101 Facts – Lizards by IP Factly
For video footage…
- Komodo Dragon
- Gila Monster
- Blue-tongued Skink
- Frilled-neck Lizard
- Perentie Lizard
- Texas Horned Lizard (Horny Toad)
General Lizard Facts
Anatomy & Senses
Lizards and Humans
Lizards can be found everywhere – on trees, under rocks, in deserts, in jungles, even in the walls and ceilings of our own homes (depending on where you live!). Some of them are small enough to fit in your hand while others are as large as small crocodiles. They have many different features, too, making them some of the most diverse and fascinating creatures in the world.
Lizard by Mohamed Malik
Lizards are reptiles. Like other reptiles, they have dry skin covered in hard scales instead of soft fur or feathers. They are also cold-blooded, which means their body temperature changes depending on their environment.
In particular, lizards belong to the order Squamata, or the order of scaled reptiles. This order also includes snakes, making them the closest relatives of lizards.
Lizards in our backyard by Oleg Shpyrko
There are more lizards in the world than any other reptile. In fact, about 60% of reptiles are lizards.
There are approximately 6,000 species of lizard, about the same number of all mammal species and two times the number of snake species.
Because there are so many species of lizard, it comes as no surprise that lizards can be found almost anywhere in the world, inhabiting every continent except Antarctica, where it is too cold for them to live.
Most lizards live on the ground but there are also lizards that live under the ground, on trees and in human dwellings. Some even live in the water.
Lizard in Water by Chris Williamson
A male lizard is sometimes called a bull and a female lizard is sometimes called a cow or a lizardess. A group of lizards is called a lounge.
Lizards vary greatly in size, from over just an inch long to as long as 10 feet (3 meters) – that’s about the size of a small mom standing on another small mom’s head!
Some Big Lizard! by Yu Ting Lim
The average lifespan of a lizard is about 15 to 20 years. However, some lizards can live over 30 years.
Although there are many species of lizard, many of these are listed as Endangered or even Critically Endangered. The most common threats to a lizard population include habitat loss and predation from animal species introduced by humans.
All reptiles evolved from an amphibian ancestor around 320 million years ago. The first reptiles were called amniotes and looked just like small lizards.
The oldest known reptile is the Hylonomus. It was a lizard about 8 inches (20 centimeters) long and had small, sharp teeth.
The first reptiles were anapsids, having only three holes in their skulls – one for each eye and one for the nose. Shortly after reptiles appeared, they became separated into two branches – synapsids, who had five holes in their skulls, and sauropsids. Sauropsids were further divided into two groups, one of which consisted of the diapsids, who had seven holes in their skulls.
Anapsid skull by David Stang
During the Permian period, about 300 to 250 million years ago, diapsids became divided into two groups as well – the archosaurs, which are made up of the dinosaurs and crocodiles and the lepidosaurs, made up of tuataras, snakes and lizards.
The oldest known lizard is the Tikiguania estesi, which appeared roughly 220 million years ago. Its fossils were found in India.
Lizards smell with their tongues which is why they often stick their tongues out. Each time a lizard sticks out its tongue, it gathers the scent particles in the air. Then, when their tongues go back inside their mouths, these particles go to a special organ at the roof of the mouth called Jacobson’s organ which helps process the scent.
Monitor lizard in the Frankfurt Zoo by Bukephalos
Most lizards have long, flexible tongues, although the exact length varies per species. Some tongues are fork-shaped while others are rounded or club-shaped.
Not all lizards have legs, and those that do have different kinds of legs and feet depending on where they live. Lizards that live on the ground, for example, have short legs and large feet with sharp claws. Lizards that live on trees have particularly long toes with curved claws, while lizards that live in the water have webbed feet.
Most lizards can easily stick to any surface, even hanging upside down! This is because they have special pads at the bottom of their feet that act like suction cups.
Lizard walking on window – 1 by Alex Ford
Lizards rely mostly on their sight to hunt and move around. As a result, they have good vision and are particularly good at seeing colors.
Most lizards have eyelids and therefore can blink, although you’ll have to look very closely to observe this. Like us, they can move their eyes around, which is one thing that makes them different from snakes.
