Thursday, January 28, 2021

So you want to kill a cockroach?

I have done it so many times at night and in total darkness.

No, I don’t mean that, silly!
I mean quietly getting into the kitchen and quickly turning on the light to view the cockroach, in all its spleandour, and with all its relatives covering every inch of my kitchen floor.

As quickly as the light goes on, they vanish and disappear through any opening or crevice they can find; under the pots, plates and pans. Once that happens, you won’t find even one of them. Getting away from imminent danger is only one of their most amazing feats of survival.

As you know by now, killing or getting rid of cockroaches in the home or outside is no easy matter.

Ask the fumigators and exterminators and they will, if they want to be honest, tell you that it is not an easy task. They will, however, take your money and try.

So you want to kill cockroaches? Do you know what you are up against?

The cockroach will survive for several days without its head and, if kept from developing any mould, it can last headless for a month.

They are more resistant to radiation and scientists say if there is a world nuclear war, the cockroach is the only known creature that will survive it.

And it does not even have lungs!
In their book, Medical and Veterinary Entomology, 2002, (p.32), Gary Mullen and Lance Durden say that cockroaches are among the hardiest insects on the planet, with some species capable of remaining active for a month without food, or being able to survive on limited resources like the glue from the back of postage stamps.

“Cockroaches can hold their breath for 45 minutes and can slow down their heart rate.”

With six legs and eighteen knees, cockroaches don’t die that easily even if you crush them twice! But, without water, they can die of thirst in a week.

Nature.com says that female cockroaches mate once and are pregnant for the rest of their lives.

It goes on to say that cockroaches usually reproduce sexually. “But in times of crisis when males are scarce, females can reproduce by a process known as ‘parthenogenesis’. Thus, they can produce offspring – all female – with no help from males.

Roaches can run at speeds of nearly 3km/hr and can make up to 25 body turns in a second – the highest known rate in the animal kingdom. And, being nocturnal, they do most of this in the dark.

You still want to kill a roach?
The cockroach is most hated because of its unhygienic habits and survival skills.

Mike Potter, Extension Entomologist at the University of Kentucky College of Agriculture, says cockroaches are the most common insect pests infesting homes, food service establishments and other structures. “Cockroaches are repulsive and objectionable to most people simply by their presence. They are also capable of mechanically transmitting disease organisms such as the bacteria, which cause food poisoning. Recently, cockroaches have been found to be an important source of allergy in people, second only to house dust.”

A cockroach is a beetle-like scavenging insect with long antennae and legs. The Amateur Entomologists’ Society says there are nearly 4,000 species of cockroaches (Dictyoptera, Blattodea) in the world, of which only 25 to 30 have any pest status, and claims that some of the rest make great pets.

Wikipedia says cockroaches (or simply “roaches”) are insects of the order Blattodea. This name derives from the Latin word for “cockroach”, blatta.

“Among the most well-known species are the American cockroach, which is about 30 mm long, the German cockroach, about 15 mm long, the Asian cockroach, also about 15 mm in length, and the Oriental cockroach, about 25 mm.”

Tropical cockroaches are often much bigger.

Cockroaches are generally considered pests; however, it is believed that only about 30 species (less than 1%) infest urban habitats.

“Cockroaches typically become established in homes after being introduced in grocery bags, with laundry or, in some cases, wandering in from outdoors,” says Potter. “Once cockroaches become established they are prolific breeders capable of producing several thousand offspring in a year.”
Potter says cockroaches prefer to live where there is food, warmth and moisture.

“Since cockroaches flourish where food and moisture are readily available, sanitation is an important step in prevention and control,” said Potter. “Empty soft drink bottles, cardboard boxes and paper bags should not be allowed to accumulate. Food containers should be sealed and any crumbs or spillage cleaned up.”

“Cockroaches are considered one of the most successful groups of animals,” says Steven Jacobs, senior extension associate in Entomology in Penn State’s College of Agricultural Sciences.

“Because they are so adaptable, cockroaches have adjusted to living with humans much more readily than humans have adjusted to living with them.”
Cockroaches thrive in nearly every corner of the globe, despite our best attempts to eliminate them.

Once, repulsed by the sheer arrogance and fearlessness of a big brown pregnant roach, I let go off a wild back hand with a rolled up newspaper decapitating it and sending the head and the torso in different directions. I lost a cup and a saucer in that assault. I was, however, humbled to see the headless body crawling under a cardboard box flap and, a little while later, dutifully laying its eggs before wondering away as if it had its head screwed on the right way.
That is because cockroaches, like all insects, breathe through a system of tubes called tracheae.

“The tracheae of insects are attached to the spiracles, excluding the head,” says Wikipedia. “Thus, all insects, including cockroaches, can breathe without a head.”

So decapitation as a means to control roaches will not get you any relief.
It is almost impossible to squash a cockroach before it shoots out of sight behind the refrigerator, suitcase or something in the home but it is often quite easy to zap it with the nozzle of a vacuum cleaner.

The explanation, Dr Hananel Davidowitz of the NEC Research Institute in Princeton, New Jersey, says, is that the jet-propelled bug thinks with its behind.

”The cockroach,” he says, “is able to sense minute changes in the air flowing round its body using tiny hairs on two posterior appendages called “cerci”ÔÇöand that includes your foot coming down. Signals from those hairs feed into a group of 14 vital nerve cells which process the information. The result: now you see it, now you don’t!”

ABC News says the vacuum cleaner, however, has even smart roaches fooled.
“If a vacuum cleaner approaches from behind a cockroach, the wind goes from its head to the nozzle. It thinks the attack is from the front and it turns round and runs straight into the nozzle,” their research scientist says.

Cockroaches have also developed interesting ways of ensuring that their young make it to adulthood. Most species give birth to live young ÔÇö highly unusual for insects ÔÇö but a sure way to prevent other critters from feeding on their eggs.

And if food is scarce, adolescent cockroaches can live on a very reliable resource ÔÇö their parents’ feces.

Even if you cut off its head, a cockroach would still run around the house for about a week and lay its eggs before dying of thirst because its brain is not in its head; it’s scattered throughout its body. The cockroach’s heart is nothing but a simple tube with valves that pump blood back and forth. The heart can even stop without causing harm to the insect.

Interestingly, roaches wear their skeletons outside their bodies and they bleed white blood.

So the next time someone calls you an insect, ask them to be a bit more specific. It’s a compliment to be called a cockroach. Think of the unequalled resilience! Besides, cockroaches will “inherit the earth” should humanity extinguish itself by nuclear war.
Wouldn’t you like to be the only one there with all those roaches?

SOURCES: Internet, Wikipedia, Essortment, BBC, ABC News,

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