Lizards are a widespread group of squamate reptiles, with over 6,000 species,[1] ranging across all continents except Antarctica, as well as most oceanic island chains. The group is paraphyletic as it excludes the snakes and Amphisbaenia; some lizards are more closely related to these two excluded groups than they are to other lizards. Lizards range in size from chameleons and geckos a few centimeters long to the 3 meter long Komodo dragon.

Most lizards are quadrupedal, running with a strong side-to-side motion. Others are legless, and have long snake-like bodies. Some such as the forest-dwelling Draco lizards are able to glide. They are often territorial, the males fighting off other males and signalling, often with brightly colours, to attract mates and to intimidate rivals. Lizards are mainly carnivorous, often being sit-and-wait predators; many smaller species eat insects, while the Komodo eats mammals as big as water buffalo.

Lizards make use of a variety of antipredator adaptations, including venom, camouflage, reflex bleeding, and the ability to sacrifice and regrow their tails.

Temporal range: Early JurassicHolocene, 199–0 Ma
Possible Late Triassic record
Clockwise from top left: veiled chameleon (Chamaeleo calyptratus), rock monitor (Varanus albigularis), common blue-tongued skink (Tiliqua scincoides), Italian wall lizard (Podarcis sicula), giant leaf-tailed gecko (Uroplatus fimbriatus), and legless lizard (Anelytropsis papillosus)
Clockwise from top left: veiled chameleon (Chamaeleo calyptratus), rock monitor (Varanus albigularis), common blue-tongued skink (Tiliqua scincoides), Italian wall lizard (Podarcis sicula), giant leaf-tailed gecko (Uroplatus fimbriatus), and legless lizard (Anelytropsis papillosus)
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Superorder: Lepidosauria
Order: Squamata

Many, see text

Groups included
Range of the lizards, all species
Range of the lizards, all species
Cladistically included but traditionally excluded taxa

Sauria Macartney, 1802


Largest and smallest

The adult length of species within the suborder ranges from a few centimeters for chameleons such as Brookesia micra and geckos such as Sphaerodactylus ariasae[2] to nearly 3 m (9.8 ft) in the case of the largest living varanid lizard, the Komodo dragon.[3] Most lizards are fairly small animals.

Distinguishing features

Lacertae skin
Skin of Lacerta agilis, showing overlapping scales made of keratin

Lizards typically have four legs, feet and external ears, though some are legless, while snakes lack these characteristics. Lizards and snakes share a movable quadrate bone, distinguishing them from the rhynchocephalians, which have more rigid diapsid skulls [4]. Some lizards such as chameleons have prehensile tails, assisting them in climbing among vegetation.[5]

As in other reptiles, the skin of lizards is covered in overlapping scales made of keratin. This provides protection from the environment and reduces water loss through evaporation. This adaptation enables lizards to thrive in some of the driest deserts on earth. The skin is tough and leathery, and is shed (sloughed) as the animal grows. Unlike snakes which shed the skin in a single piece, lizards slough their skin in several pieces. The scales may be modified into spines for display or protection, and some species have bone osteoderms underneath the scales.[5][6]

Red Tegu Skull
Red tegu (Tupinambis rufescens) skull, showing teeth of differing types

The dentitions of lizards reflect their wide range of diets, including carnivorous, insectivorous, omnivorous, herbivorous, nectivorous, and molluscivorous. Species typically have uniform teeth suited to their diet, but several species have variable teeth, such as cutting teeth in the front of the jaws and crushing teeth in the rear. Most species are pleurodont, though agamids and chameleons are acrodont.[7][5]

The tongue can be extended outside the mouth, and is often long. In the beaded lizards, whiptails and monitor lizards, the tongue is forked and used mainly or exclusively to sense the environment, continually flicking out to sample the environment, and back to transfer molecules to the vomeronasal organ responsible for chemosensation, analogous to but different from smell or taste. In geckos, the tongue is used to lick the eyes clean: they have no eyelids. Chameleons have very long sticky tongues which can be extended rapidly to catch their insect prey.[5]

