Cockroach: Object of Disgust

This essay is part of a new Sydney Review of Books essay series devoted to nature writing titled the New Nature. We’ve asked critics, essayists, poets, artists and scholars to reflect on nature in the twenty-first century and to grapple with the literary conventions of writing nature. Read the other essays in the New Nature series here.

In some parts of Russia and Finland, a superstition once prevailed in the homes of the wealthy that cockroaches must be allowed to roam indoors and breed. To attract good fortune, newlyweds brought roaches into their houses. It was bad luck to kill the insect, especially by tossing it into a fire. About the same time, during the nineteenth century, in the American state of Maryland, it was believed that illness or death would follow if a cockroach flew into you. Another bad omen: seeing a roach crawl across the threshold of a room.

The cockroach possessed unusual powers, once; it was considered useful to humans. Pliny the Elder claimed the insect cured boils and scrofula and excessive itching. For the treatment of earaches, he recommended a mixture of rose oil and roach entrails — a remedy first documented by the Greek physician Dioscorides. Even in the seventeenth century, the cockroach still appeared as an ingredient in European ear medicines. An early nineteenth-century naval surgeon, William Webster, claimed an infusion of roaches worked as an anti-spasmodic. He also kept a strong tincture for the treatment of tetanus: cockroaches were then plentiful aboard the ships of the British navy (the Bounty, for example, was infested). In 1725, the naturalist Hans Sloane wrote that Jamaican children with intestinal worms took cockroach as a vermifuge. Among the final applications of the insect is its use as an expellant: a 1907 encyclopaedia for American pharmacists, Merck’s Index, lists cockroach powder as a diuretic and, mixed with oil, as a decoction for warts and ulcers. But by the middle of the twentieth century, the field of entomology regarded the therapeutic use of cockroach to be highly questionable, either a superstition or a popular fallacy, and to be relegated to the folklore of medicine.

Mitchell's Diurnal Cockroach

Mitchell’s Diurnal Cockroach, Polyzosteria mitchelli. Photo: Jean and Fred

Entomologists have identified about four thousand species of cockroach; some 450 of these are native to Australia. The insect is prolific and varied and, in several cases, beautifully coloured. The Mitchell’s cockroach, found in the Australian bush, is bronze and yellow and pale blue. Its excellent colours fade when it dies. Certain desert species are hairy. The Madagascar roach produces a hissing sound by expelling air through an opening in its abdominal segment. But the panorama drastically narrows in cities. The urban domiciliary cockroach comprises only a handful of species, none of which are native to Australia, and all of which are considered pests. More than a pest: no creature remains as abject a figure as the cockroach.

The Carboniferous is the name given to the geologic period between 360–299 million years ago in which coal beds began to be formed. The fossil story of the period also records roachoid insects of about the same size as the largest species that exist today: another name for the Carboniferous is the Age of Cockroaches. In these fossils, however, later entomologists identified the early forms of other taxa, and while the Carboniferous insects possess body plans that do resemble extant cockroaches, the lineage of today’s roaches properly commences some time in the Mesozoic era, a period that begins 250 million years before the present. The roach co-existed with the Tyrannosaurus rex, the Triceratops, the Stegosaurus. Some entomologists assume the early groups were diurnal, unlike the domiciliary species found in modern cities, which are active chiefly at night. Many Paleozoic cockroaches could fly. Because they could fly, they could navigate prehistoric swamps. Because their bodies were thin, they could squeeze into narrow cracks where they might avoid predators and survive environmental hazards. They are built to scale any surface, even sheer ones. Young cockroaches can regenerate lost antennae and limbs. They can eat almost anything, including their own moulted shells, and dead animals, living plants, excreta, fingernails, wallpaper, boxes, envelopes. It can eat the glue on envelopes. When the cockroach loses a food source—and this is one reason why it survives extinction events—it adapts its diet to whatever is available. The cockroach is ancient, tenacious, dependent.

American entomologists Louis M. Roth and Edwin R. Willis—important figures in the study of cockroaches—have proposed the theory that the domiciliary species have lived in the cave dwellings and other habitats of humans since the Paleolithic era, subsisting on our food and waste products:

From such primitive beginnings, domiciliary cockroaches have spread into every kind of structure that man has since devised. Yet despite the apparent predilection of certain species of cockroaches for man, man is only incidental to these associations. Only the shelter and food that man unwittingly provides for these unwelcome guests attract cockroaches to him; man’s physical presence is unnecessary.

