Bengaluru: On May 15, India’s Chief Justice Surya Kant likened a section of the country’s youth to “cockroaches”.“There are already parasites of society who attack the system and you want to join hands with them? There are youngsters like cockroaches, who don’t get any employment and don’t have any place in profession. Some of them become media, some of them become social media, some of them become RTI activists, some of them become other activists, and they start attacking everyone…and you people file contempt petitions,” he said, commenting on the genuineness of the law degrees of some advocates who had approached the Supreme Court over senior designations. His comment drew instant criticism, and continues to do so, despite his ‘clarification’ a day later saying that the media had “misquoted” him. But, your honour, cockroaches are important insects. They may be pests in houses but they come there because of how we keep our spaces: garbage-filled and messy. In nature, where most of these insects are found, they play a crucial role in nutrient cycling in ecosystems. Nature’s ‘cleaning crew’Cockroaches – those six-legged, red-brown insects scurrying around in our kitchens at night – are the stuff of nightmares for many. The insects can successfully evade persistent murder attempts, even take wing if they need to. Cockroach phobia has a name: katsaridaphobia. But only around 30 cockroach species are associated with humans and considered household pests. Of these, four species – the German, American, Australian and Oriental cockroaches – are the most common. All the remaining 4,500-odd species of cockroaches recorded so far across the world are not pests. They occur across diverse natural systems: grasslands, deserts, rainforests, even in volcanic craters. Regardless of where they occur, their function is the same: cleaning up.“Cockroaches are scavengers,” said entomologist V. Shubhalaxmi. “They eat rotting material, leaves, food, anything. They’re part of the cleaning crew in nature.”In houses, they come for leftover food scraps.In the wild, cockroaches break down dead leaves, wood and other organic matter. Though this process releases some carbon dioxide, it ultimately contributes to the formation of soil organic carbon – a crucial part of carbon sequestration. This is precisely what governments across the world are trying to hasten, spending billions to mitigate climate change. “They play a crucial role in nutrient cycling,” said entomologist Priyadarsanan Dharma Rajan, Senior Fellow at Bengaluru’s Ashoka Trust for Research in Ecology and the Environment (ATREE). “Cockroaches help clean up the system.”Nutrient cycling makes the world tick. It is the process by which nutrients and essential elements (such as carbon, nitrogen, and phosphorus) move between living organisms and their physical environment. Living with cockroachesIn fact, roaches are so efficient at breaking down organic matter that ‘blatticomposting’ – or using cockroaches to break down waste – is now a thing. Cockroaches, also called blattids because they belong to the insect order Blattodea (along with termites, their closest relatives), are voracious omnivores. They break down waste faster than worms (which are usually used for composting), and can adapt to a huge range of environmental conditions. This “emerging method” of using cockroaches for composting, “is being recognized as an environmentally friendly, cost-effective technology with resilience to harsh conditions”, a study in 2024 noted. According to some new research, blatticomposting may be an ideal way to deal with slaughterhouse waste.Forget organic matter, some roaches can even break down plastic. In 2024, scientists found that the Argentinian wood roach (Blaptica dubia) can biodegrade polystyrene plastics with “ultra-high efficiency”.Cockroaches are a problem only when they come in conflict with human beings, and enter homes, said Shubhalaxmi. But here’s the thing: they come by invitation. “This invitation is through the way we manage our waste, in the way we handle our dustbins and kitchens,” she told The Wire. And some elements of modern urban design such as the allocation of space for storing waste under the kitchen sink make it even more conducive for cockroaches because these wet, dark and warm spaces stocked with ample food in the dustbin are the perfect cockroach habitat, she added. Juvenile cockroaches can use the drainpipes linking to the same storage space to move across apartments in their search for food waste. “So essentially, we are punishing them for being themselves, doing their job of cleaning up,” Shubhalaxmi said.One effective way to not attract cockroaches to your house is to keep it clean: no open waste, no food scraps lying around, no piles of dry newspaper that cockroaches can use as convenient birthing and breeding spots, she added.Yes, roaches can be beautiful While our horror images of cockroaches are those donning shades of red, black, brown, roaches are extremely diverse. Some are striking. Like the neon-green Panchlora nivea or Green banana cockroach found in Cuba. Or the stunning blue-and-yellow Mardi Gras cockroach, a native of Australia. The Glowspot Roach (Lucihormetica subcincta) is bioluminescent: it glows in the dark. Others don shades that will put even eyeshadows to shame – like the Metallic Emerald cockroach (Pseudoglomeris magnifica) that is native to the forests of south China and Vietnam. India too is home to some stunners. Like the Indian domino roach (Therea petiveriana), a black-and-white polka-dotted beauty. You’ll find this cockroach only in leaf litter in the scrub forests of southern India. Therea regularis, or the Orange domino roach in scrub vegetation in Pondicherry, India. Photo: Seena Karimbumkara.Scientists have reported around 190 species of roaches in India, with some being endemic to specific mountain ranges and habitats. Tamil Nadu is home to the highest diversity of roaches, at 55 species. And we’re unearthing more. Last year, scientists at the Zoological Survey of India reported a genus of cockroaches for the first time in India, while describing two new species from