Steven Spielberg missed a bet with his movie, Jurassic Park. He focused on the age of dinosaurs. If he really wanted to freak people out, he’d focus on a much earlier era, the Carboniferous Period: a.k.a. “The Age of Cockroaches.”
Yes, cockroaches, those scuttling, light-fearing pests we’ve all encountered at one time or another, were once the predominant insect on the planet, and if their place in the evolutionary hierarchy has slipped a little, it shouldn’t be taken as evidence that they are lacking in survival traits: they’ve hardly changed in the 320 million years since they first appeared on the planet. That’s a pretty good indication that their design continues to be effective.
Today, there are at least 3500 known species of cockroaches, of which only 25 (less than one percent) are really well known to most people, having achieved the dubious distinction of household pests. (A good move on their part; most cockroaches live in very specific habitats, such as the splash zone of waterfalls or in bat caves, but by linking up with humans–travelling with them on ships, wagons, trucks and airplanes–the pestiferous species of cockroaches have spread all over the world, from the North Pole to the South.)
The most common pests, and therefore the most common cockroaches, are the American (Periplanta americana), German (Blatella germanica), Oriental (Blatta orientalis), brown-banded (Supella supellectilium), and Madiera (Leucophaea madera). The worst pest of all these pests is the German cockroach, which is responsible for the majority of cockroach problems in North America.
Despite coming in so many different species, all cockroaches do share a few characteristics. They’re flat, oval insects, though they vary in length by species from tiny (one millimetre) to horribly huge (nine centimetres) in length. Some have wings, some don’t, and even those with wings don’t always fly. Most cockroaches are nocturnal and shun the light, actively seeking to escape it (hence the unsettling sight of cockroaches scurrying for cover when you descend into your kitchen for a midnight snack). A new pest introduced into the U.S. in the 1980s promises to be even more annoying, however; the Asian cockroach can fly, and is actually attracted to artificial light, which means instead of running for cover, it buzzes light bulbs.
Cockroaches have extremely sensitive antennae and sensory bristles that enable them to detect tiny amounts of food and moisture. Those two long hairy things sticking up from the abdomen are called cerci: they’re able to sense very slight changes in air pressure. Within half a second, the cockroach scuttles away (at a speed of up to five kilometres an hour), which is why it’s almost impossible to sneak up on a cockroach.
Cockroaches are champion breeders, although it doesn’t sound like they take much joy in it: some species mate once, then the female remains pregnant for the rest of her life. (Which is why a single cockroach, if it happens to be a pregnant female, can quickly become a plague of cockroaches. One female German cockroach can produce 200,000 cockroaches in a single year.) In the case of the American cockroach, mating is initiated when the female releases a chemical odor, or pheromone. When the male senses the pheromone, he starts flapping his wings and backing into things–anything that happens to be handy. Eventually, more or less by chance, he backs into a female, and deposits a packet of sperm.
Females create egg cases, called ootheca, that can contain from 16 to 32 eggs, depending on the species. Some cockroaches quickly deposit the ootheca, hide it, then forget about it; others carry it around until the eggs are ready to hatch. In some species, there even seems to be an element of maternal care: the cockroach nymphs remain close to their mother for several days.
Cockroaches can eat almost anything, including paper, cigarettes, beer, dog food, fruit, grease, and each other, because they carry colonies of protozoa and bacteria in their gut that help break down their meals. In nature, because they’re so common, they play an important role in the rapid decomposition of forest litter and animal feces. They’re also food for many animals (including, sometimes, humans). (They benefit is in another way, too: apparently crushed cockroaches applied to a stinging wound help relieve the pain. Just thought you’d like to know.)
In our homes, however, we’re not happy to see them. No one has ever conclusively proven that they spread disease; however, considering that one way they often enter houses is by swimming through the sewer and like to feed on garbage, it seems likely. (Turn about being fair play, they also feed on us once in a while: in homes with heavy infestations, they’ve been known to feed on sleeping people by nibbling at sores, eyelashes, eyebrows and finger and toenails.) At the very least, they breed rapidly, soil things, and smell bad, which is reason enough to want them out of the house.
Alas, that’s harder than it sounds. Because they breed so rapidly, they quickly adapt to pesticides, and most of the pesticides that kill roaches are poisonous to humans and pets, too, which makes traditional extermination an unpleasant option. Traps have been developed that use cockroach pheronome as bait, but that’s not practical on a large scale. The traditional “roach motel” takes advantage of cockroach’s propensity to crawl into cracks and crevices; once inside, the roach is trapped in a sticky substance.
The best way to get rid of them is to deny them food and water–although that’s harder than it sounds, since a single spot of grease is a delicious meal to a roach. Still, carefully cleaning up all crumbs on a daily basis, washing dishes in hot, soapy water, keeping trash tightly covered and keeping pets’ food dishes off the floor can all help.
Unfortunately, roaches can live for a month without food (well, what do you expect? They can live for a week without a head and stopping their hearts doesn’t even kill them–they’re tough little bugg–um, bugs). They can only last a week without water, though, so eliminating dripping faucets, pouring Lysol into toilet bowls at night to make the water undrinkable and not overwatering house plants can help, too. (Pouring Lysol down drains nightly can also keep roaches from crawling up into your sinks. So can keeping sink plugs in place.)
Finally, put boric acid into nooks and crannies where cracks hide. Although safer than other pesticides, it’s still not safe for pets or humans to breathe or come in contact with, so you have to be careful; but it’s effective against roaches because it’s both poisonous and abrasive. Abrasiveness is important because it scratches the waxy cuticle that covers roaches, and losing that covering makes roaches subject to deyhdration.
Difficult to kill, ubiquitous, and enough to give strong men the willies: I’m telling you, Steve, it’s a natural: Carboniferous Park: The Return of the Roaches.
Has a nice ring to it, doesn’t it?