Cockroaches are more diverse, complex, and less contagious than we think
Cockroaches have plagued humans for thousands of years, and many of us are very familiar with at least one of the roughly 30 species of cockroaches that can make their home in our habitat.
However, there are more than 4,000 live cockroach species known to the scientific community, and they maintain a surprisingly diverse lineage, probably before dinosaurs. They are ancient and complex creatures that largely do not deserve the stigma associated with their names. Pest cockroaches make up less than 1% of all cockroach species, and while our disgust may not be unfounded, they are not as monolithic and scary as we think. In some cases, we can even learn something useful from them.
Here's a closer look at a few notable species, from worldwide pests, such as cockroaches in the United States and Germany, to a few of their lesser-known and lesser-known relatives.
American cockroach
Periplaneta americana is the largest pest cockroach species, averaging 1.5 inches in length. 1 It is also one of the fastest terrestrial animals relative to its size, capable of running 50 lengths per second. 2 Despite its name, the species originated in tropical Africa and was brought to North America by European settlers and slaves. It now lives all over the world.
The American cockroach is peridomesic, which means it lives near people both indoors and outdoors. Popular habitats include dark, damp places close to buildings, from cellars and sewers to trash cans and stakes. It is a common pest in restaurants and grocery stores, but less common in the home. Studies of cockroach behavior have shown that these cockroaches have personalities, and their speed, agility and toughness can inspire better rescue robots.
Australian cockroach
The Australian cockroach (Periplaneta austraasiae) is another large, living pest with a confusing name. It is thought to have evolved in Africa and then spread around the globe with the help of humans in recent centuries. Australia is one of the places where it invaded, but it is also prevalent in parts of the southeastern United States and in tropical and subtropical regions around the globe.
This species is often mistaken for the American cockroach, which is similar in appearance and behavior. However , the Australian cockroach is slightly smaller , with a pale yellow band on the upper margin of its forewings. They usually live outdoors, and their habitat ranges from bark and stakes to porches and greenhouses. Indoors, their shelters may include water pipes, sinks, toilets, and other places with enough heat, moisture, and darkness.
Brown band cockroach
The brown band cockroach (Supella longipalpa) is a small domestic cockroach, which means it spends its entire life indoors. It's a worldwide pest that may have evolved in Africa, but its global expansion seems to be more recent than many cockroaches: it was first reported in the United States in 1903 and probably didn't reach Europe until World War II.
Unlike the American cockroach, this species is more common in homes than in restaurants. It is more dispersed throughout the home than other cockroaches and usually lives far away from food and water. It is sometimes referred to as the "furniture cockroach" because people will find it in bedrooms, bookshelves, and other places where there is no food, or behind pictures on the wall. In addition to more traditional cockroach control methods, the brown band cockroach is susceptible to parasitic bees, The Microeti, which can parasitize in large numbers on their eggs enough to cause population collapse
Brown-headed cockroach
The brown-headed cockroach (Cryptocercus punctulatus) is a wild forest dweller from North America with different populations in the Appalachian Mountains and the Pacific Northwest. According to the University of Virginia's Mountain Lake Bio Station, it is the only wingless cockroach in its range, describing it as "impossible to mislead" another species. 6
Cryptocephalus may be the basic lineage of modern cockroaches, and these wood-eating animals are also seen as models of early termites, which evolved from cockroaches about 170 million years ago. 7
8 Brown-headed cockroaches are more closely related to termites than some other cockroaches and can reveal the evolution of termite nesting behavior. A 9 mating pair will take three years or more to raise a litter of nymphs capable of eating rotting wood thanks to the cellulose-digesting microbes passed down by their parents.
Cape Hill cockroach
The Cape Mountain Cockroach (Aptera fusca), also known as the Table Mountain Cockroach, is a large non-pest species native to the fynbos biome of the Western and Eastern Cape provinces of South Africa.
A. fusca does not lay eggs like most insects, it is oviparous, meaning that its eggs develop and hatch inside the mother's body and then give birth to cubs. The species makes a loud squeaking sound when startled, and for extra protection, it secretes a foul-smelling liquid that is reported to stain the skin for days.
Deadhead cockroach
The Dead Head Cockroach (Blaberus craniifer) is the largest cockroach in North America, growing up to 3 inches long. Its name refers to a distinctive facial-like marking on the dorsal plate of the anterior chest (the dorsal plate of the upper chest), similar to a black skull with a reddish feature on an amber background. The species is native to Mexico, Central America and the Caribbean, and has been introduced to Florida.
Deadhead cockroaches inhabit the forest floor in the wild and feed on fallen leaves and other organic matter. They are not common household pests, but some people do keep them as pets.
Domino cockroaches
Therea petiveriana is an unusual-looking cockroach native to the bush forests of southern India. Its small, rounded body is black with white spots, and this pattern is considered an example of defensive imitation. 11 In addition to resembling dominoes, this motif protects cockroaches by camouflaging them as a different local insect: the six-point ground beetle, an aggressive carnivore with defensive secretions that can make it a threat to predators.
Domino cockroaches also produce their own defensive secretions, but studies have shown that they are more about communication than deterrence, possibly acting as an alert pheromone that helps adult cockroaches warn each other of impending dangers.
Florida Forest Cockroach
The Florida Forest Cockroach (Eurycotis Floridana) is a large species native to the southeastern United States and is sometimes referred to as the "palm worm" (also used as a term for the American cockroach). It is a habitat for surrounding life, usually living outdoors, from tree stumps and shrubs to stakes and greenhouses. It occasionally enters the room, but has little incentive to stay: the species feeds on plants, lichens, mosses and soil microbes, does not like to eat human waste, and is barely threatened by the region's mild winters.
Adults can grow up to 1.6 inches long and 1 inch wide. They lack well-developed wings and move relatively slowly, even if disturbed. When frightened, adults can spray foul-smelling irritants from 3 feet away with some degree of directional control.
German cockroach
According to the University of Florida Institute of Food and Agricultural Sciences (IFAS), the German cockroach (German cockroach) is "the species that makes all other cockroaches bad." 13 Despite its name, it may have evolved in Asia, but it is now found worldwide to be associated with humans and is probably the most widely distributed of all the pest cockroaches. It is omnivorous, constantly multiplying, with many overlapping generations often living together and completing a full life cycle in about 100 days.
The German cockroach is a social insect, but unlike some royal colonies of ants and bees, it forms looser, more egalitarian, and democratic alliances. All adults can breed and contribute to group decision-making, rather than pandering to the queen. Unfortunately for us, German cockroaches are also rapidly evolving resistance to a wide range of pesticides, some even an aversion to glucose used in poisonous sugar baits.
Madagascar hissing cockroaches
The Madagascar sizzling cockroach (Gromphadorhina portentosa) is a large wingless cockroach native to Madagascar and inhabits tropical lowland rainforests. It can grow up to 3 inches long and 1 inch wide, and is known for its hissing sound from the breathing holes in its abdomen. Researchers have identified at least four different amplitude patterns and purposes for hissing: male combat hissing, two courtship and mating hisses, and loud alarm hisses that startle predators. Males establish territory and protect them from other males.
The species is popular as a pet and has appeared in some zoos and aquariums. Like many other cockroaches, it is also a harmful substance that plays an important role in the nutrient cycling process of its native forests.