Life began in water, so it is not surprising that a large part of the animals that exist today breathe in this environment. Many of these beings breathe through their skin, diffusing oxygen to the blood through this pathway. However, when in species of a certain size, respiration through the skin is not enough. Then, the gills appeared. In this article on our site we will talk about how gills work and learn about some animals that breathe through gills
Gill respiration in animals
Respiration through gills is carried out by those animals that live in water, such as fish, some amphibians, molluscs, arthropods, worms, etc. The gills are respiratory organs that are usually found on both sides of the head and, during development, originate from one of the embryonic layers.
The gills are usually found in natural crevices of the body and are presented as a series of intertwined filaments with a high blood supply, through which passes the oxygen-rich water, which enters through the mouth, and gaseous exchange occurs.
Discover more about how they work in our article about how fish breathe, where we will explain where they are and how their respiratory system, essential to fully understand the process! Likewise, it should be noted that there are also lungfish which, in addition to gills, also have lungs.
Here is a list of animals that breathe through gills:
1. Giant manta (Mobula birostris)
The giant manta is a type of chondrichthyan fish, that is, a fish with a cartilaginous skeleton instead of bony. Due to its anatomy, the giant manta presents its gills in the ventral area of its body, where we can see five pairs of gill slits.
It is the largest species of blanket that exists. It has a circumtropical distribution, so it inhabits all warm water areas It commonly lives on shallow reefs or on the surface near the coast. It is also occasionally seen on sandy bottom areas and seagrass beds.
two. Whale shark (Rhincodon typus)
The whale shark, like the rest of the shark species, needs to be in constant movement so that the water passes through its gills It has five gill slits on each side of its head, very close to its pectoral fins.
This shark also has a circumtropical distribution, but it goes deeper into temperate waters, in addition to the Mediterranean Sea. They usually dive to depths of almost 2,000 meters, it is thought that to carry out the feeding process. They are very large animals, individuals have been found that exceeded 20 meters in length.
3. Pocket lamprey (Geotria australis)
The lamprey is an agnathous (jawless) fish that breathes through gills. But these fish have a special characteristic, which is that they are parasitic animals, so when they are feeding they cannot take in water through their mouths. Then what is known as concurrent respiration occurs, the water enters and leaves through the same gill slits.
This species is native to the southern hemisphere, except for the African coasts. In addition, they are anadromous animals, they go up freshwater rivers to lay their eggs and when they hatch, the small juveniles travel to the oceans where they will live until their age adult. It is considered one of the oldest animals in the world.
4. Giant Clam (Tridacna gigas)
The giant clam is a bivalve mollusk that lives on the reefs of the Pacific and Indian oceans. They breathe through gills. They take in the water through a absorbent siphon and expel it through another siphon, this time exhaling. In clams, in addition to respiration, the gills have other functions, such as digestive, excretory and osmotic
5. Nudibranchs
Nudibranchs are an order of gastropod molluscs known as " sea slugs". They have very varied and striking colors. The gills are characterized by being outside the body and at the end of it, as if they were a tuft of antennae.
6. Crested Newt (Triturus karelinii) larvae
The crested newt is a species of urodele amphibian that inhabits the region of Turkey and Bulgaria. Although in their adult stage they breathe through the lungs and skin, like the vast majority of amphibians, in their juvenile stage they breathe through gills
7. Marine polychaetes
The polychaetes are a class of the phylum annelids. They are segmented worms with a multitude of setae, which are hairs that come out on both sides of their body. These animals usually breathe through the integument, that is, their skin. But the larger ones, as they need an extra supply of oxygen, have gills to breathe, in addition to their own skin.
8. Great blue octopus (Octopus cyanea)
Octopuses are cephalopod molluscs whose main characteristic is their ability to camouflage These animals breathe through gills on their back of the head. They have a siphon through which they take in oxygen-rich water and expel the water together with carbon dioxide.
Also discover on our site 20 curiosities about octopuses, based on scientific studies!
9. Yeti Crab (Kiwa hirsuta)
The yeti crab gets its name from its white color and its body covered with setae, where bacteria whose function is still unknown are housed. It is a type of large hermit crab, about 18 centimeters. They breathe through gills protected by their shell. The water reaches the gills through holes behind the eyes.
10. Bullfrog Tadpoles (Lithobates catesbeianus)
The bullfrog is an anuran amphibian native to North America. It is considered an invasive species in other parts of the American continent and Europe, which is why keeping a bullfrog as a pet is prohibited in certain countries. As in the rest of frogs and toads, tadpoles breathe through gills that will disappear after metamorphosis.
Other animals that breathe through gills
Have you been wanting more? There are many animals that breathe through gills, so here is a list with 15 examples more:
- Barracuda (Sphyraena barracuda)
- Sunfish (Mola mola)
- Mediterranean Moray Eel (Muraena helena)
- Clownfish (Amphiprion ocellaris)
- Golden (Sparus aurata)
- Spiderfish (Trachinus draco)
- Leopard catfish (Pimelodus pictus)
- Great Hammerhead Shark (Sphyrna mokarran)
- Sole sole (Solea solea)
- Turbo (Scophthalmus maxima)
- Tadpoles of the Big-headed Tree Frog (Leptopelis hyloides)
- Tadpoles of the fire salamander (Salamandra salamandra)
- Common cuttlefish (Sepia officinalis)
- Coquina (Donax trunculus)
- Zebra mussel (Dreissena polymorpha)
