Hissing cockroaches are insects, so they’re not mammals. While they don’t have wings and might not look like other roaches, they’re still part of the same family that all cockroaches belong to.
I didn’t remember everything from high school biology class, so I went to check up on a hard definition of the difference between the two of them. Modern mammals are warm-blooded and have backbones, as opposed to that hard outer shell that insects have.
You might notice that hissing cockroaches don’t resemble other types of roaches. This is due to the fact that they have some neat features that most other species have.
That doesn’t mean that they’re mammals, however. According to what I’ve found from several zoologists, the reason that males create that characteristic hissing noise doesn’t have anything to do with the presence of a voice box.
Rather, this hissing noise apparently comes from a series of openings on the segmented underside of their bodies. These cockroaches force air through the openings, which allows them to hiss.
Definition of a Mammal
Scientists like to debate everything, so I’ve come across a few competing definitions of what a mammal is. However, pretty much everyone agrees that mammals are animals that nurse their young, have a developed brain and have three middle ear bones that give them sophisticated hearing skills.
That definition includes you and me! It also includes other animals like dogs, cats, whales and porpoises.
Insects, however, don’t meet this definition. You could even say that they’re simpler organisms than mammals, though that’s probably not apparent to anyone who might have had trouble getting some tricky insects out of their home!
Fortunately, it’s pretty easy to tell the two orders of animals apart from one another.
Difference Between an Insect and a Mammal
If you’ve ever taken a good look at any little critters living in your garden or around your home, then there’s a good chance you’ve seen a hard shell on the outside of them. This is called an exoskeleton and is very literally a skeleton on the outside of the animal.
Humans, canines and all other mammals keep their skeletons on the inside. Most of the scientists and zookeepers I’ve followed actually use the presence of a strong backbone as proof that a particular creature is a mammal.
Insects tend to reproduce quickly by laying eggs, which hatch into larvae that have to metamorphose into an adult animal. That’s why colonies of insects seem to get so big so fast.
In general, family groups take on very different forms in the insect and mammal worlds. Mammals tend to live either as solitary individuals or in small family groups.
You’re probably quite familiar with the idea of a herd or a pack. Mammals love to sort themselves into these kinds of groups.
On the other hand, hissing cockroaches live in colonies where multiple mating partners start to reproduce.
How Do Hissing Cockroaches Reproduce?
Some biologists I’ve come across have a tendency to write about this topic in really gross detail, but basically hissing cockroaches rub the back ends of their bodies together until the male is sort of locked onto the female. This enables the mating pair to produce some fertile eggs.
Eventually, the female starts to put her eggs into these foam sacks. Some sources I’ve read prefers the term ooethecas to describe them, but in either case they’re essentially organic foam containers that hold the eggs for the two months or so that it takes for hissing cockroaches to hatch.
This process probably sounds pretty alien to humans, who are used to giving live birth. To make things even more weird, the hatching process takes place internally so you could say that hissing cockroaches sort of give live birth as well in some way.
Around 20-60 young cockroaches fit in each of these sacks. They come into this world as miniature insects called nymphs.
These nymphs will have to consume a certain amount of food and need time to grow before they’re able to turn into a mature cockroach that actually looks like the animal we’d normally call a cockroach.
Once they become mature, former nymphs are able to start the mating process all over again. It’s easy to see how a colony of hissing cockroaches can more than double in size in just a short period of time.
It’s been explained to me that the characteristic hissing noise they give off serves several purposes, but one of the most important is to tell potential mates that a mature adult roach is in the mood.
Lifecycle of a Hissing Cockroach
From what I’ve seen, there’s a little debate on the lifecycle of hissing cockroaches when they’re in their native environment on the island of Madagascar. That being said, those who keep them as exotic pets have spelled out a pretty complex lifecycle for these critters:
- Adult males start to hiss, which can attract a potential female mate
- Male and female mating pair rub together until they’re able to produce a fertile egg
- Eggs are deposited into oothecas structure
- Nymphs internally hatch from an egg
- New nymphs start to consume food provided by mother
- White nymphs gradually turn brown and harden
- Female abandons mature nymphs after around seven months
- Offspring become fully mature and look for their own mates
If you plan on keeping them, then you might notice a few differences especially when it comes to the length of time it takes for nymphs to grow. In their native environment, hissing cockroaches have to go looking for decaying vegetable matter to snack on.
They might end up growing considerably faster in a domestic environment since you’re always around to keep them well-fed. Some states actually now have laws restricting the release of domestic hissing cockroaches because they’re able to breed so quickly!