If you’ve seen dead roaches, you know most of them die in a uniform-like fashion - lying on their backs with legs facing upward.
But have you ever wondered why they do this? Wondered why roaches die on their back? How do these bugs end up in a very unlikely position when they get killed? Well, the reasons behind it are actually quite simple.
Roaches have a peculiar body shape. They are very flat but bulky. Their entire body is only supported by 6 hairy and spiny legs that don’t extend sideways, so they aren’t much use when they topple over.
However, roaches have been known to flip to the right position if there’s something else in their surroundings. These can be debris on the ground or a wall that they can cling to. But without help from these outside forces, a cockroach on its back doesn’t have any chance of ever getting up. It just dies from hunger and dehydration.
Neurotoxins in Pesticides
Roaches don’t really have a particular dying ritual. They can lie on their backs or face downward, there’s no preference to how they’re positioned when they’re killed.
However, when you do see these insects on their backs. It’s generally because of how they’re exterminated. According to Traps for Roach, modern pesticides and chemicals used for controlling pests have organophosphate nerve poisons that can affect a cockroach’s nervous system. These substances inhibit an enzyme called cholinesterase that’s responsible for breaking down the neurotransmitter, acetyl choline (ACh).
So whether it’s through a bait, a spray or the fumigation method, more ACh in a roach’s body make it move frantically and have wild spasms. It then flips over, eventually loses muscle strength and die flat on its back.
Suspected Inherent Reaction
When roaches are exposed to poisons, they don’t always flip over and die. However, some sources disagree with this. Accordingly, the involuntary response of toppling over due to muscle spasms and contraction is something inherent and sort of “automatic” for these roaches or even other bugs. But this has not been proven since there haven’t been major studies about it.
Not all roach species die this way
The good news for roaches is that not all of them die a horrible death of their backs flat on the floor.
Accordingly, most “die-on-their-backs” scenarios happen to indoor roaches. That’s because our floors are smoother with virtually no debri compared to soil. Outdoor roaches, specially the species that live in forests don’t usually have to face this kind of death since they have a less chance of encountering pesticides and that small things like rocks, leaves and other debri can help them get back to the right position.
Overall, there’s really no special reason why roaches die on their back. They just end up that way because of biological traits and certain situations. But if you see these bugs in this position, at least you know that the treatment you’re using to get rid of these bugs is actually working.