Three lineages, the geckos, anoles, and chameleons, have modified the scales under their toes to form adhesive pads, highly prominent in the first two groups. The pads are composed of millions of tiny setae (hair-like structures) which fit closely to the substrate to adhere using van der Waals forces; no liquid adhesive is needed.[8] In addition, the toes of chameleons are divided into two opposed groups on each foot (zygodactyly), enabling them to perch on branches as birds do.[a][5]



Gecko foot on glass
Adhesive pads enable geckos to climb vertically.

Aside from legless lizards, most lizards are quadrupedal and move using gaits with alternating movement of the right and left limbs with substantial body bending. This body bending prevents significant respiration during movement, limiting their endurance, in a mechanism called Carrier's constraint. Several species can run bipedally,[9] and a few can prop themselves up on their hindlimbs and tail while stationary. Several small species such as those in the genus Draco can glide: some can attain a distance of 60 metres (200 feet), losing 10 metres (33 feet) in height.[10] Some species, like geckos and chameleons, adhere to vertical surfaces including glass and ceilings.[8] Some species, like the common basilisk, can run across water.[11]


Lizards make use of their senses of sight, touch, olfaction and hearing like other vertebrates. The balance of these varies with the habitat of different species; for instance, skinks that live largely covered by loose soil rely heavily on olfaction and touch, while geckos depend largely on acute vision for their ability to hunt and to evaluate the distance to their prey before striking. Monitor lizards have acute vision, hearing, and olfactory senses. Some lizards make unusual use of their sense organs: chameleons can steer their eyes in different directions, sometimes providing non-overlapping fields of view, such as forwards and backwards at once. Lizards lack external ears, having instead a circular opening in which the tympanic membrane (eardrum) can be seen. Many species rely on hearing for early warning of predators, and flee at the slightest sound.[12]

Nile Monitor (Varanus niloticus) (16545024096)
Nile monitor using its tongue for smell

As in snakes and many mammals, all lizards have a specialised olfactory system, the vomeronasal organ, used to detect pheromones. Monitor lizards transfer scent from the tip of their tongue to the organ; the tongue is used only for this information-gathering purpose, and is not involved in manipulating food.[13][12]

Bearded Dragon Skeleton
Skeleton of bearded dragon (pogona sp.) on display at the Museum of Osteology.

Some lizards, particularly iguanas, have retained a photosensory organ on the top of their heads called the parietal eye, a basal ("primitive") feature also present in the tuatara. This "eye" has only a rudimentary retina and lens and cannot form images, but is sensitive to changes in light and dark and can detect movement. This helps them detect predators stalking it from above.[14]


AZ Gila Monster 02
Some lizards including the gila monster are venomous.

Until 2006 it was thought that among lizards, only the Gila monster and the Mexican beaded lizard were venomous. However, several species of monitor lizards, including the Komodo dragon, produce powerful venom in their oral glands. Lace monitor venom, for instance, causes swift loss of consciousness and extensive bleeding through its pharmacological effects, both lowering blood pressure and preventing blood clotting. Nine classes of toxin known from snakes are produced by lizards. The range of actions provides the potential for new medicinal drugs based on lizard venom proteins.[15][16]

Genes associated with venom toxins have been found in the salivary glands on a wide range of lizards, including species traditionally thought of as non-venomous, such as iguanas and bearded dragons. This suggests that these genes evolved in the common ancestor of lizards and snakes, some 200 million years ago (forming a single clade, the Toxicofera).[15] However, most of these putative venom genes were "housekeeping genes" found in all cells and tissues, including skin and cloacal scent glands. The genes in question may thus be evolutionary precursors of venom genes.[17]


Recent studies (2013 and 2014) on the lung anatomy of the savannah monitor and green iguana found them to have a unidirectional airflow system, which involves the air moving in a loop through the lungs when breathing. This was previously thought to only exist in the archosaurs (crocodilians and birds). This may be evidence that unidirectional airflow is an ancestral trait in diapsids.[18][19]