All lizards have sharp, pointed teeth, although sometimes they may be too small to see. Each time a lizard’s tooth falls out, another one quickly grows in its place so the lizard can continue feeding and protecting itself.
Bitten by Werwin15
Lizards have no external ears, only visible ear openings with their eardrums hidden just below their skin. They can hear better than snakes, though not as well as we do.
A lizard never stops growing, but its skin does. Because of this, lizards regularly shed their skin in flakes.
Lizards are common prey for larger animals, so it is no wonder they have developed various mechanisms to hide and defend themselves, or to escape when caught. Some lizards have colors that allow them to blend in easily with their environment while others can display bright colors when threatened.
One common escape tactic among lizards is shedding their tail. This process is called autotomy.
lizard regenerating it’s tail after caudal autotomy by 外国人-君
The moment a lizard is caught by a predator or feels seriously threatened, it sheds its tail, which continues to wriggle to confuse and distract the predator, giving the lizard time to run to safety. Over the next few weeks, the lizard grows its tail back, though it will only consist of skin and cartilage, and no bone.
Some lizards have thick, sharp spikes to protect themselves. Some of these lizards can even roll into a ball to protect their soft areas.
Two lizard species are considered venomous – the Gila monster and the Mexican beaded lizard. Although their venom is not strong enough to kill, it can cause a lot of discomfort, particularly pain, nausea and difficulty breathing.
Mexican beaded lizards, at the Buffalo Zoo by Davepape
Girdled lizards quickly retreat into cracks when threatened. Once there, they are able to expand their bodies so that the predator cannot pry them out.
Four species of horned lizards can squirt blood out of their eyes, which can travel a distance of up to 4 feet! This startles or confuses the predator, allowing them to escape.
Some lizards are carnivorous, eating insects like crickets, flies and grasshoppers, or eating worms, smaller lizards, birds and even small mammals. Some lizards are herbivorous, eating only leaves, fruits and flowers. Some are omnivorous, eating both plants and other animals.
Lizard (b)eats dragonfly. by Amy Spreitzer Windsor
Although lizards have teeth, they do not chew their food. Instead, they grip their prey until it stops struggling, and they swallow it whole.
Lizards have a powerful digestive system, with many enzymes in their stomach to break down food. Because they are cold-blooded, the pace of their digestion depends on the temperature. They can digest their food quickly when it’s warm but slowly when it’s cold.
There are two types of lizards, depending on how they reproduce. Oviparous lizards lay soft-shelled eggs, which can be as few as five to as many as a hundred. Most lizard eggs hatch between three weeks to three months, though the exact incubation period depends on the temperature.
lizard laying eggs by unkle_sam
Viviparous lizards have live, fully-developed young. Some care for their young while others leave them to fend on their own.
Viviparous lizard from Kanhangad, Kasargod, Kerala, India by Vaikoovery
Like other animals, female lizards release a special scent when they are ready to mate. Male lizards use various methods to win a female over, including changing colors and bobbing their head.
Most lizards do not mate for life, changing mates with each season, and some even have several mates each season. The time and frequency of the mating season varies per species.
Agamas are the most common lizards in Africa, where they have more than 35 species. They eat insects, have long tails and range in size from 5 to 15 inches (12 to 39 centimeters).
Agama Lizard by Charlesjsharp
Agamas live in groups, composed of one dominant male and six to seven females. Other males in the area often challenge the dominant male so fights can break out, with the males bobbing their heads, threatening each other with open jaws and lashing out with their tails.
The common agama is also known as the ‘rainbow lizard’ because dominant males of this species can turn bright orange and blue during the breeding season. Outside of the breeding season, they are dull brown just like the females.
Dominant males of the peninsular rock agama species also change colors. During breeding season, they turn from pale brown to bright red or yellow and black. Peninsular rock agamas have the unique ability to flatten themselves when basking on rocks, especially when birds are flying overhead, resulting in better camouflage.
Rock Agama by Mikhail Esteves
Basilisks are large lizards found in Mexico, Central America and South America. They are also known as ‘Jesus Christ lizards’ because of their ability to run on water, usually on their hind feet. Adults can run for nearly 15 feet (5 meters) before sinking into the water and swimming away while juveniles can run for over 60 feet (18 meters).
