Will cockroaches really inherit the Earth?

Large cockroaches live under Price Hall of Virginia Tech University. Built in stone more than a century ago, this five-storey gray building houses the school's entomology department, whose faculty studies the insects that bloom in our forests, our farms and, often, our homes. Sometimes these reddish-brown American cockroaches – the largest species of cockroaches in the United States – will leave their underground homes, crawl into the old canals of the structure and infiltrate Price Hall, said Dini Miller, an urban entomologist at the 'university.

"I'm a little happy about this," she added.

Miller has devoted his academic career to the flat, six-legged and often abhorred insect pests, developing a keen understanding of why cockroaches have proved so resilient in our modern world, a world in which many species inspect – but certainly not all – eviscerated by pesticides and the destruction of their habitats. Moths, manure beetles, wasps, bees and dragonflies have all recently been the focus of a well-deserved public relations campaign. The New York Times Magazine, predict the environmental disaster if we should destroy the base of the planet's food web.

Recognizing that many inspected species could continue to decline in the 21st century – a time when extinction rates are about 1,000 times higher than expected natural levels – I asked Miller if the stubborn and robust cockroach could really inherit the Earth if other species were biting the dust. The answer is not simple, but it depends largely on the continued success of the human race: the seven or so species of cockroaches we call pests, the ones we consider indestructible, have learned to thrive in our human society. This means that they will continue to prosper, as long as we do it.

"They are with us forever"

"If it were not for us, they would not be booming," said Tim Kring, head of the entomology department at Virginia Tech. "But some species flourished because we gave them beautiful homes, food and water."

"So we are with them forever," said Miller, who paused and corrected himself.

"Say it like this: they are with us forever."

The indestructible cockroaches

Cockroaches have crossed the oceans to infest the United States. The worst pest of cockroaches, however, is not the American cockroach, which probably took place aboard African ships bound for the New World in the 1600s. It's the German cockroach, which can come from Europe or Africa. It's a smaller brown cockroach less than an inch.

Although German cockroaches are numerous in the United States, there are no wild German cockroaches living outside the country. Instead, they became domesticated critters. They all live with us.

"[German roaches] are those who have evolved to live with humans, "said Miller. They have gone from caves to our agricultural societies, exploring the world on board ships and aircraft. They come to accompany us all the way. "

Unlike German cockroaches, large cockroaches – such as the American cockroach or the steaming brown roaches of the south – do not rely entirely on our heat and our food to survive, though they are commonly found in large buildings, in especially in cities. Like cockroaches that take a look into the former Price Hall, these cockroaches thrive in modern human civilization. They do not always need to live in the dark recesses of our homes and restaurants, but rather reside in the sewers and on the outside. However, larger roaches do not have any problem getting in when they are hungry, thirsty or cold. "They can just move on when times are tough," said Miller.

And it is at this moment that all roaches cause sensation, whether they are German, American or others. "People are panicked by them," Santangelo said.

Even if their swarming brown bodies can cause disgust, their dependence on us could explain why they do not carry disease. They need us to stay healthy, alive and breeding, which makes them well adapted to infest our cities.

"They do not want to hurt our people," said Kring. "In a way, they cultivate us by not transmitting disease," he meditated.

Nevertheless, we certainly tried to annihilate them, using insecticides to trigger a large-scale national war against any cockroach that comes in.

But cockroaches resisted. "They are counteracting the countermeasures we are deploying," said Rick Santangelo, a cockroach control research specialist at North Carolina State University.

"They thwart the countermeasures we deploy"

Our chemicals could eliminate 99 roaches out of 100, but the remaining percentage will remain resilient. Then they will breed. "The more you are exposed to something, the more tolerant you become," Santangelo said. This does not mean that resilient creatures can not be exterminated from your home. With the right poisons strategically placed – like placing baits at hundreds of places around a kitchen – roaching inhabitants can be eliminated. But it's just your house.

"You can get rid of it in one structure, but we will not be able to eliminate cockroaches," Santangelo said.

Cockroaches, especially Germans, have another powerful weapon: their genes. For millions of years, German cockroaches have unintentionally developed an exceptional ability to resist poisons and malicious pathogens. In a study conducted in 2018, researchers discovered that German cockroaches had developed specific parts of their genome responsible for "detoxification", "defense against pathogens" and other related functions, thus allowing insects to grow in unclean and inhospitable places such as sewers. . It should be noted that American and German cockroaches have a genome that provides their body with a rich arsenal of a protein called P450, which neutralizes toxins and can respond to a wide variety of chemical threats.

"In a sense, they cultivate us"

"All of this gives them an advantage in an unhygienic environment," said Erich Bornberg-Bauer, professor of molecular evolution and computer genomics at the University of Münster.

"If they survive too, the Third World War is not proven and we would prefer not to know it," added Bornberg-Bauer, co-author of the Roach Genetics Study.

Until death we separate

Cockroaches and humans are in the long haul together. They do not seem to care, but why can not we get along with our six-legged roommates?

"It's shame," Miller said. "People are very ashamed when it comes to insects at home."

"They can not hurt you, they are just heinous," she added.

But the intimate cockroach-human relationship, though assured for almost eternity, is not exactly harmless.

Image: Shutterstock / Chattaphan Sakulthong

Although cockroaches can not carry Lyme disease, such as ticks, or inject us with venom that produces horrific lesions, such as the recluse brown spider, their poo can become a serious problem during a dreadful infestation. "All your plates, curtains and walls are covered with cockroach droppings," Miller said, noting that the problem was ubiquitous in the poorest neighborhoods of poor neighborhoods, but often overlooked by other socio-economic demographics. The cockroach poop picks up air and becomes an allergen, triggering wheezing, coughing and asthma.

It should be noted that most roach species are not unsightly pests. Many are beautifully colored insects, unrecognizable in feared roaches. They are like the billions of insects in a world plagued by habitat destruction, pesticides and a disrupted global climate. Many bugs simply have no more house. "Where there was a forest, there is now a cornfield," Kring said.

"I think there will be cockroaches"

Although the discomfort associated with insect decline can sometimes be misinterpreted or sensational, the inevitable reality is that many insect populations have actually declined significantly, but these freefalling numbers have not been seen everywhere. In some places, such as European protected forests, biologists have observed a drop of more than 75% in flying insect species in less than three decades. Meanwhile, scientists have not yet found declining numbers in other non-flying flea species. "I'm not saying it does not happen, I just do not see it in my own data," said Peter Dunn, a biologist at the University of Wisconsin-Milwaukee, who has been monitoring flying insects for decades. .

The future of wild bugs is, however, much more uncertain than the roaches that populate humanity, because our homes are often safe and full of food. It's a great place to live, especially if a disaster strikes the wild insects of the Earth, if a complete and terrible environmental failure occurs.

"I think there will be roaches," Dunn remembers.