All the living organisms of the world are classified into different groups depending on their features and adaptability. The fishes however confuse the researchers about whether to place them under the category of animals or not. This article reveals the reality behind the classification of fish. Keep on reading!
What Features Are Necessary To Be Classified As An Animal?
The following features are significant to classify fishes as animals:
- It must contain multiple cells.
- It is made up of cells with no cell walls.
- It uses food to produce energy.
- It reproduces sexually.
- It can move.
- It responds to external stimuli.
Is A Fish An Animal?
According to the scientific definition, yes, fishes are aquatic cold-blooded animals. Further, they bear gills that help them in breathing, and fins help them to swim with agility along the water current. They do not have limbs or digits but do have scaly skin which protects them from any sort of danger.
Which Class Do Fishes Belong to?
The earlier researchers thought of fishes as being amphibians or mammal but the later classification call them vertebrates because they have many features which resembles vertebrates like they have a brain and when hurt they can feel pain. The dominant feature is having a backbone is enough to group them vertebrates.
How Do Fishes Differ From Mammals And Amphibians?
Fishes differ from mammals and amphibians because fishes have fins as well as gills and are found living only in the water. However, some amphibians do have gills while few mammals and amphibians also bear fins and most of them also live in the water but only fishes have the deadly combination of all these three characteristics – enough to distinguish them from the mammals and amphibians.
How Many Types Of Fishes Are There?
There are more than 30,000 species of fish that inhabit the aquatic as well as the marine habitat but in general, the fishes are classified into three basic categories, these are:
- Cartilaginous fish – these are scientifically named Chondrichthyes which mostly include sharks, skates, and rays.
- Bony fish – also called Osteichthyes which includes salmon, eels, and tuna
- Jawless fish – another name is Agnatha, and it includes lampreys and hagfish.
What Strategies Do Fishes Adapt To Live?
The fishes are widely distributed over the globe, they are found living in oceans, lakes, rivers, wetlands, and other water bodies. They usually live deep in the water, but some are also sighted near the coastal regions. For survival, the fish feeds mostly on underwater plants or animals.
Fishes are characterized as aquatic animals as they fulfill all the requirements required to be classified as animals. The classification of fishes is somewhat a difficult task because they show resemblance with amphibians as well as mammals. But the dominant feature of having a backbone marks their classification under the category of vertebrates.