Between The animals that manage to breathe underwater Are mammals, amphibians, insects and fish that live under specific conditions that allow them to comply with the breathing process.
These species have developed throughout their existence mechanisms of adaptation to the environment. Therefore, it is important to explain how these living things work in the environment where they live.
Depending on the type of animal we will analyze how it is the respiration of many of these species that manage to survive under special conditions.
Respiration of fish and amphibians
For the Administration of Children and Families of the United States Department of Health and Human Services, the breathing process of fish and amphibians is defined as follows:
"Fish can live in a particular form of water. For example, a fish that lives in salt water in the ocean would not be able to live in the fresh water of a lake. Like other living things, fish breathe oxygen. Instead of getting oxygen from the air around them, they absorb oxygen from the water around them through the gills.
Gills are the respiratory organs of aquatic animals made up of sheets that protect their body and some internal organs.
They allow oxygen to be taken from the water, which enters through the mouth and the blood vessels in the gills transport the oxygen to the blood. Amphibians perform the process of metamorphosis from which they also breathe through the lungs.
Now, there are differences between the forms of breathing through the lungs and gills. For example, whales and dolphins have lungs like humans, but they rise to the surface to breathe because they breathe through the nostrils located at the top of their heads.
In the case of fish, these have gills and breathing occurs when the fish opens and closes their mouth; When opening the mouth, the water enters while closing it, pushes the water towards the gills.
Aquatic mammals must perform this process of taking oxygen from the surface constantly, in order to live in the environment that surrounds them. The fish take from the water - sweet or salty - the oxygen taken by the gills and these carry them to the rest of their body.
With respect to the function of the internal gills of fish, the process is as follows: when the fish breathe, take a morsel of water at regular intervals. It moves to the sides of the throat, forcing the water through the gill opening so that it passes over the gills outside.
In this way the fish can breathe continuously, using the external and internal gills periodically.
Breathing of aquatic insects
Some insects pass the early stages of their development in the water. There are species that come to live in the air.
Some examples of this type of animals are the dragonflies, nymphs, and other species that are born being aquatic larvae.
Like all animals, these insects also need to convert oxygen to carbon dioxide to survive. The breathing process in this case occurs through holes that are on the sides of their bodies, called spiracles.
Spiracles are openings in a series of tubes from the body of the insect that carries oxygen to the most important organs. In the aquatic insects an adaptation has happened in this system to be able to spend part of its life under the water.
About immersion of aquatic mammals
A fascinating point regarding the breathing of aquatic mammals is the way in which marine vertebrates adapt to the pressure on their bodies when they are submerged, very contrary to the Invertebrates of the water.
While these animals do not breathe underwater, they are able to hold their breath for long periods, which is a subject of study for scientists and researchers.
Of course, the lungs and other organs involved in respiration, as well as other susceptible organs, are affected by immersion at great depths, being"crushed"under such pressures.
However, the ability to adapt to these conditions avoids lung collapse and damage to other organs, thanks to the thoracic cavity and, in particular. The middle ear of these marine species possess a specialized physiology that protects them and gives them the ability to stay long under water.
The thoracic walls of marine mammals are able to withstand complete lung collapse.
On the other hand, the specialized structures of their lungs allow the alveoli (small sacs that form part of the respiratory system and where the gas exchange between breathed air and blood occurs) to collapse first, followed by the terminal airways.
Such structures may also assist in re-inflation of the lung after immersion by means of chemicals called Surfactants .
With respect to the middle ear, these mammals possess cavernous sinuses specialized in this organ, of which they are presumed that they remain submerged in blood while the immersion is happening, being filled in this way the air space
It is surprising how different species are able to function in their own environments, especially with respect to the breathing process - oxygen inhalation and carbon dioxide exhalation - in environments as diverse as air and water.
Lungs and gills are complex structures, adapted to extremely different conditions but ultimately achieve the same goal: to provide the body with the oxygen necessary for its survival.
References
- Animals I. Fur, Fins, Feathers and More. Teacher's Guide. Retrieved from eclkc.ohs.acf.hhs.gov.
- Harvey. S. (2007). Bailey Gartzet Elementary: Breathing Underwater. Retrieved from: gatzertes.seattleschools.org.
- Kneitinger, L. (2013). Cornell University Blog Service: Life underWater. Retrieved from blogs.cornell.edu.
- Native Ecosystems. Retrieved from gw.govt.nz.
- Page 6 University of California Museum of Paleontology. Diving Physiology of Marine Vertebrates. Retrieved from ucmp.berkeley.edu.