There are many animals that breathe through their skin, although some of them, due to their size, must be combined with other types of breathing or modify the shape of your body to increase the surface area/volume ratio.
In addition, we must know that animals that breathe through their skin have an integument or extremely fine epidermal tissue so that the exchange can take place gaseous. Likewise, they must be aquatic, be closely linked to water or live in extremely humid environments.
Have you ever wondered what animals that breathe through their skin are called? In this article on our site we will talk about animals that breathe through their skin, what other breathing mechanisms exist and other curiosities about the animal world, keep reading!
Types of respiration in animals
In the animal kingdom there are many different mechanisms of respiration. Whether an animal has one type or another will depend on many factors, one of which is whether the environment in which it lives is terrestrial or aquatic, whether it is a small or large animal, whether it flies or not, or whether it undergoes metamorphosis.
One of the main types of respiration is through gills Gills are structures that can be inside or outside the animal and allows them to take in oxygen and release carbon dioxide. The animal group with the greatest diversity of gills is that of aquatic invertebrates, some examples are:
- The tube polychaetes, marine annelids, grow tentacles that they use as gills and to feed when there is no danger.
- Starfish have gill papules that act as gills. In addition, their tube feet would also act as gills.
- The Sea Cucumber has a respiratory tree that empties into the mouth (aquatic lung).
- The limulus or horseshoe crabs have booklike gills covered by gill plates that the animal moves rhythmically.
- The gastropods have gills that develop from the mantle cavity (a special cavity that mollusks have in their bodies).
- lamelibranchs, a type of bivalve, have laminated gills with projections for mixing the medium.
- cephalopods have laminated gills without cilia. The mantle is the one that will contract to move the medium.
Other animals that breathe through gills are fish. If you want to know more about this, do not miss the article How do fish breathe?
Tracheal respiration in animals is another important type of respiration that occurs mainly in insects. Animals that exhibit this type of breathing have structures on their bodies called spiracles through which they take in air and distribute it throughout the body.
Another respiratory mechanism is the one that uses lungs This type is widespread in vertebrates, with the exception of fish. In reptiles, for example, there are unicameral and multichambered lungs. In smaller animals like snakes, they will use single-chambered lungs and when they are larger, like crocodiles, multi-chambered. They have a bronchus that runs through the entire lung, it is a reinforced cartilaginous bronchus. In birds, there is the parabronchial lung, which consists of a set of bronchi arranged in a grid with a series of air sacs. Mammals have lungs that can be divided into lobes.
Finally, there are animals that breathe through their skin, which we'll talk about next.
Animals with skin respiration
The cutaneous respiration, as an exclusive form of respiration, occurs in very small animals. Since they have few metabolic requirements and being small, the diffusion distance is small. When these animals grow, their metabolic requirements and volume increase, so diffusion is not enough, so they are forced to create another type of respiration.
In animals of a somewhat larger size, they either have another mechanism for breathing or acquire an elongated shape. In worms, having an elongated shape increases the surface-volume ratio, being able to continue with this type of respiration. Although they must be in humid environments, and must have a fine and permeable surface.
The amphibians, for example, have various types of respiration throughout their livesWhen hatching from the egg, the small tadpoles breathe through gills and skin, the gills lose full functionality when the animal becomes an adult. The skin, when they are tadpoles, serves both to capture oxygen and to release carbon dioxide. Upon reaching the adult state, although the function of capturing oxygen is reduced, that of releasing carbon dioxide increases.
Examples of animals that breathe through their skin
To learn a little more about the animals that breathe through their skin, we show you a list of animals with permanent skin respiration or in some period of their life.
- Common earthworm (Lumbricus terrestris). All earthworms breathe through their skin throughout their lives.
- Medicinal leech (Hirudo medicinalis). It also has permanent skin respiration.
- Giant fire salamander (Cryptobranchus alleganiensis). Breathe through lungs and skin.
- Northern Brown Salamander (Desmognathus fuscus). He breathes exclusively through the skin.
- Iberian newt (Lissotriton boscai). Breathe through lungs and skin.
- Common Midwife Toad (Alytes obstetricans). Like all toads and frogs, they have gill respiration when they are tadpoles and pulmonary respiration when they are adults. Cutaneous respiration is maintained for life, but in the adult stage the release of carbon dioxide becomes important.
- Spodefoot Toad (Pelobates cultripes)
- Common Frog (Pelophylax perezi)
- Golden dart frog or poison dart frog (Phyllobates terribilis)
- Red and Blue Arrow Frog (Oophaga pumilio)
- Sea urchin (Paracentrotus lividus). Despite having gills, they also perform skin respiration.
- Douglas's marsupial mouse (Sminthopsis douglasi). Mammals, due to their metabolism and size, cannot have cutaneous respiration, but it has been discovered that the newborn young of this species of marsupial depend exclusively on cutaneous respiration during their first days of life.
As a curiosity, the human being has cutaneous respiration, but only in the corneal tissue of the eyes.