Green Basilisk by cuatrok77
When there is no water nearby, basilisks escape from predators by burrowing into the sand. Their nostrils are surrounded by a special ring of muscle, preventing sand from getting inside their noses.
Basilisks are named after the creature from Greek mythology which had the head of a rooster, the body of a lion and the tail of a snake. According to legend, it could cause death with a single glance and left a trail of deadly venom wherever it went.
The common basilisk is the largest basilisk species, able to grow over 3 feet (1 meter) long. Hatchlings are only 2 to 3 inches (5 to 8 centimeters) long and protect themselves by staying motionless for long periods of time.
Common Basilisk, Manual Antonio, Costa Rica by The Rambling Man
The plumed basilisk is the most colorful of the basilisks. Males are a bright shade of green with tiny blue and black spots and have three crests, while females are mint green and have only one crest.
Chameleons are colorful, crested lizards that can be found all over the world, comprised of roughly 160 species. Contrary to popular belief, not all chameleons can change color to match their environment but those that do can pull the act off impressively.
Chameleon by Oliver Ruhm
Chameleons have amazing eyes. Their upper and lower eyelids are joined, leaving only a narrow slit for them to see through. In spite of this, they can see better than most reptiles and can even move each eye independently to look in different directions at the same time.
Chameleons have some of the longest tongues among lizards, with smaller chameleons able to project their tongues longer than larger ones. They use their tongues to catch prey and can do so very fast – in just 3 milliseconds.
Most chameleons are oviparous. The Jackson’s chameleon, however, is ovoviparous, which means its young are developed inside eggs but these eggs remain inside the mother’s body until they are ready to hatch.
Jackson’s Chameleon, three-horned chameleon by Jeff
The Brookesia micra, which can be found in Madagascar, is the smallest known chameleon species and one of the world’s smallest lizard. It can only grow up to 1 inch (3 centimeters) long.
The common chameleon is an example of a chameleon that can change color, usually from yellow to green, brown or black. When caught, it often turns dark brown or black. Adult common chameleons eat mostly insects but will also eat fruits and even young chameleons!
Panther chameleons are the most colorful chameleons, although the exact coloration varies depending on where they live. Some are mostly green with red, purple and blue markings while others are mostly red or mostly blue. Like other lizards, the males are more vibrantly colored than the females.
Panther Chameleon at Zürich Zoo, Switzerland. by Marc Staub
The common lizard or viviparous lizard is the only lizard in its genus and can be found in many parts of Eurasia, particularly in the northern parts. In fact, it is the northernmost of all lizards.
Common Lizards by David Evans
As its other name, viviparous, suggests, the common lizard gives birth to live young, which is an adaptation to a cool climate. The female carries her young for about three months and then cares for them for a short time after they are born.
The frill-necked lizard or frilled lizard is also the only lizard in its genus and is found mainly in Australia and New Guinea. It gets its name from the large flap of skin around its neck which it spreads out when it is frightened.
Frill-necked lizard by Miklos Schiberna
Apart from spreading its neck frill, the frill-necked lizard also opens its mouth when it is threatened, displays its bright orange scales, raises its body and sometimes its tail. The same display is used during courtship.
Frill-necked lizards spend most of their time on trees but can also hunt on the ground. Like basilisks, they can run away on their hind feet at full speed, falling forward when they stop.
Geckos comprise the majority of lizards – there are about 1,600 species of them scattered throughout the world, particularly in areas with a warm climate. They are among the most colorful and most interesting lizards in the world.
This a Gecko by David Torcivia
Geckos are the only lizards that cannot blink. Instead, they have a transparent membrane covering each eye. They often lick this membrane in order to keep their eyes clean and moist.
Geckos are also the only lizards with vocal cords. As a result, they can make chirping sounds which they use to communicate with each other.
Geckos are among the most adhesive lizards, sticking to just about any surface. Some are even able to hang from ceilings with just one foot. Recent research shows that geckos have special glands on their feet which absorb or excrete liquid for maximum adherence.