Cockroaches find their way into restaurants, hotels, hospitals, factories, sewers, and become pests. They can find shelter in boxes of breakfast cereal and electrical switch boxes, in pantries and behind refrigerators. They even like coffee and will crawl into open bags of beans, where they are warm. Domiciliary cockroaches smuggle themselves onto ships, which is how they spread to many of the world’s cities: stowaways, they crawl across riggings and planks to the docks. In the 1920s, the Japanese Navy instituted a reward system for sailors who captured cockroaches; at the time the navy’s warships were infested with B. Germanica, the German cockroach, which remains one of the most common urban pests. Japanese sailors who collected a total of 300 cockroaches, either in a bottle or bag, were granted one extra day of shore leave.

In Sydney, the four most common domiciliary cockroaches are the German cockroach, the American, the Oriental, and the Australian. The German is an amber colour; its shell looks shrunken and wrinkly, like scratched varnish. The American is the largest of the pest species; their shell is reddish-brown, like wet rust. The waxy shell of the Australian cockroach is a darker brown; this species can fly. The Oriental roach is black and gleams. All four kinds are misleadingly named, and are thought to originate in the tropics or sub-tropics of Africa—the question of origin is a matter of disagreement among entomologists, since the domiciliary cockroaches have been widely distributed for centuries. In Sydney the cockroach flourishes in high humidity and heat: when the weather is unpleasant they seem to be everywhere, rushing forth like mercury. Everyone in Sydney has some story: the roach on the toothbrush, under the showerhead, inside the snorkel. In large, dense cities with cold winters, such as New York, cockroaches stay inside for many months of the year, scrounging in heated kitchens and consuming water in the traps of drains. They drink the condensation on flush tanks and pipes. When summer arrives in a cold city, the cockroach might then move to a new building and multiply.

Is any creature more despised? Why do we hate the cockroach? Tanya Latty, an entomologist at the University of Sydney, tells me that we tend to associate the cockroach with decay, and a human disgust response can be triggered by things we associate with death or decay or rot. ‘This is probably useful in an evolutionary sense — you don’t want to be somewhere there’s lots of cockroaches because there’s probably lots of decay. In places like Australia, where there are cockroaches around anyway, it causes a misplaced disgust. And it’s also the way they move. They’re so fast and erratic and large that it’s hard to watch them scuttle around. You see big cockroaches running around a radically new house, and that freaks people out.’

The pest species have long been associated with the transmission of disease: they’re followers of human activity, implicated in our problems. In the pharmacopeia On Medical Materials (written between 50-70AD), Dioscorides claimed cockroaches were ‘carriers of many diseases’. For centuries since, the insect has been considered a vector. Strictly speaking, the roach does pose a risk. But the question, Latty says, is how big a risk? In some cases, cockroaches can trigger asthma attacks. In terms of disease they function mainly as mechanical vectors. Latty says: ‘Cockroaches eat everything, and they might be nibbling on a rotten piece of meat or a pile of feces somewhere and they get their feet or mouths in it, and next they run across the lettuce you’re about to eat in your salad. They might transfer pathogens from the rotting food. The thing is: how often does that happen in a person’s house?’

Part of our disgust may derive from the fact that the cockroach is largely beyond our control: we cannot choose whether we share our homes with these things. They represent an outside world that at any time can intrude on our domestic space; they represent the ugliness that we live alongside but try to keep hidden. We attempt to eliminate them, but the results are temporary. When humans develop a new pesticide, the cockroach responds—and this response make take generations—by developing a resistance to the poison. More recently, Latty says, domiciliary cockroaches have ignored sugary baits, and the reason is thought to be a new aversion to sugary food. Roaches like sweet things—the domiciliary species have been known to imbibe dried milk from the mouths of sleeping babies. Now threatened by their attraction to sugar, the cockroach has changed its palate rather than going through the biochemical work of detoxifying the poison.

