Entomologist Dino Martins, known for his work on pollinators, has turned his attention to nature's most maligned creatures in his latest book, Hidden Creatures: Luscious Leeches, Bashful Botflies and the Wondrous, History-Shaping World of Parasites. The book, published this month, argues that parasites play vital roles in ecosystems and human health, challenging their reputation as villains.
Early fascination with insects
Martins grew up in western Kenya with foster parents Joe and Sarah Ellen, surrounded by the rich biodiversity of Mt Elgon, Kakamega forest, and Kerio valley. Without television, he turned to observing creatures around him, particularly insects. 'We had no television, so I learned to look at the creatures around me. Insects were the easiest to find,' he says. This early obsession with 'dudus' (Swahili for insects) led to a scientific career focusing on pollinators, butterflies, and now parasites.
Parasites as ecosystem indicators
According to the Royal Entomological Society, there are an estimated 1.4 billion insects for every person on Earth, comprising up to 90% of all animal species. Martins notes, 'Throughout our lives, we are never more than a couple of feet from an insect, yet we ignore them.' He argues that parasites are essential to healthy ecosystems: 'No ecosystem or habitat exists without parasites. Their presence is an indicator of a healthy, complex biodiversity.'
Personal encounters with parasites
Martins recounts a childhood experience raising caterpillars, one of which was parasitised by wasps. The wasps laid eggs inside the living caterpillar, which developed and eventually burst through its skin to form cocoons. 'This made such an impression on me as a young child,' he says. The book is based on his encounters with parasites in East Africa, New York, Borneo rainforests, and London parks.
Human health and parasite evolution
Martins writes that one in three people host parasitic nematodes at any given time, including hookworms 'that have sex frequently and vigorously' in our intestines. He suggests that some parasite exposure may strengthen immunity, despite modern obsessions with sterilisation. 'Parasites do cause a lot of harm and suffering... however, some scientists are starting to think of parasites as just one part of our microbiome,' he says. He warns that human efforts to eradicate hookworms have been futile due to natural selection, and that vaccines will face similar evolutionary pressures, leading to a 'long-term arms race between humans and hookworms.'
Broader implications for biodiversity
Martins argues that parasites are central to understanding biodiversity and extinction. When species like the dodo go extinct, we lose insights into complex relationships and potential lessons for medicine. 'Some day we may need the lessons from these parasites to survive greater challenges or emerging pathogens,' he says. He also highlights how global dietary shifts, such as fish farming and crowded livestock conditions, create opportunities for parasite spread and antibiotic resistance.
Conservation and human responsibility
Martins, chair of the insect committee of Nature Kenya and a research professor at Stony Brook University, emphasises that humans do not have the right to oversee the extinction of other species. He asks, 'Are we creating conditions where host-switching might become more common? This has ramifications for our own health and that of endangered species.' His book aims to interest nature enthusiasts, conservationists, biologists, and medical students exploring the link between ecosystems and health.
Hidden Creatures is published by William Collins in London on 30 July and by Knopf in New York. Martins, a 2015 Whitley gold award winner, concludes: 'I try to present the natural history of the parasites as it is. Even the most disgusting have some of the most incredible adaptations and abilities.'
