Buzz
The cockroach is an incredibly annoying and persistent insect that we humans still can't quite tolerate—and probably never will. Despite this, roaches have managed to coexist with us for centuries, seemingly thriving in this ongoing relationship.
There are numerous fascinating and gross facts about roaches that many of us remain unaware of. For instance, these superbugs can go on for weeks even after losing vital body parts, they have a strange affection for our ears, and they can bite us when we stop feeding them.
10. They Can Survive Without Their Heads For Weeks
Cockroaches are incredibly resilient survivors, making them nearly impossible to eradicate. Even decapitating a roach doesn't guarantee its death, as it can live for weeks without a head. The roach eventually perishes because it can no longer eat or drink without a mouth.
Cockroaches can survive decapitation because they don't rely on their heads the way humans do. While we die soon after losing our heads due to blood loss and decreased blood pressure, cockroaches have minimal blood and low blood pressure. Their necks simply clot, and they continue moving around like nothing happened.
Even if humans could somehow avoid the massive blood loss and drop in blood pressure, we would still not survive because our bodies need nerve connections to the brain and our noses and mouths for breathing.
Roaches' bodies function independently of their small brains, and they breathe through tiny openings in their bodies. These unique traits allow them to live for weeks without a head. They only die from hunger and thirst, as they can't eat or drink through their skin.
Interestingly, a cockroach's head can remain alive for several hours after decapitation, as seen by its antennae moving. In fact, the head can stay alive even longer if refrigerated and provided with nutrients.
9. They Despise Human Touch
According to a popular cockroach fact circulating on the Internet, these creatures absolutely detest human contact—so much so that they often scurry away to clean themselves off after being touched. But it's not just a matter of discomfort. Cockroaches avoid touch because it can pose a real threat to their survival.
To clarify, cockroaches dislike humans just as much as humans dislike these repulsive insects. Cockroaches instinctively run from larger beings—humans included—because they know that any contact with a bigger creature often spells their doom.
In fact, touching almost any organism could transfer residues that are harmful to the roach. For humans, it's the oils we unknowingly leave behind when we touch things. These oils can interfere with the roach's bodily functions.
The antennae are most affected. While they may seem insignificant to us, they are vital for a cockroach’s survival. Acting as the creature’s nose, they help the roach detect food and potential mates. The oils left behind reduce their ability to smell, which is detrimental to the cockroach.
8. They Are Drawn To Our Ears
You've probably heard stories of cockroaches getting trapped in people's ears, or even crawling deep inside to reach the skull. In extreme cases, the rogue roach might lay eggs in the ear or even perish there.
It turns out, however, that these incidents aren't as common as they should be. Cockroaches should find their way into our ears far more frequently than they actually do.
As mentioned earlier, cockroaches generally avoid humans. But they love dark spaces, which coincidentally is when humans are asleep. And it seems they have no qualms about making regular visits to the sides of a sleeping person.
The wax in our ears releases volatile fatty acids—chemicals also found in foods like bread and cheese. These fatty acids are highly attractive to roaches. If they detect the scent in our ears, they quickly realize that the human ear is snug, warm, and stuffy—just the kind of environment they adore.
And what kind of creature would pass up a free home with free food?
Unfortunately, this creates a dilemma for both the cockroach and the sleeping human. Any movement inside the tight confines of the ear could cause the person to subconsciously scratch, pushing the roach deeper into the ear or even killing it if enough pressure is applied. Either outcome is bad for both the ear and its owner.
A live cockroach could end up deep within the ear or even inside the skull. The spines on the roach’s legs might damage the inner ear, leading to infection or even hearing loss if the eardrum is compromised.
A dead cockroach presents its own set of problems, with a squashed one being an even bigger concern. The insides of cockroaches contain harmful bacteria that could cause serious health issues.
7. They Are Capable of Biting Humans
Cockroaches are omnivores, consuming both plants and animals. They will eat just about anything—even a living human. Yes, you read that right! Roaches can bite humans. (A quick personal note: I've been bitten once, and the sting-like bite was so intense it woke me from my sleep.)
To clarify, cockroaches don't actively seek out humans to bite. They generally prefer other sources of food. If a human attacks, they won’t bite back, instead opting to flee.
However, when roaches are in large numbers and food becomes scarce, they may resort to biting humans or even pets. Despite this, they still prefer to avoid biting people when possible. Most bites occur when a roach finds small food crumbs on a sleeping human's body.
These food particles are typically found around the fingers, hands, and legs—where most bites occur. The bites can be painful and have been likened to being zapped by a giant mosquito the size of a roach. It's recommended to treat the bite afterward, as the roach could introduce bacteria into the body.
6. They Used To Enjoy Sugar But Now They Can't Stand It
Cockroaches have a sweet tooth. If you leave candy, cakes, fruits, and sugary juice exposed around your home, they'll happily approve. Leave raw sugar out, and they'll be your best friend forever.
Pest control companies uncovered this fact in the 1980s. They noticed that sprinkling sugar in certain areas would quickly attract roaches. Using this information, they began luring roaches with glucose mixed with insecticide. When the roaches returned to their hiding spots, the poisonous meal took care of them.
The dead roaches were often eaten by others, which makes sense since these pests will consume almost anything. The scavenging roaches then met the same fate, as the bodies of the dead ones still contained the poison. This continued for a while until the cockroaches figured out that sugar was the culprit.
Eventually, cockroaches started avoiding sugar. Their senses adapted to recognize sweet sugar as bitter. Pest control companies learned this too and swapped glucose for fructose, another type of sugar. But the roaches caught on quickly and began avoiding fructose as well.
