In the oceans we find a vast and wonderful biodiversity on which much remains to be studied. Among this fascinating diversity, we find the animals of the order Octopoda, commonly known as octopuses. These attract attention due to their peculiar appearance, in such a way that they have generated various legends and stories about sea monsters, but on the other hand they also generate scientific interest due to various peculiarities that characterize them.
Among the peculiar aspects of octopuses, we find their circulatory system, which is said to have several hearts. But is that true? Do they have several true hearts or just one? If you have ever wondered how many hearts an octopus has, continue reading this interesting article on our site, in which we will clarify this question.
What is the octopus circulatory system like?
Cephalopods, which is the class to which octopuses belong, are considered the most complex group of invertebrates, since although they have common characteristics with the rest of the molluscs, they have significant differences that place them in a different range. The evolutionary process endowed these animals with particular characteristics that make them a highly competitive group in marine ecosystems
Despite the presence of an inefficient pigment to use oxygen, thanks to various adaptive strategies they are able to inhabit from the sea floor to areas near the surface. They are also excellent swimmers, they have important defense and attack systems, but they are also very good hunters.
All these advantages could not be developed without the presence of a circulatory system provided with excellent capacities. Next, we explain in detail what type of circulatory system octopuses have:
- Closed circulatory system: the circulatory system of octopuses is closed, that is, when the blood circulates it stays within the blood vessels.
- Blood vessels with elasticity: Its blood vessels have elasticity, like that of vertebrates, and are contractile.
- High blood pressure: Heartbeats generate significant blood pressure gradients, so these animals have high blood pressure. This is mainly because they have more than one heart.
- Blue blood: the respiratory pigment responsible for transporting oxygen in the blood is hemocyanin, which is made up of copper and gives bluish coloration to the blood of these animals. This is found dissolved in the blood plasma of octopuses, and not in their cells.
- Gills with high oxygen uptake: octopuses and cephalopods in general have a low oxygen transport capacity, an aspect that have resolved with the development of gills with high oxygen uptake and other mechanisms to promote gas exchange.
- They vary the volume of blood in their gills: they have the ability to vary the volume of blood in their gills, depending on the requirements of oxygen at a particular time.
- Viscous blood: they have viscous blood, since although the water content of the blood is high, so is the solid content.
Now that we know more about the circulatory system of octopuses, let's see how many hearts these animals have and why.
So how many hearts do octopuses have?
Octopuses have 3 hearts, one called systemic or arterial and two branchial. Next, we will explain the differences of each.
Systemic or arterial heart
This heart is made up of a ventricle, to which the main arteriesconnect, and two atria that receive blood from the gills. This heart pumps blood throughout the body and is an optimal organ for distributing the high amounts of blood tissue that these animals require.
Gill Hearts
The two branchial hearts are smaller and act as auxiliary pumps, sending blood to the gills, where blood oxygenation will take place so that later it can be distributed to the rest of the body, thus oxygenating it completely.
In the following image we can see where the 3 octopus hearts are located.
Why do octopuses have three hearts?
Despite having several traits that make them quite advanced animals, octopuses have some unfavorable characteristics for their own species. This has led them to adapt or evolve to optimize their survival in the short life span they usually have (3-5 years, depending on the species). Under these circumstances, the presence of the three hearts in octopuses plays an essential role On the one hand, the ability to increase or decrease their blood volume helps them especially in when hunting their prey or fleeing from a predator.
On the other hand, octopuses tend to prefer the seabed, which is often devoid of oxygen. However, their gills are highly efficient at absorbing what little oxygen there may be, even surpassing that of fish, allowing them to access prey that other marine animals cannot reach.
To all this, we must add that aquatic animals are subject to greater pressure than those that inhabit terrestrial ecosystems.
As we have been able to notice, it is thanks to the presence of the three hearts that octopuses have a complex circulatory system, which allows them to have a fairly optimal organism to inhabit the marine ecosystem andsurvive as a species.
Although octopuses are not the only animals with more than one heart, they attract attention due to their peculiar anatomy, but also because scientific studies increasingly show greater singularities of these animals, among which are Find your outstanding intelligence.
Did you know that octopuses are also said to have 3 hearts and 9 brains? But is that true? In this other article on our site, we explain how many brains does an octopus have?
