Casy Shanks, of Balclutha Primary School, asks :-

Are insects important?

John Marris, an entomologist who is curator of the Entomology Research Museum at Lincoln University, responded.

At first glance it might seem that insects aren’t that important. We could all get by without having the honey that the bees kindly provide for our breakfast toast. And most of us would welcome a world without pesky houseflies in summer or the misery of sand fly bites and wasp stings. But dig a little deeper and it is very clear that insects are a hugely important part of the world’s ecosystem. In fact, it is doubtful that without insects we could continue to exist. The truth is that insects are far more important to us than we are to them. Insects could go on about their business quite happily without humans, whereas we would probably not last long at all without our six-legged friends. Certainly, the Earth would change dramatically in their absence.

One obvious and important role played by insects is as pollinators – not just honeybees, but all sorts of insects, including bees, wasps, moths, flies and beetles. A large proportion of the world’s crops rely on insects for pollination, without which we would struggle to feed the world. In financial terms, insects provide many billions of dollars worth of pollination services, completely free of charge. If insects were to disappear from the planet many of the world’s flowering plants, which are dependent on insect pollination for their reproduction, would ultimately go extinct.

Less obvious, but equally important, is the expert help that insects provide in recycling nutrients. A vast array of insects play a vital role in breaking down and decomposing organic matter. These include scarab beetles feeding on animal dung, flies feeding on carrion, wood boring beetles turning logs into sawdust, and many others. Insects play other vital roles, including as predators and parasites that help to maintain the balance of life. Insects themselves are food for many species, which couldn’t live without them.

The renowned entomologist, E. O. Wilson, painted a picture of a world without insects and their relatives in which he predicted the breaking down of many of the complex systems that keep life on Earth in balance. Ultimately he saw that within a few decades the world would return to the state it was in one billion years ago, composed mainly of bacteria, algae and very simple plants.

Based on that scenario, we can definitely consider the insects to be not just important, but essential for life as we know it.