Scientists have traced this fascinating change back millions of years, when cockroaches first developed the ability to recognize sweet but toxic parts of certain plants as bitter. This ability was genetically suppressed as they began living around humans, only to resurface when humans started poisoning their food.
5. Termites Are Actually Cockroaches
Termites and cockroaches both belong to the order Blattodea, meaning termites are essentially a type of cockroach. Surprisingly, termites were not classified as cockroaches until 2018. Before that, they were categorized under the order Isoptera.
Research into the shared traits of termites and cockroaches began in 1934, when scientists noted that their guts contained similar microbes. A paper published in 2007 definitively confirmed that they were related, leading to a revision in their taxonomic classification, grouping them within the same family.
In fact, the paper proposed that the orders Blattodea (for cockroaches) and Isoptera (for termites) should be regarded as subfamilies under a new family named Termitidae.
At the time, several members of the Entomological Society of America (ESA) rejected this idea, as they were unwilling to classify termites as cockroaches. Moreover, there was already a Termitidae family in the taxonomic classification, which could lead to confusion with the newly proposed Termitidae family.
However, in 2018, the ESA reconsidered and agreed to classify termites as cockroaches after a vote. They chose to reassign the termite order Isoptera to a suborder and place it within the cockroach Blattodea order, rather than creating a new family as suggested in the 2007 paper.
That doesn't mean you should refer to termites as “cockroaches,” though. It’s better to call termites “termites” and cockroaches, “cockroaches.” It's like knowing that a tomato is technically a fruit, but not putting it in a fruit salad. In this case, “Knowledge is recognizing that a termite is a cockroach. Wisdom is choosing not to call it a cockroach.”
4. They Can Switch Gears While Running
Anyone who's ever tried to catch or kill a cockroach knows just how quick they can be, especially given their size. It turns out, this isn't a surprise—some cockroaches are capable of adjusting their speeds.
Scientists have compared this ability to how horses go from trotting to galloping or how cars shift gears to accelerate. Cockroaches don’t exactly switch gears like a car, as there's no such thing as a 'roachmobile,' but they change their running speeds by altering the positioning of their legs.
This phenomenon was first observed in a 2017 study on the Nauphoeta cinerea cockroach. Much like other roaches, it runs away when it senses a large threat. In its usual escape response, the roach uses its middle leg on one side of its body, while the front and hind legs on the opposite side touch the ground at the same time. This movement is known as the alternating tripodal gait.
However, the alternating tripodal gait isn’t the fastest and consumes a lot of energy, leaving the cockroach unstable. To address this, the roach switches to a more efficient method known as the metachronal gait. In this pattern, all the legs on one side lift off the ground in sequence—from front to middle to hind legs—and then touch down in that same order.
3. If They Were To Disappear, The Ecosystem Would Collapse
While cockroaches may be despised by many, they play an essential role in maintaining a balanced ecosystem. If they were to vanish, our ecosystem would face severe consequences.
For starters, the loss of cockroaches would drastically impact the populations of various bird species, as well as rats and mice, all of which rely on roaches as a food source. Although these animals wouldn't disappear entirely—since they also eat other organisms and sometimes plants—their numbers would certainly dwindle.
This reduction in bird, rat, and mouse populations would subsequently affect the animals that prey on them, such as cats, wolves, coyotes, eagles, reptiles, and many more. The ripple effect continues, with some wasp species—whose life cycles depend on cockroaches—ultimately facing extinction due to their food source being wiped out.
The forests would also take a hit if cockroaches were to go extinct. These insects play a crucial role in breaking down decaying organic matter, which is often rich in nitrogen. As cockroaches consume this material, they absorb the nitrogen and later excrete it, enriching the soil and helping plants to grow.
Without roaches, the soil would lose a vital source of nitrogen, making it less capable of sustaining plant life. This would affect creatures that feed on plants and, in turn, their predators. The impact would ripple all the way up the food chain. So, it seems, we may just have to put up with roaches after all.
2. They Can Make Group Decisions
Cockroaches are more intelligent than we often give them credit for. They have the ability to make decisions as a group, much like many other insects and animals.
A few years ago, Dr. Jose Halloy of the Free University of Brussels, Belgium, conducted an experiment to understand how cockroaches think. He placed several roaches in a dish with three different homes and observed how they would choose to divide themselves up.
Dr. Halloy noted that the roaches first gathered together, touching one another with their antennae. Over time, they separated into the homes, evenly distributing themselves. For example, 50 roaches split into two groups of 25 each when provided with three homes, each capable of housing 40 roaches.
One group settled in the first home, while the other took up residence in the second. The third home was left empty. When presented with three homes that could hold more than 50 roaches each, all 50 roaches chose to reside in a single home.
1. Their Brains Could Be Used To Make Lifesaving Drugs
Here’s a disturbing fact that might revolutionize medicine: Scientists are working on developing drugs that could potentially cure deadly antibiotic-resistant bacteria like E. coli and MRSA (methicillin-resistant Staphylococcus aureus) by using chemicals extracted from cockroach brains.
Researchers stumbled upon this discovery while investigating how locusts managed to survive in filthy environments in the Middle East. Cockroaches entered the picture when the researchers aimed to understand how these creatures managed to live in sewage and drainage systems without succumbing to the harmful bacteria that thrive there.
It turned out that the nerves of locusts and the brains of both cockroaches and locusts contained chemicals capable of killing these dangerous bacteria. Though the exact chemicals responsible remain unidentified, researchers are actively working to uncover them, with hopes of using the findings to create antibacterial drugs in the future.