Not all geckos have adhesive toe pads, though. The leopard gecko is one example of a gecko which cannot cling to glass, which is one of the reasons why it is the most common gecko kept as a pet.
Afghan Leopard Gecko by Brandon Downey
The tokay gecko is a nocturnal gecko found in Southeast Asia, which is known for its loud mating calls. They are commonly found in the walls and ceilings of human homes and are often feared by those who hear them because of the belief that once they stick to human skin, they are very difficult to remove.
The mourning gecko is one example of a lizard that is asexual. All mourning geckos are females and they are able to produce eggs on their own.
Some geckos have webbing which they spread out when they jump, controlling their fall so that they end up landing softly. They are known as flying geckos or parachute geckos.
The Virgin Islands dwarf gecko and the dwarf gecko are the two smallest lizards in the world, measuring only 0.07 inches (18 millimeters) long from snout to tail tip and weighing only 5 thousandths of an ounce (0.15 grams)!
A dwarf yellow-headed gecko by Muhammad Mahdi Karim
The kawekaweau (say “cah-way-cah-way-ow”), or Delcourt’s giant gecko, was the largest gecko to have ever lived, growing up to 23 inches (60 centimeters) long. It is now believed to be extinct.
The Leach’s giant gecko is currently the largest gecko. It is 14 inches (36 centimeters) long and eats insects and fruits as well as small lizards and mice.
The Gila monster is one of only two species of venomous lizards. It is a heavy, sluggish lizard found in the United States and Mexico.
Gila monsters spend most of their time burrowing underground but are active in the mornings during the dry season and on warm summer nights. They eat rarely – only up to ten times a year in the wild! – because of their slow metabolism.
Gila monster by Arpingstone
Gila monsters particularly love to eat bird and reptile eggs. Their sense of smell is so keen that they can smell eggs buried six inches deep in the ground and follow a trail where an egg has rolled.
Gila monsters produce their venom in the salivary glands of their lower jaw and hatchlings are able to do so as soon as they emerge from their eggs. Their venom is as toxic as that produced by the coral snake but since they only produce very small amounts, the venom is hardly fatal.
Glass lizards are sometimes called glass snakes because they look like snakes but they are, in fact, lizards. They get their name from the fact that they can easily break their tail, which breaks off further into smaller pieces like shattered glass.
Eastern Glass Lizard at Airlie Gardens, Wilmington, NC by NatalieK
Horned lizards are sometimes called horned toads but they are truly lizards, only with rounded bodies. They are so named because of the bony horns on their heads, which they straighten when a predator or human attempts to pick them up by the head or neck.
Photo of the Regal Horned Lizard by Room237
Horned lizards are capable of puffing up their bodies. This makes their spikes stand up so that they look sharper, making them look harder to swallow.
Iguanas are among the largest lizards, able to grow up to 5 or 6 feet (2 meters).
Iguanas have a ‘third eye’ on the top of their heads called a parietal eye, which can detect light and help the iguana in regulating its temperature.
Iguana iguana – The Green Iguana by Daniel Davis
The green iguana, or common iguana, is the more common of the two iguana species and is often kept as a pet, though it is not recommended for beginners. In spite of its name, it comes in different colors, including purple and pink.
Green iguanas have long spines on their backs and whip-like tails that can deliver painful strikes. They also have very sharp teeth that can cut through human skin.
Monitor lizards are large, carnivorous lizards known for having long necks and powerful tails. Compared to most lizards, they are known to have a high metabolic rate. They are also known to have great stamina and can breathe easily even when sprinting.
Monitor Lizard, Sungei Buloh Wetlands Reserve, Singapore by yeowatzup
Monitor lizards are known to be intelligent, with some seemingly able to count. Those kept at zoos also show distinct personalities.
The short-tailed monitor is the smallest monitor lizard, only growing up to 9 inches (25 centimeters) long. It can be found in the deserts of Australia.
The Komodo dragon is the largest monitor lizard and the largest of all the lizards. It can grow up to 10 feet (3 meters) long and weigh as much as 150 pounds (70 kilograms).