Meghalaya. This genus, Anaplectoidea, was previously reported only from southeast Asia and China. In March this year, scientists at the ZSI discovered a new species of roach, Neoloboptera peninsularis, from farmlands just outside Pune in Maharashtra.An important food sourceHead to wild spaces anywhere in the country, and there, under the carpet of fallen leaves, you’ll find native roaches. And that’s why these are important prey for many ground-dwelling wildlife. “Frogs, reptiles, birds, and even other carnivorous insects like the praying mantis eat cockroaches,” Shubhalaxmi said. “Even centipedes are known to eat them.”In 2003, behavioral ecologists in Tamil Nadu observed the elusive gray slender loris – a small, nocturnal species of primate that is closely related to the lemurs of Madagascar – eating four species of roaches in the wild. Wildlife biologist Swapna Nelaballi observed another closely-related primate species, the slow loris, crunching on forest roaches in the forests of Tripura in 2008. Both species of lorises, listed under Schedule I, are afforded the highest protection under the Wild Life (Protection) Act 1972 in India.Cockroaches are also being hailed as a potential superfood for humans because of their high protein content. Many communities across the world already consume cockroaches as part of their diets. Dharma Rajan and his team have been studying the edible insects of the northeast and have found that local communities consume more than 300 insects. Their edible insect collection at ATREE, which this reporter visited on May 20, also contains several species of cockroaches. A collection of edible cockroaches from the northeast at ATREE’s Insect Lab in Bengaluru. Photo: Aathira Perinchery.They are fascinatingDid you know that some species of roaches are dedicated parents? The male and female Wood-burrowing cockroach (genus Cryptocercus) from North America live in a nest with around 20 of their children (cockroach juveniles are called nymphs) for three years or more. “The parents defend, extend and clean the gallery, feeding the young by regurgitating food (much like many birds do) and with specialised fluids produced by glands in their gut. The babies return the favour, spending almost 10% of their time grooming the adults,” according to David Yeates, Director of the Australian National Insect Collection, CSIRO, in The Conversation.Some Indian cockroaches may show these behaviours too – we just haven’t discovered them yet. Around 20 years ago, Dharma Rajan was in the forests of the Biligiri Rangaswamy Hills in Karnataka when he spotted a female cockroach on a wild banana species carrying something on its back. “They turned out to be babies,” Dharma Rajan recalled. He did not collect the roach because it was a mother (insects often have to be collected to identify them, or describe them as a new species).Some roaches, like bees, even pollinate flowers. A rare parasitic plant found in Japan, China, Taiwan, and Vietnam relies on a specific species of cockroach, Margattea satsumana, to pollinate it. There are records of native cockroaches also pollinating specific flowering plants in South America. Some roaches, like the Pacific beetle cockroach (Diploptera punctata) gives birth to live young — and produces milk for its babies. This milk is so rich that a study found it to have higher nutritional potential than conventional mammalian milk. Disgust factor aside, this cockroach milk has potential as a “new super food and important alternative to traditional mammalian milk that might become available for consumption in the near future”, a study noted in 2018.It may seem unlikely, but some people even keep roaches as pets. Because they are odourless and easy to maintain, a species found only in Telangana and Andhra Pradesh in India, the Question Mark cockroach (Therea olegrandjeani) is among the most popular pet roach species worldwide. “People even conduct cockroach races in the US,” commented Shubhalaxmi. Cockroach racing is popular in Australia too.A collection of edible cockroaches from the northeast at ATREE’s Insect Lab in Bengaluru. Photo: Aathira Perinchery.They are ancient, resilient Cockroaches are ancient creatures. Fossils show that some of the earliest cockroach ancestors walked with dinosaurs around 320 million years ago (the late Jurassic and Cretaceous periods). This means that they survived a meteor and the drastically altered environmental conditions that entirely wiped out dinosaurs and other creatures. Today, the only place you will not see cockroaches on the planet is Antarctica: it’s too cold for them, and there’s no permanent human habitation here. But you’ll find them even in homes in the Arctic because conducive environments, along with their ability to reproduce fast, is what helps invasive cockroach species like the American cockroach thrive. Ironically, we can even learn about human history through another invasive species, the German cockroach: scientists who studied the DNA of German cockroaches found that the insects’ genetic history may mirror trade routes across centuries. “We believe global trade facilitated this spread because more closely related populations are found in countries with cultural links, rather than countries that are simply close to one another,” wrote Theo Evans, Associate Professor of Applied Entomology at the University of Western Australia and Qian Tang, Research Associate in Evolutionary Biology, Harvard University.The German cockroach can in fact adapt so much that they have grown to even resist pesticides. According to one report, manufacturers created cockroach baits containing glucose (cockroaches love sweets) laced with pesticides in the 1980s. Thirteen years later, the cockroaches stopped opting for these sweets altogether: the mutant cockroaches had “reorganised” their sense of taste by changing their genetic make up. Clearly, these cockroaches are locked in a constant evolutionary arms race with humans. “This is why the term has shifted from pest control to pest management,” Shubhalaxmi said. “We can never win the war against these insects. We can only learn to coexist with them.”