Vertebrates vs Invertebrates: Difference and Comparison

Earth is a unique planet. It is the only known planet in this vast universe having life. There are different varieties of living organisms in which it is majorly divided into plants and animals.

Animals are further divided into many groups. Vertebrates and Invertebrates are two different groups in which the animal kingdom is divided.

Key Takeaways

1. Vertebrates are animals with a backbone or spinal column, while invertebrates are animals without a backbone.
2. Vertebrates have a well-defined brain and complex nervous system, while invertebrates have a less complex one.
3. Vertebrates include mammals, birds, reptiles, amphibians, and fish, while invertebrates include insects, spiders, crustaceans, mollusks, and worms.

Vertebrates vs Invertebrates

Vertebrates are animals without backbones and include mammals, amphibians, etc. Vertebrates comprise only 3% of animal species. Reproduction occurs through the sexual method. Invertebrates are animals with backbones. They include insects, etc. Invertebrates account for 95% of animal species. 

Vertebrates are animals having spines. It has a defined body structure with a proper central nervous system. Vertebrates are very common animals, but they only consist of 3% of all known animal species, roughly 70,000.

According to body structure and function, they are further divided into five subparts.

Invertebrates are a major part of the animal kingdom as it includes more than 95% of animal species which is around 1.25 million species of animals and still more to discover.

It does not have a spine and a comparatively simpler body structure. It is a vast group that is further divided into many sub-parts.

Comparison Table

Parameters of Comparison	Vertebrates	Invertebrates
Definition	It is a type of animal that has a spine.	It is the type of animal that does not have spines.
Respiration	They have specialized organs like gills and lungs for breathing.	They have various methods for breathing like some animals respire thorough skin.
Reproduction	They reproduce using the sexual method.	They reproduce using the asexual method.
Classification	They are further divided into five subparts.	They are further divided into thirty subparts.
Example	Snake, deer, lion, parrot are some examples of Vertebrates.	Snails, squid, spiders, crabs, earthworms are examples of Invertebrates.

What is Vertebrates?

Vertebrates are animals having vertebral columns. Vertebrate is a Latin word meaning joint of the spine. It comprises approximately 70,000 animal species that comprise less than 5% of described animal species.

It consists of various animals like Paedophryne amanuensis, a type of frog of size 7.7 mm to 33 m blue whale.

It is a vast group with common features all the animals have a rod passing through the body made up of multiple numbers of bones, and the main nerve passing through it is known as the spine.

It has a complex and defined body structure. In the case of aquatic life, it has gills; in terrestrial life, it has lungs as a part of the respiratory system.

It originated 525 million years ago, and since then, it has been an evolutionary process that has led to many features that we can see now. It has a central nervous system as a complex body structure that runs through the vertebral column.

It is mainly divided into five sub-parts: fish, amphibians, reptiles, birds, and mammals. Most of them reproduce by the sexual method. Some common examples of Vertebrates are goldfish (fish), frogs (amphibians), snakes (reptiles), pigeons (birds), and cows (mammals).

What is Invertebrates?

Invertebrates are animals that lack vertebral columns. They consist of a wide variety of animals in this group, it has around 1.25 million types of species, and scientists claim that there are still 30 million more species to discover. It is more than 95% of all animal species combined.

Invertebrates word is also made from the Latin word vertebra, here, prefix in means without. The major part of the animal kingdom consists of Invertebrates. Its size ranges from 0.002-inch rotifers to 30 – 33 feet colossal squid.

The oldest fossil of invertebrates is 665 million years old, indicating that many invertebrates, through evolution, changed into vertebrates.

The process of respiration is different for various organisms. Some have an open respiratory system. Some use their skin for the process. Some of them use the sexual method of reproduction, but a major part has adopted the asexual mode of reproduction.

The wide variety of invertebrates is very useful for us. More than 80% of flowers are pollinated by invertebrates, on which we are dependent for our food.

They reproduce rapidly, and they get mature in a few weeks; hence they are a good option for cultivation as they are a good source of protein. There is much other importance of invertebrates in our life that go unnoticed.

Main Differences Between Vertebrates and Invertebrates

1. The main difference between Vertebrates and Invertebrates is that Vertebrates have a long column of bones with a spine, while Invertebrates do not have any such column and spine.
2. Vertebrates have gills or lungs to breathe, on the other hand, Invertebrates have many ways, like some use skin to pass gases, and some use spiracles, etc.
3. Most of the Vertebrates are warm-blooded animals which means their body remains constant, in contrast, Invertebrates belongs to the cold-blooded animal group, which means their body temperature changes according to the surrounding.
4. Vertebrates comprise about 3% of the animal population on Earth, whereas Invertebrates include more than 95% of the animal population.
5. The Vertebrates group of animal is further divided into five more sub-parts, on the other hand, Invertebrates is further divided into thirty sub-parts.

References

1. https://www.taylorfrancis.com/chapters/edit/10.1201/9780429290916-2/relative-importance-vertebrate-invertebrate-herbivores-plant-population-dynamics-michael-crawley
2. https://genomebiology.biomedcentral.com/articles/10.1186/gb-2010-11-6-r59