It’s part of their myth, part of their power, like a claim on humanity: we’ll never be rid of the cockroach. In 1958, scientists at the US Army’s Research and Engineering Centre in Massachusetts irradiated American cockroaches in order to study the insect’s level of resistance. The belief that cockroaches are impervious to radiation has its origins in the bombing of Hiroshima and Nagasaki. After the atom bomb attacks there were reports that domiciliary cockroaches had survived and were living amid the rubble. The American scientists placed the test insects into several polyethylene bags, large enough for about 20 roaches, and carried by conveyor belt to electron accelerator, where they were irradiated at various doses.

It’s a popular fallacy that roaches can withstand extremely high levels of radiation. Humans will die after exposure to about 1000rad (radiation absorbed dose). The scientists at the US army laboratory in Massachusetts found that American cockroaches are rendered sterile at 1000rad and die at 10,000rad. Later experiments put the lethal cockroach dose at 6400rad, a level of tolerance that does not compare to the constitution of the Habrobracon wasp, which can survive exposure of up to 180,000rad. Wasps, not roaches, might inherit an irradiated Earth, if the world’s last insect can somehow find a suitable source of food.

Literature presents the cockroach as a figure of pity. In Federico García Lorca’s play, The Butterfly’s Evil Spell, a roach falls in love with an injured butterfly, who leaves him when she regains her ability to fly. The cockroach is doomed, untouchable, unworthy of affection. In Kafka’s Metamorphosis, Gregor Samsa is rejected by his horrified family. Before the transformation, he worked as a travelling salesman to service a family debt and support his younger sister and parents (his father is feckless, his mother unwell). Then one morning—the story almost goes without glossing—the good son wakes up ‘transformed in his bed into a monstrous insect’. Overnight his life is foreshortened; his bed has become a kind of deathbed. But what kind of insect is Gregor? Vladimir Nabokov, in Lectures on Literature, notes that commentators have described insect-Gregor as a cockroach, which ‘does not make sense’, because Gregor has short legs and a ‘rounded back suggestive of wing cases’, which would conceal little wings that allow for ‘miles and miles in blundering flight’. Gregor is changed into a winged beetle, Nabokov claims, but the young salesman ‘never found out that he had wings.’ This detail is significant: ‘Some Gregors, some Joes and Janes, do not know that they have wings.’

Wanting to leave the matter a mystery, Kafka never specifies the type of insect into which Gregor is transformed. Some translators have rendered the original ungeheueres Ungeziefer as ‘monstrous vermin’ and ‘gigantic insect’ or ‘large verminous insect’. A few months before the publication of The Metamorphosis, Kafka wrote to his editor about the illustration for the story’s title page: ‘The insect itself cannot be depicted. It cannot even be shown from a distance.’ Probably Kafka hoped that readers would have in mind our own monstrous insect, that we’d complicate the story with our own dislike or phobia for an unlovely pest that turns up in our home. Kafka himself was afraid of mice. ‘The night is theirs,’ he wrote to his friend Max Brod.

Some readers imagine Gregor as a cockroach: no other domiciliary insect with hard shell, antennae, and thin legs so suitably fits the picture of abjection. The critic, poet, and translator Michael Hofmann is responsible for the only English version of The Metamorphosis (Penguin, 2008) to specify that Gregor is a cockroach. I ask Hofmann why he made this decision. He says the credit should go to a friend, the German writer Durs Grunbein, who said ‘I hope you’re not going to call him an insect.’

‘Which of course I was,’ says Hofmann. ‘Even though I’d always been dissatisfied with “insect” and “monstrous insect” and the completely unusable “vermin”. The bagatellizing “bug”, quite impossible. The German is ungeheueres Ungeziefer—two categorical negatives. This is something unspeakable. It’s not a euphemism or a bit of entomological musing. Not something you can make up for with an adjective, like “monstrous” or “hideous” or “jolly nasty” or ‘thoroughly repulsive”. Hence “cockroach”. Disgusting. The worst. Absolute nightmare.’

He says Grunbein reminded him that people can read ‘insect’ versions of Kafka until The Metamorphosis comes out their ears. The existence of these other versions gave Hofmann the liberty to call the object of disgust by its—as many readers feel—true name. German has a word for cockroach (Kakerlake), but Hofmann says Kafka couldn’t have used it because Kakerlake sounds a little comic, and it’s too close to K’s own name. ‘I think of my version as the Florida edition of Kafka,’ says Hofmann, who lives in Gainesville. ‘Because Florida, no less than Sydney, boasts splendid cockroaches.’