A Komodo dragon sticks out his tongue at the Cincinnati Zoo by Mark Dumont
The Komodo dragon has 60 saw-like teeth, each about 1 inch (3 centimeters) long. These teeth are mostly covered in gums which open and bleed when they eat, allowing plenty of bacteria to thrive in its mouth. All the bacteria it stores in its mouth means a Komodo dragon’s bite can cause deadly infections.
Komodo dragons have recently been found to be venomous. The venom is subtle – it acts together with the bacteria in the dragon’s mouth to poison the blood of the victim, lowering the blood pressure and leading to shock and unconsciousness.
Komodo dragons eat mostly carrion but will not hesitate to take live prey, such as smaller lizards, including smaller Komodo dragons, birds, monkeys, wild boars, goats and even water buffaloes. They knock down their prey with their tails and then start tearing off large chunks of flesh with their teeth.
Young Komodo Dragon feeding at a water buffalo corpse on Rinca by Mats Stafseng Einarsen
Some Komodo dragons in captivity have been known to lay and hatch eggs even when there is no male around! The hatchlings produced are all male, and so this ability is believed to be an adaptation of the Komodo dragon for survival.
Skinks are not considered true lizards but are classified as lizards just the same. With about 1,500 species, they are the most diverse family of lizards.
Indian Skink, Saap Surli by Desktopwallpapers
Skinks have no pronounced neck and have short legs, some having no legs at all. They also have long tails which they can shed like other lizards, and transparent lower eyelids, allowing them to see even with their eyes closed.
Skinks love to dig and burrow. They do this to escape predators and also to cool themselves down during hot days.
The Florida sand skink looks almost like a snake, though if you take a closer look, you will find that it has tiny legs – the forelegs with only one toe and the hind legs with just two. This body shape enables them to ‘swim’ under the sand where it spends most of its life.
Blue Tongued Skink by Conor Lawless
The green green-blooded skink is one of five species of skink with green blood, which is caused by high levels of bile pigment called biliverdin. The levels of this pigment are so high, in fact, that the blood of this skink is deadly to other animals.
Blue-tongued skinks are best known for displaying their blue tongues while hissing when threatened, trying to trick their enemies into thinking they are poisonous. If the display does not work, they can run very fast, their slippery scales and detachable tails helping them to escape.
The thorny devil, or thorny dragon, is the only lizard found in the genus Moloch and can be found only in Australia. Its color is the same as the desert sand, turning paler in warm weather and darker in cold.
Thorny devil by chem7
Thorny devils have two heads. Well, not really! They have a false head on their backs which they present to enemies when threatened.
Thorny devils do not drink water like most animals. Instead, they get their fluids from the ants they eat. They can also suck up the dew that forms on their skin at night.
Worm lizards are lizards belonging to the group Amphisbaena. Amphisbaena is also the name of a creature in Greek mythology which was an ant-eating serpent with heads at both ends of its body.
Pink-tailed Worm-lizard by Matt
There are over 180 species of worm lizards, and except for the ajolotes who have a pair of forelegs, all of them are legless, hence their name. They are usually pink and have ring-like scales, making them look just like earthworms.
There are over 230 species of whiptail lizards in the world today. They are also called teiids and have rectangular scales and a fork-like tongue like a snake’s.
Bonaire whiptail lizard by Paul Asman
Some whiptail lizards are called tegus. They resemble monitor lizards and are found in Central and South America.
Some kinds of whiptail lizards are all female, yet are able to successfully reproduce. They simulate mating behavior, with one female lying on top of the other, after which both females lay eggs.
The fear of lizards is a long word called scoliodentosaurophobia. If you say it slow you can say the whole thing: “sko-lee-oh-dent-oh-soar-oh-fo-bee-ah”. It is one of the most common phobias in the world and is found to be especially common among women.
Because you love looking at other people’s pets by Justin Baeder
Of all the lizards, only the Komodo Dragon has been known to attack, kill and eat humans, perhaps because it is the only one big and powerful enough to do so. In 2007, an eight-year-old boy was killed by a Komodo Dragon while playing with friends and in 2009, a thirty-one-year-old man was killed while picking apples.
