Like A Fly on the Wall

I am a birder currently working in a botany research group. There is a certain circularity to these two aspects of my life, as it was put to me during my undergraduate degree that I couldn’t claim to know anything about birds if I knew nothing about plants; the two are so intricately linked that it is impossible to study either in isolation. Now, having read The Secret Life of Flies, I can see that I have no chance of understanding birds or plants until I know more about flies. Flies provide so many ecosystem services that without them, the natural world would cease to function. As the book’s author, Erica McAlister, puts it, “…how can you answer any questions about the habitat if you ignore one of the largest components of it?”

Image: CSIRO Publishing

Image: CSIRO Publishing

This book made me see how naïve I had been to the importance of flies. I have often taken photos of flowers being visited by hoverflies and a host of other dipterans without ever really thinking that they could provide pollination services on a scale that is vital for maintaining plant reproduction. Yet, from the pages of McAlister’s book, you will discover that “flies are more important pollinators than bees.” Similarly, while reading the ‘Detritivores’ chapter, I was struck with the realisation that the photos of swarms of flies I recently took on the beaches of Wilson’s Prom were not that unusual at all. Flies that feed on decaying kelp and seaweed are a common occurrence, from temperate beaches to tropical ones.

And that is what this entire book was like. It was packed with fact after interesting fact. In some ways though, the fast pace of the writing was to its detriment. As a novice fly-er, there was no chance that I was going to remember which family of flies with an unpronounceable name was the one that did this and which was the one that did that. However, once you come to terms with the fact that the nitty-gritty in the pages of this book is not what's important - rather, it's aimed at opening your eyes to the diversity of fly morphology and ecology - you will see that it's necessarily fast-paced to fit every topic in. In just 241 pages, McAlister provides an informative and accessible overview of this diverse group of invertebrates. The book is helpfully broken down into chapters that are largely focused on an individual feeding guild. This helps to limit the number of topics covered to a barely manageable subset. The enthusiasm with which McAlister writes hints at the fact that she could have produced reams more text in addition to what made it to the published pages.

Although I often see species of flies visiting flowers, I had never appreciated the scale of the pollination services that flies provide to plants until reading The Secret Life of Flies. Image: Rowan Mott

Although I often see species of flies visiting flowers, I had never appreciated the scale of the pollination services that flies provide to plants until reading The Secret Life of Flies. Image: Rowan Mott

Unbeknownst to me, flies are a common component of beach ecosystems around the world. Perhaps I should have guessed that from this spectacle I photographed in a beach cave at Wilsons Promontory National Park. Image: Rowan Mott

Unbeknownst to me, flies are a common component of beach ecosystems around the world. Perhaps I should have guessed that from this spectacle I photographed in a beach cave at Wilsons Promontory National Park. Image: Rowan Mott

The writing is made more engaging by McAlister revealing few truths about herself as well as the flies. The world’s chocolate production depends on pollination by flies, but disruption to this would be of little consequence to McAlister because she doesn’t like chocolate. Perhaps more bizarrely, McAlister reveals just how deep her love of flies really is while talking about the venation of the wings of fungus gnats. She states, “I find the looping created by the joining of the veins named M1 and M2 rather sensual and become quite syrupy when I look at them.” In addition to insights into her own personality, we are also shown glimpses of what it is to be a professional dipterist (a researcher studying flies). From lying fully clothed and covered with sand on an ocean beach while waving a net over piles of seaweed, to studying underlying genetic influences on alcoholism using vinegar flies (a globally important model organism for genetics research) in the laboratory, it is clear that dipterists’ careers can be as varied as the flies themselves. It would not surprise me if some people are inspired to become dipterists after having their interest piqued by this book, particularly when readers learn of McAlister’s past study locations in far-flung places, including the mountains of Peru, the beaches of the Caribbean, and London’s Kew Gardens.

Conversely, The Secret Life of Flies may turn some people off a career as a dipterist. At the very mention of flies, most of us immediately think of pesky gate-crashers at picnics and barbeques, or worse still the itch of a mosquito bite. McAlister acknowledges that flies earn “nothing more from us humans than feelings of disgust.” Although this book does much to dispel blatant negativity by highlighting the value of flies to our society and environments, it does not shy away from exposing the more disgusting aspects of their ecology. From typical blood-feeders that pierce a vein or slice skin to lap the pooling blood, to bot flies that develop in the nasal passages of camels, there are many occasions where a squeamish reader might want to skip forward a few pages. Yet, rather than frame these aspects negatively, McAlister celebrates the myriad ways that flies have evolved to exploit their environment, and the opportunities they present. This revelry will enable many readers to go beyond their normal comfort level and read on to keep learning.

Blood-sucking, as displayed by the blood-laden fly on this water skink’s head, is a familiar interaction many of us have had with flies. The many ecological roles of blood-feeding flies are explored in The Sanguivores chapter of The Secret Life of Flies. Image: Rowan Mott

Blood-sucking, as displayed by the blood-laden fly on this water skink’s head, is a familiar interaction many of us have had with flies. The many ecological roles of blood-feeding flies are explored in The Sanguivores chapter of The Secret Life of Flies. Image: Rowan Mott

I'm not sure if this book will fly off the shelves, but those who do pick up a copy will be rewarded with a fascinating journey through the world of a group far more important than most ever realise. The Secret Life of Flies will be an important gateway for people like myself, who know little of the importance of these insects, to discover more about this unique group. It seems that the more you scratch the surface, the more examples of weird, wonderful and environmentally important species you will find. The Secret Life of Flies fills an important gap for those wanting a light-hearted introduction to all things fly. 

You can purchase your copy of The Secret Life of Flies from CSIRO Publishing.


Rowan Mott

Rowan is a PhD student studying seabird ecology. When he's not thinking about the ocean, he likes to think about woodland birds. 

You can find him on Twitter at @roamingmoth


Banner image courtesy of Rowan Mott.