Influential Insects: let us count the ways

July 5th, 2024

Insects may be small, but they're little changemakers. Just take Erica McAlister's word for it.

A profile shot of author and scientist Erica McAlister holding up an insect specimen.

You may not be aware of it, but insects have a wide-reaching influence in our world. From helping to solve crimes, to being a food source, and even acting as inspiration for new technologies.

Erica McAlister, entomologist and co-author of Metamorphosis, takes us through all the fascinating ways that insects are changing our world.

Insects in food and agriculture

Have you been lucky enough to see one of the largest moths in the world – the Giant Wood Moth Endoxyla cinereus – found across Australia? To be fair, most haven’t. What about its close cousin Endoxyla leucomochloa? Maybe you haven’t seen the adult, but you would have heard of the caterpillar, known as the witchetty grub. You may have even eaten it.

We have been eating insects for millennia but it is only recently that we have thought about it in terms of food security. Try persuading the average person to eat a giant cooked grub (which can be quite tasty, think prawn with satay sauce), and most would coil up resembling the startled grub itself. But eating insects is now being entertained on a truly global scale. It is larvae of a fly – a maggot, specifically the larval of the black soldier fly (Hermatia illucens) – that is the delicious morsel being reared at an industrial scale (just to make you feel even more uncomfortable).

An extreme close up photo of a black soldier fly on a wooden surface.

Could the larvae of the black soldier fly be the answer to food insecurity? (Photo: oktavianus mulyadi/Unsplash)

Insects helping with crime solving

Australia is home to what is colloquially called a body farm – the Australian Facility for Taphonomic Experimental Research (AFTER). This is the only such facility in the southern hemisphere where forensic research uses donated human remains to enable much needed research on entomological succession on cadavers.

By studying flies and other insects we are able to work out a timeline to help in criminal investigations, timelines that may be influenced by multiple factors such as weather, clothing, and narcotics to name a few.

Insects in medicine

Debridement therapy is not a new thing in Australia. The Ngemba people of New South Wales are some of the earliest humans to record cleaning wounds with maggots. This may seem counter-intuitive but, thanks to some species’ liking of dying and dead flesh, they have a place in modern medicine. Further to the debridement, they also disinfect the wound and stimulate greater wound healing.

Maggots can actively inhibit some of the nastier pathogens that are picked up in hospital including MRSA, and as such act as miniature nurses caring night and day for the patient.

A top down view of thousands of maggots.

Close up of Black soldier fly (BSF) larvae or maggot, Hermetia Illucens insect farms for fish and poultry feed

There’s more to maggots than meets the eye. (Photo: JakaSuryanta/Adobe Stock)

Insects in manufacturing

Within CSIRO there is a group looking at silk produced by Hymenopterans – bees, wasps and ants – and the group has designed new products such as sponges and films based on this research. Dr Tara Sutherland and her team are studying how naturally occurring proteins such as silks can be mimicked and modified for commercial applications.

Not only are everyday products such as sponges and fibres are being generated, but new research is leading them to develop smaller and smaller products such as chemical sensors.

An extreme close up photo of a honey bee on a wooden surface.

Honey bees and the silk they produce are inspiring researchers to innovate. (Photo: Kai Wenzel/Unsplash)

Insects in technology

The meat ant Iridomyrmex purpureus – endemic to Australia – creates large oval-shaped nests of between one and two metres in diameter that may contain nearly a million individuals (although more often it is in the tens of thousands).

These ants all have to communicate with each other and navigate to and from the nests. Researchers are now looking at this species, often considered a pest, to help us learn more about developing navigations systems for driverless cars!

 

Copy of 'Metamorphosis', with a variety of insects used to shape the letters in the word 'Metamorphosis', resting against the base of a gum tree and surrounded by tanbark.

Metamorphosis by Erica McAlister and Adrian Washbourne.

Whether it’s the astonishing properties of resilin, the protein that makes fleas jump; the proboscis of the mosquito’s mouth being used to develop smart needles; or the computational dynamics gleaned from studying locust swarms in Africa – in Metamorphosis, Erica McAlister and Adrian Washbourne reveal the wonder of insects, the historical figures who have made great breakthroughs in understanding them, and the increasingly vital role they play in ensuring life, as we know it, continues.

Metamorphosis is inspired by the BBC Radio 4 series ‘Metamorphosis’ [external link].

Metamorphosis is available online and from all good bookstores.

 

About the authors

Erica McAlister is Curator of Diptera at the Natural History Museum, London. She is the author of the acclaimed books The Secret Life of Flies and The Inside Out of Flies.

Adrian Washbourne is an award-winning producer for BBC Radio 4.