We often confuse lizards and reptiles as the same and prefer to call them a class. It is shown that the two of them have some basic differences such as the term reptiles is used to define a class of animals whereas lizards account for only a few per cent.
Lizards vs Reptiles
The main difference between lizards and reptiles is that the lizards belong to the class Squamata and has further categories under it whereas reptiles belong to the class of Reptilia which has classifications like Anapsida and Eureptilia and they further include classes like Squamata, Crocodilia, etc.
Lizards have more than 6000 species which are found in most of the continents which excludes Antarctica. They vary in size and can range from chameleon to a 3-feet long lizard. They are Squamate reptiles and exclude snakes, Amphisbaenia and fall under the group paraphyletic and have many antipredator adaptations like venom, camouflage, etc.
Reptile is the word that generally refers to all the animals under the class Reptilia and it comprises all amniotes excluding the mammals and their relatives. The reptiles have existed for more than 312 million years and are often said to have originated in the Carboniferous period and includes animals like crocodiles, turtles, amphisbaenians, etc.
Comparison Table Between Lizards and Reptiles
| Parameters of Comparison | Lizards | Reptiles |
| Class of animals | Squamata is the classification of lizards which falls under the class Eureptilia. | Reptilia is the class of all the animals following under it |
| Size of the species | They may have sizes ranging from two cm to three metres. | They may have sizes varying from one cm and can be as large as seven metres. |
| Number of species | It has around four thousand species under it. | Although lizards are the biggest class under it, reptiles have more than eight thousand species |
| Time of origin | They are said to have originated in the late Permian period and are said to be 260 million years old. | They are said to date back for more than 310 million years and have originated in the Carboniferous period. |
| Abilities | The most common ability in a lizard is autotomy or the ability to grow body parts which are cut off. | They are most famous for antipredator adaptations which include features like camouflaging, venom attack, growing size, etc. |
| Examples | Chameleons, monitors, skinks, iguanas, Gila monsters, geckos, etc. | Turtles, crocodiles, gharials, lizards, snakes, tuatara, amphisbaenians, etc. |
What is Lizard?
Lizards fall under Squamate reptiles along with the snakes and can be found everywhere except Antarctica due to the weather conditions. They are different from snakes because of the presence of limbs and outside ears. They are generally quadrupedal means they run on their legs but they have a class that is legless.
They are said to have territories and can fight for that. Mostly the males are said to change their colours for attracting the mates and also threatening the enemies to secure their space as well as the mates.
Lizards like Komodo are said to even eat species as big as water buffaloes but other feed on small insects. They are also said to have to sit and wait for the prey which means that they carefully observe their prey for a while and then attack suddenly.
They are said to have various techniques for being safe in which camouflaging and venom attacks are highlighted especially for the lizards. They can be as small as 2cm and can be as large as 3m and are considered a good omen when seen on some of the festivals especially in India. Some of the species of lizards are Chameleon, Draco. Komodo, Skinks and Iguanas.
What is Reptile?
Reptiles are generally cold-blooded animals and have a large number of classifications under them. They fall in between the Amphibian and Birds group and consist of more than 8000 species that are spread all over the world.
According to the Linnaean classification they were treated differently from the birds but the class crocodilians have shown a variety of common features with the birds rather than reptiles and therefore according to the new and modern cladistic classification both of them are placed in the same class and named it as Clade.
They have a variety of approaches for being safe from predators and all of the sub-classes have different techniques. The snakes rise and open their head to scare off the invader and if this doesn’t work they go for a venomous attack which is used mostly by cobras, anacondas, etc. For the crocodiles, they tend to enlarge their body.
The common species under this class are lizards, crocodiles, gharials, turtles, etc.They lay eggs and the mammals and ancestors are not included under them.
Main Differences Between Lizards and Reptiles
- The lizards are of the class Squamata which is a small class under the classification of reptilia whereas reptiles are used to refer to all the animals that are under the class reptilia.
- Lizards have different sizes and they can be anywhere between two cm to three metres. In comparison to this reptiles have a larger range of sizes which varies from one cm to 7 metres.
- Lizards are said to be found and originated in the Permian period which was about 260 million years ago, whereas reptiles first originated in the Carboniferous period which was about 310 million years ago.
- Lizards are said to have the ability of autotomy which means they can rebuild their organs after it is cut off whereas reptiles have few common features which help them against a predator including venom attacks, camouflaging, etc.
- Lizards make 59% of the class reptilia and have more than 4000 species whereas the class itself has more than 8000 species.
Conclusion
Lizards are a part of the class reptilia and have many common features to the class but they also show some of the peculiar properties which are only shown by them which also excludes some other animals in the Squamata class like snakes who do not have limbs. Reptiles refer to a general class that continues to bifurcate further and contains many similar types of species.
Both of them have cold blood and use a set mechanism to fight their predator like venomous attacks, enlarging bodies, etc. and they are also territorial. It means that they have their area and fight other males for it. For the same, they change colours and attract mates and intimidate enemies.
References
- https://www.nature.com/articles/s41586-021-03834-3
- https://academic.oup.com/zoolinnean/article-abstract/84/2/97/2648638