The cockroach isn’t all monstrosity. The insect possesses appealing qualities, beyond its durability across segments of the geologic timescale. It’s not commonly recognised, say Tanya Latty, that the giant burrowing cockroach, a native Queensland species, displays extensive maternal care. (There is a Neapolitan saying: ‘Every cockroach is beautiful to its mother.’). The giant burrowing cockroach is about 8cm long, and at 30g is among the heaviest species in the world. Also known as a litter bug, the mother gives birth to live young and looks after them for nine months, sometimes longer, in a subterranean nest structure. In the nest there will usually be an adult male and female. Latty keeps one as a pet: ‘They’re very, very cute and they’re kind of slow. They eat dried gum leaves and they not the kind you ever see inside a house. They live for up to 10 years, and the one I have is almost six years old. It’s nice to have a long-lived insect pet. You don’t normally get so long out of insects.’

Rita Francis put enormous faith in psychic power after a spiritualist medium predicted the date of her first husband’s death. A popular Sydney psychic, Marguerite Young, revealed to Rita the day (not the month) of her husband’s fatal stroke. Or rather, the death was foretold by a Syrian spirit guide whom Marguerite claimed she could contact in the afterlife. Rita, a pensioner, lived in Dulwich Hill. She attended the Newtown Congregational Church, and her friends were spiritualists. This story takes place in a part of Sydney where the degree of human-cockroach co-habitation is high.

While on holiday in Brisbane, two years after the death prediction bore out, Marguerite had a sudden vision: cockroaches running out of a man’s slippers into Rita’s shoes. Marguerite asked her spirit guide in the afterlife what the vision meant, and she was told the vision meant Rita would marry again. Evidently, the cockroaches were significant: she would marry someone with the surname ‘Roach’. In Sydney, Marguerite relayed the new information, the strange vision, and as it happened, Rita did know someone called Roach: a 71-year-old pensioner named Ernest Roche. Until hearing of the vision, Rita had never thought of marrying Ernest—even so, she had a high regard for him. Marguerite had more information from afterlife: Rita would be married on the tenth. Again, the exact month was uncertain. In light of this prediction, Rita and Ernest began to court. They announced their engagement. They were married in Newtown on 10 February, 1950. The cockroach has already played myriad roles in human history, usually as a villain: some people turn the insect into a love charm.

‘It’s just too wonderful!’ Rita told a reporter from the afternoon tabloid The Sun, which ran the news of a wedding between ‘two elderly spiritualists’ on page three. The Sun reporter, perhaps deliberately, misspelled the groom’s homonymic surname as ‘Roach’.


Adele Marie Barker and Bruce Grant, The Russia Reader: History, Culture, Politics, 2010.
William J. Bell, Louis M. Roth, Christine A. Nalepa, Cockroaches: ecology, behaviour, and natural history, 2007.
A.N. Caudell, An Economic Consideration of Orthoptera Directly Affecting Man, 1919.
H.M. Gordin, ed., Merck’s 1907 index: an encyclopaedia for the chemist, pharmacist and physician.
Franz Kafka, The Metamorphosis and Other Stories, Translator: Michael Hofmann, 2008.
Franz Kafka, Letters to Friends, Family, and Editors, Translators: Richard and Clara Winston, 2013.
Federico Garcia Lorca, Plays, Translator: Gwynne Edwards, 1990.
Louis M. Roth and Edwin R. Willis, The Reproduction of Cockroaches, 1952.
Louis M. Roth and Edwin R. Willis, The Medical and Veterinary Importance of Cockroaches, 1957.
Louis M. Roth and Edwin R. Willis, The Biotic Associations of Cockroaches, 1960.
Richard Schweid, The Cockroach Papers, 1999.
Staff writers, ‘Cockroach ‘vision’ led to marriage, The Sun, 10 February, 1950.
W.H.B Webster, Narrative of a Voyage to the Southern Atlantic Ocean, in the Years 1828-30, 1834.
R. A. Wharton and Martha L. Wharton, ‘The Effect of Radiation on the Longevity of the Cockroach, Periplaneta americana, as Affected by Dose, Age, Sex and Food Intake’, Radiation Research, No. 11, 1959