Renowned entomologist and evolutionary biologist Dino Martins demonstrates in his latest book that even the most gruesome creatures have vital roles to play in nature, as reported by The Guardian.
Martins spent his formative years in biodiversity-rich western Kenya with his foster parents, observing birds, flowers, and insects on Mt Elgon, Kakamega forest, and Kerio valley.
He was transfixed by the miniature world beneath his feet, which included dung beetles rolling cattle dung, safari ants migrating, male butterflies sucking nutrients from mud, and bees pollinating the critically endangered African violet.
"We had no television, so I learned to look at the creatures around me. Insects were the easiest to find," says Martins.
The Royal Entomological Society estimates there are 1.4 billion insects for every person on Earth, making up to 90% of all animal species and more than half of all living things.
"Throughout our lives, we are never more than a couple of feet from an insect, yet we ignore them," Martins says.
"From the food we eat to the ecosystems we depend on, insects and other invertebrates play essential roles, most of which we overlook or fail to appreciate."
His early obsession with insects morphed into a scientific calling focused on overlooked environmental architects.
Martins, who chairs the insect committee of Nature Kenya and is a research professor at Stony Brook University in New York, documented these bugs in books like Insects of East Africa, Butterflies of East Africa, and Our Friends the Pollinators: a Handbook of Pollinator Diversity and Conservation in East Africa.
For his latest book, Martins embarked on a journey to document the lives of much-maligned parasites, an idea encouraged and revived by British-Sierra Leonean writer Aminatta Forna.
The book, Hidden Creatures: Luscious Leeches, Bashful Botflies and the Wondrous, History-Shaping World of Parasites, published this month, is based on personal encounters in East Africa, New York, Borneo rainforests, and London parks.
Martins, who studied anthropology at Indiana University and earned a doctorate in biology at Harvard, recalled raising caterpillars as a child only to discover one had been parasitised by wasps.
The wasps laid eggs in the caterpillar's body, developed and fed on the living host, and emerged by bursting through its skin to form cocoons.
"This made such an impression on me as a young child," says Martins, who describes parasites with curiosity and empathy.
He notes that understanding ecosystems requires understanding the creatures holding them together.
"No ecosystem or habitat exists without parasites.
Their presence is an indicator of a healthy, complex biodiversity, even if we might be alarmed by their presence."
Martins argues that parasites are central to biodiversity and extinction, and their ability to move between hosts or hijack immune systems offers insights for novel medical therapies.
"Parasites are central to the story of biodiversity … affecting all living things directly or indirectly," he says.
When species like the dodo become extinct, humans lose the ability to understand complex relationships, and practical lessons in biology and conservation vanish alongside the disappearing parasites.
"Some day we may need the lessons from these parasites to survive greater challenges or emerging pathogens," he says.
"I strongly feel that we don't have a 'right' as one species to wilfully oversee the extinction of another.
Are we creating conditions where host-switching might become more common? This has ramifications for our own health and that of endangered species."
In Hidden Creatures, Martins writes that one in three people serve as unwitting hosts to parasitic nematodes at any given time, including hookworms.
He suggests exposure to parasites can strengthen immunity despite modern obsessions with sterilization, warning that completely removing these creatures can have unknown consequences.
"Parasites do cause a lot of harm and suffering and there is no question that our attempts to control them through the ages have saved many lives and livelihoods.
However, some scientists are starting to think of parasites as just one part of our microbiome which has many roles to play in all aspects of our health," he says.
Martins argues that global shifts in diets, such as fish-farming and crowded livestock conditions, have created opportunities for parasites to spread, leading to antibiotic resistance.
Human interventions remain subject to natural selection, meaning toxic chemicals will not eliminate all bugs.
"Some will survive and increase due to natural resistance, while using chemicals indiscriminately will end up making the problem worse," he says.
This explains why efforts to eradicate common hookworms using preventive drugs like albendazole fail to stop reinfection from contaminated soil.
While no approved vaccines are available for hookworms in humans, several candidates are in clinical trials, notably one developed by the Sabin Vaccine Institute.
Martins argues that vaccines will still face evolutionary processes, sustaining a long-term arms race between humans and hookworms.
The 2015 Whitley gold award winner hopes Hidden Creatures will interest nature societies and students of conservation, biology, and medicine.
"I try to present the natural history of the parasites as it is," he says. "Even the most disgusting have some of the most incredible adaptations and abilities."
