have recently developed natural repellents based on odours from people who rarely get bitten by mosquitoes, and pheromones to attract bedbugs into traps. Bees can sniff out explosives and drugs much better than any sniffer dog. Mosquitoes are now being studied to see whether they can detect the “smell” of malaria.

Could an insect’s incredible sense of smell really lead to new and exciting non-invasive diagnostics? Although it sounds hard to believe, scientists are now working on systems that use live bees in airports to detect drugs. Perhaps more realistically, insects can help us to construct man-made devices to do these things more efficiently.

All this research and more will be revealed as part of “The Secret Insects of Bloomsbury”, a walking tour that I am leading (18, 19 and 20 April).

You wouldn’t think that central London would be host to an abundance of insects and their secrets, but thanks to many years of ground-breaking research at the London School of Hygiene and Tropical Medicine, these critters are quite literally underfoot. Just 1 metre beneath the footpath of Gower Street and Malet Street lies a buzzing metropolis - home to tens of thousands of foreign mosquitoes that represent those wreaking havoc around the globe. The tiny, long, narrow vaults and domed ceilings of the insectaries hold vast numbers of buzzing, hungry tropical insects, some of them responsible for carrying the most dangerous parasites on the planet. And it’s not just mosquitoes; these tunnels are literally lined with bedbugs, house dust mites, triatomine bugs, sandflies and house flies. All, of course, are kept safely in containers from which they cannot escape.

It’s unlikely that everyone will love insects as much as I do, but next time you are about to squish one under your heavy boot, take a moment to think about their role in your life.