Sea Life

Are Squid Fish? And if They Aren’t, Why is That?

Are Squid Fish And if They Aren't, Why is That

Squids are aquatic creatures that are ocean predators. They swim in the backward direction in the water by moving their arms in the opposite direction as the other creatures do. There are many features possessed by them that help identify them amongst all the aquatic creatures. For instance, they have large eyes, multiple arms (most likely eight or ten) and two tentacles.

Are Squid Fish?

Squid are cephalopods and not fish. Cephalopods are the members of the molluscan class. Cephalopods are generally considered highly intelligent aquatic creatures. The anatomy or the biological characteristics of cephalopods are almost entirely different. Squids are not limited to only a single type or species; rather there are almost three hundred different species of squids. They eat some kinds of fish and some small animals present in the water. So, squids can never be thought of as a fish. 

Squids have some features in common with the octopus (for example, their eight legs) but that does not mean that squids and octopus are the same. They are also different creatures.

Why are Squid Not Fish?

Squids can be categorized as one the types of invertebrate animals and fish are aquatic vertebrates. So, squids can never be fish. The biological and physical characteristics of invertebrates are completely different from those of  fish or vertebrates. Let’s talk about the facts that differentiate squids from fish:

  • Squid are invertebrates and fish are vertebrates as explained earlier. This can actually be considered as a major difference that is enough to claim that squids are not fish. Fish have backbones but squids do not.
  • Squids usually live up to three to five years approximately but many types of fish can live much longer than this. However, some types of squids like larger squids can live up to fifteen years.
  • Majority of the squids have eight legs like octopus. Some squids have ten legs. While on the other hand, fish do not have legs.
  • Surprisingly, squids are one of those rarest creatures that have multiple hearts. Squids have three hearts unlike fish.
  • Fish dominate in the area of water where the oxygen level is high but squids dominate in the areas where the level of oxygen is low.

The Bottom-Line

Squids are not fish. The main reason behind this is that fish are aquatic vertebrates and they have backbones. While on the other hand, squids are invertebrates and do not have backbone. Moreover, there are many other physical and biological facts that differentiate squids and fish like the difference in their maximum lifespan, the number of their hearts and their living patterns.

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