Worms do not have lungs as we do; however, their respiratory system is nothing shy of incredible. They are able to survive severe circumstances by extracting oxygen wherever they can.
However, as is the case with all living things, there are certain situations in which a worm cannot rely on their respiratory system to save them and where it is, in fact, their downfall.
No, you won’t find lungs in a worm’s body. Earthworms use capillaries that line the outer layer of their skin to breathe, distributing oxygen into the worm’s circulatory system, all while releasing carbon dioxide. This process is called diffusion.
Now you know there are ways for worms to absorb oxygen in order to breathe and survive. In this article, we’ll find out in more depth how this works and why it’s important for an earthworm’s skin to stay moist so that they can keep breathing.
How do worms breathe?
They do indeed have mouths, but even they are very different from our own (they have muscles in their mouths to consume their food instead of teeth).
However, when it comes to breathing, they do not need to use their mouths at all.
In fact, worms breathe through their skin. That is why the right environmental conditions are essential to their survival.
For those of us with compost piles, worm bins, or vermicomposting systems, we all know that keeping the containers moist is essential.
Well, this is entirely for the worm’s benefit.
In a dry environment, the worms will not be able to move comfortably through the soil, and they will suffocate from the lack of moisture, potentially dying if they cannot escape to a more suitable environment.
You will have undoubtedly noticed in your lifetime that earthworms are pretty slimy.
That’s because that outer layer of mucus is part of their respiratory system, and they need it to breathe.
Your worms need to remain wet or stay wet within the soil they travel through.
But how does the oxygen penetrate the skin?
How earthworms use diffusion to breathe
In truth, the way that earthworms breathe is fascinating and key to understanding these little creatures a little better.
Earthworms use capillaries that line the outer layer of their skin to breathe.
The capillaries manage to distribute oxygen into the worm’s circulatory system, all while releasing carbon dioxide out of the worm.
That is why the outer layer of mucus on the earthworm is so essential. The earthworms rely on the mucus to provide a passage through which the oxygen can enter and the carbon dioxide can leave.
This is also why we are always told to keep a worm’s environment wet.
If a worm gets too dry, the mucus on them will dry up to, therefore blocking the passageway for the oxygen and the carbon dioxide.
That is why the earthworm dies in the sun because it has suffocated due to the dryness.
Can worms breathe underwater?
Yes – worms can not only survive underwater, many will happily live underwater and in heavy rain, too. However, it’s a temporary measure.
You may have heard that worms exit the ground when it rains due to their risk of drowning.
As it happens, this may not be entirely true.
In fact, studies have shown that worms can live up to approximately two weeks living underwater. Their respiratory system allows them to use oxygen from the water to survive.
However, it is also important to note that the worm will die after those two weeks, or even longer, depending on the worm.
Worms cannot swim, as their bodies are only equipped with small bristles to burrow through the soil.
Eventually, they will not be able to get the amount of oxygen that they need from the water, and they will drown.
So, why do earthworms come out of the soil when it rains? Surely they would be better off avoiding the large puddles and rain sweep?
Well, recent studies have shown that while earthworms do leave the soil during rain storms, this may have less to do with the rain and more to do with what else is lying beneath the soil.
During rain, worms feel vibrations in the soil that mean something to the worm. The vibrations could be from a predator in the soil, moles specifically.
Therefore, in order to avoid predators, the earthworm will rise to the surface of the soil in an attempt to hide from their chasers.
Can you suffocate a worm?
As was mentioned, yes, you can suffocate a worm in multiple ways.
When we get dehydrated, we can still breathe. However, as worms need moisture to keep their bodies wet in order to breathe, being dry is a sure way to suffocate.
In fact, a worm in direct sunlight with no means of getting wet will dry up, suffocate, and die within one hour.
However, when it comes to water, worms are far more efficient than we are.
Although we dry pretty slowly, it will happen within a minute’s time. On the other hand, worms can take up to two weeks, and some even longer, to drown.
However, it is essential to note that they are not able to survive full time underwater, and eventually, they will suffocate and die.