Lizards are tetrapod (four-legged) animals that belong to the Reptilia class in the phylum Chordata. Phylum Chordata is one of the many phyla of the animal kingdom (Kingdom Animalia).
More than 6,000 species of lizards exist in the world. They vary in size, weight, appearance, color, behavior and many other aspects.
Are lizards reptiles or amphibians?
Lizards are reptiles. Although reptiles share some similarities with amphibians, the two groups of animals are also very different.
Examples of reptiles include lizards, skinks, geckos, snakes, crocodiles, alligators, chameleons, and turtles. While examples of amphibians include frogs, newts, and salamanders. From these two groups of examples, I’m sure you can clearly see that reptiles/lizards are quite different from amphibians.
In the next section, I will share with the similarities between lizards and amphibians. It is the similarities between lizards and amphibians that cause some people to confuse lizards with amphibians.
So what are the similarities between lizards and amphibians?
Many people confuse lizards with amphibians because lizards share several similarities with amphibians. Below are the similarities between lizards (reptiles) and amphibians.
- Lizards and amphibians are cold blooded
- Lizards and amphibians belong to the phylum Chordata (have a backbone)
- Lizards and amphibians change the color of their skin
- Lizards and amphibians have good eyesight
- Lizards and amphibians have varying defensive responses
As you can see above, lizards share many similarities with amphibians. This is why it is easy for some people to mistakenly assume that they belong to the amphibian group. Lizards are not amphibians. They share many similarities with amphibians, but they are also very different from amphibians, as you will see below.
So what are the differences between lizards and amphibians?
As stated earlier in this article, lizards are reptiles. They are classified as reptiles because they look and behave like reptiles and are very different from amphibians. Below are the main differences between lizards and amphibians.
- Lizards, like most reptiles, breathe exclusively through the lungs. In contrast, most amphibians, including frogs, salamanders, and newts, can breathe through their lungs and through their skin.
- Lizards, like all reptiles, have several cervical vertebrae. This allows them to move/turn their heads significantly. In contrast, amphibians have only one cervical vertebra, so they cannot move their heads much.
- Lizards have dry, scaly skin like most reptiles. Their skin protects them against water loss. This is the reason why they can go to many different habitats. In contrast, amphibians mostly have smooth, moist skin that does little to protect them against water loss. This is the reason why they must live near a constant body of water.
- Lizards, like most reptiles, lay their eggs primarily on land. In contrast, all amphibians lay their eggs in wetlands.
- Lizards, like all reptiles, do not undergo metamorphosis. In contrast, all amphibians undergo metamorphosis.
- Lizards, like most reptiles, have an organ known as Jacobson’s organ located in the roof of their mouth which allows them to easily locate prey, predators and mating partners. In contrast, amphibians do not have this organ. They use other mechanisms.
As you can see from the above points, lizards are much more reptile-like and very different from amphibians despite some similarities with them (amphibians). Because lizards share more similarities with reptiles and are significantly different from amphibians in some ways, they are classified as reptiles. If it looks like a duck, swims like a duck, and quacks like a duck, then it’s a duck. In this case, the above points prove that lizards look like reptiles, live like reptiles, and do everything like reptiles. They cannot therefore be anything other than reptiles.
So now you know why lizards are reptiles and why they are too different from amphibians to be classified or grouped together as amphibians.
Frequently Asked Questions About Lizards
How many species of lizards exist?
There are over 6,000 species of lizards known to man. The many species vary in size, shape, appearance, body systems, abilities, and more. Examples of lizard species include skinks, monitor lizards, Gila monsters, geckos, chameleons, and iguanas. Chameleons and iguanas are different enough in appearance from other lizards that people assume they are not lizards but they are.
Where are the lizards found?
400; »>Lizards live on all continents of the planet, except for Antarctica. Antarctica is just too cold for them as cold-blooded animals. Different species of lizards prefer different habitats as they have adapted to living in specific habitats.
Are lizards social or solitary animals?
Most lizards are solitary animals. They prefer to do things alone. However, many lizards are social and like to live in numbers.
Which is the smallest lizard and which is the largest lizard?
The smallest lizard known to man is the dwarf gecko. He is only 1.6cm when fully grown, so he is a very small gecko/lizard. He lives in the US Virgin Islands. While the largest lizard known to man is the Komodo dragon.
The Komodo dragon can grow up to 10 feet long and weigh up to 300 pounds. In short, it’s a massive animal by most measures. He’s so big he can grab and kill a water buffalo. The lizard is only found on the Indonesian islands of Gili Dasam, Gili Montang, Komodo and Rinca.
Do lizards see color?
Most lizards cannot see color. In other words, they don’t like you and me. Therefore, colors don’t mean much to lizards. They generally use their eyesight and other senses to go about their business. For example, many lizards are known to smell with their tongues like snakes, which helps them find and follow clues to hide from predators and prey or to find mates.
Some lizards, however, see color. They see colors and use colors to talk to each other, especially during mating season when the need to communicate is very high. The most common lizard that can see color is the iguana.
Are lizards poisonous?
No they are not. Nearly 100% of all lizards known to man are non-venomous. Only two lizards are known to be poisonous to humans and they are the Mexican bearded lizard and the Gila monster.
What foods do lizards like?
Different species of lizards like different foods. Some are insectivorous/carnivorous, some are herbivorous and some are omnivorous. Insectivorous/carnivorous lizards are those that eat prey like insects and small animals. Herbivorous lizards are those that eat strictly plant matter and omnivorous lizards are those that eat everything.
Captive lizards are known to prefer to eat grasshoppers, ants, flies, crickets, flowers, fruits, and leaves.
The most well-known herbivorous lizards are iguanas.
Why do lizards bask in the sun?
Lizards like to bask in the sun because they are cold-blooded animals. So they bask in the sun to warm up after spending hours in the cold earth or elsewhere. What I’m trying to say is that basking lizards do so to regulate their temperature and avoid freezing.
Because lizards don’t generate their own heat like warm-blooded animals, they need the sun. For this reason, if you want to keep a lizard pet, you need to buy a lizard platform and a heat lamp. This is because your lizard tank/enclosure is obviously going to be inside your house and since the heat from the sun won’t reach your lizard, you will need to recreate it by having a heat lamp above your tank.
If you get a heat lamp, your lizard will probably die sooner rather than later.
Can lizards walk on water?
No, lizards cannot walk on water. However, one species of lizard – the Jesus Christ lizard – can walk and run over water. The lizard, also known as the basilisk lizard, is commonly found in rainforests and streams in South and Central America.
Most lizards have a secret “third eye”?
Most lizards have a series of nerves on their foreheads that allow them to know direction like a kind of natural GPS.
Lizards are definitely reptiles. They look like reptiles, walk like reptiles, and have reptilian features. So they can’t be anything but reptiles. They have some similarities to amphibians, but they are also very different from amphibians. They are therefore reptiles and that is what they have been since classifications of animals began to be included in biology texts.