Lizards are one of the most commonly kept pet reptiles. Geckos such as the leopard gecko and the crested gecko are particularly common because they are easy to care for.
The tuatara is not a lizard even though it looks like one. It belongs to a separate order of lizards which flourished roughly 200 million years ago.
Tuatara by Sid Mosdell
Because lizards cannot produce their own body heat, they love to bask in the sun. Unfortunately, this can make them easy prey.
Most lizards shed their skin in small pieces but alligator lizards shed their skin all at the same time in one piece, just like a snake.
Some lizards look like snakes. However, you can easily tell a lizard apart from its snake by its moveable eyes and its small ear openings.
Beady eye by Paul Albertella
The most primitive part of the human brain is called the lizard brain, which has about the same capacity as – you guessed it – a lizard’s brain. It is mainly responsible for the fight, flight or freeze response, as well as telling us which items are edible and which are not.
Photo01 Lizard by Mohamed Malik cc2.0
Photo02 Lizards in our backyard by Oleg Shpyrko cc2.0
Photo03 Lizard in Water by Chris Williamson cc2.0
Photo04 Some Big Lizard! by Yu Ting Lim cc2.0
Photo05 Anapsid skull by David Stang cc3.0
Photo06 Monitor lizard in the Frankfurt Zoo by Bukephalos
Photo07 Lizard walking on window – 1 by Alex Ford cc2.0
Photo08 Bitten by Werwin15 cc2.0
Photo09 lizard regenerating it’s tail after caudal autotomy by ???-? cc2.0
Photo10 Mexican beaded lizards, at the Buffalo Zoo by Davepape
Photo11 Lizard (b)eats dragonfly. by Amy Spreitzer Windsor cc2.0
Photo12 lizard laying eggs by unkle_sam cc2.0
Photo13 Viviparous lizard from Kanhangad, Kasargod, Kerala, India by Vaikoovery cc3.0
Photo14 Agama Lizard by Charlesjsharp cc3.0
Photo15 Rock Agama by Mikhail Esteves cc2.0
Photo16 GREEN BASILISK by cuatrok77 cc2.0
Photo17 Common Basilisk. Photo taken in Manual Antonio, Costa Rica by The Rambling Man cc3.0
Photo18 Chameleon by Oliver Ruhm cc2.0
Photo19 Jackson’s Chameleon, three-horned chameleon by Jeff cc2.0
Photo20 Panther Chameleon at Zürich Zoo, Switzerland. by Marc Staub cc2.0
Photo21 Common Lizards by David Evans cc2.0
Photo22 Frill-necked lizard by Miklos Schiberna
Photo23 This a Gecko by David Torcivia cc2.0
Photo24 Afghan Leopard Gecko by Brandon Downey cc2.0
Photo25 A dwarf yellow-headed gecko by Muhammad Mahdi Karim cc1.2
Photo26 Gila monster by Arpingstone
Photo27 Eastern Glass Lizard at Airlie Gardens, Wilmington, NC by NatalieK cc3.0
Photo28 Photo of the Regal Horned Lizard by Room237 cc3.0
Photo29 Iguana iguana – The Green Iguana by Daniel Davis cc2.0
Photo30 Monitor Lizard, Sungei Buloh Wetlands Reserve, Singapore by yeowatzup cc2.0
Photo31 A Komodo dragon sticks out his tongue at the Cincinnati Zoo by Mark Dumont cc2.0
Photo32 Young Komodo Dragon feeding at a water buffalo corpse on Rinca by Mats Stafseng Einarsen cc3.0
Photo33 Indian Skink , Saap Surli by Desktopwallpapers cc3.0
Photo34 BlueTonguedSkink by Conor Lawless cc2.0
Photo35 Thorny devil by chem7 cc2.0
Photo36 Pink-tailed Worm-lizard by Matt cc2.0
Photo37 Bonaire whiptail lizard by Paul Asman cc2.0
Photo38 Because you love looking at other people’s pets by Justin Baeder cc2.0
Photo39 Tuatara by Sid Mosdell cc2.0
Photo40 Beady eye by Paul Albertella cc2.0