Reproduction and lifecycle

Trachylepis maculilabris mating
Trachylepis maculilabris skinks mating

As with all amniotes, lizards rely on internal fertilisation and copulation involves the male inserting one of his hemipenes into the female's cloaca.[20] The majority of species are oviparous (egg laying). The female deposits the eggs in a protective structure like a nest or crevice or simply on the ground.[21] Depending on the species, clutch size can vary from 4–5 percent of the females body weight to 40–50 percent and clutches range from one or a few large eggs to dozens of small ones.[22]

EasternFenceLizard Egg
Two pictures taken on an eastern fence lizard egg and layered onto one image.

In most lizards, the eggs have leathery shells to allow for the exchange of water, although more arid-living species have calcified shells to retain water. Inside the eggs, the embryos use nutrients from the yolk. Parental care is uncommon and the female usually abandons the eggs after laying them. Brooding and protection of eggs does occur in some species. The female prairie skink uses respiratory water loss to maintain the humidity of the eggs which facilitates embryonic development. In lace monitors, the young hatch close to 300 days, and the female returns to help them escape the termite mound were the eggs were laid.[21]

Around 20 percent of lizard species reproduce via viviparity (live birth). This is particularly common in Anguimorphs. Viviparous species give birth to relatively developed young which look like miniature adults. Embryos are nourished via a placenta-like structure.[23] A minority of lizards have parthenogenesis (reproduction from unfertilised eggs). These species consist of all females who reproduce asexually with no need for males. This is known in occur in various species of whiptail lizards.[24] Parthenogenesis was also recorded in species that normally reproduce sexually. A captive female Komodo dragon produced a clutch of eggs, despite being separated from males for over two years.[25]

Sex determination in lizards can be temperature-dependent. The temperature of the eggs' micro-environment can determine the sex of the hatched young: low temperature incubation produces more females while higher temperatures produce more males. However, some lizards have sex chromosomes and both male heterogamety (XY and XXY) and female heterogamety (ZW) occur.[24]


Diurnality and thermoregulation

The majority of lizard species are active during the day,[26] though some are active at night, notably geckos. As ectotherms, lizards have a limited ability to regulate their body temperature, and must seek out and bask in sunlight to gain enough heat to become fully active.[27]


Fighting Sand lizards (Lacerta agilis) 4295304
Fighting male sand lizards

Most social interactions among lizards are between breeding individuals.[26] Territoriality is common and is correlated with species that use sit-and-wait hunting strategies. Males establish and maintain territories that contain resources which attract females and which they defend from other males. Important resources include basking, feeding, and nesting sites as well as refuges from predators. The habitat of a species affects the structure of territories, for example, rock lizards have territories atop rocky outcrops.[28] Some species may aggregate in groups, enhancing vigilance and lessening the risk of predation for individuals, particularly for juveniles.[29] Agonistic behaviour typically occurs between sexually mature males over territory or mates and may involve displays, posturing, chasing, grappling and biting.[28]

Green anole
A Green Anole (Anolis carolinensis) signalling with its extended dewlap


Lizards signal both to attract mates and to intimidate rivals. Visual displays include body postures and inflation, push-ups, bright colours, mouth gapings and tail waggings. Male anoles and iguanas have dewlaps or skin flaps which come in various sizes, colours and patterns and the expansion of the dewlap as well as head-bobs and body movements add to the visual signals.[30][5] Some species have deep blue dewlaps and communicate with ultraviolet signals.[26] Blue-tongued skinks will flash their tongues as a threat display.[31] Chameleons are known to change their complex colour patterns when communicating, particularly during agonistic encounters. They tend to show brighter colours when displaying aggression[32] and darker colours when they submit or "give up".[33]

Several gecko species are brightly coloured; some species tilt their bodies to display their coloration. In certain species, brightly coloured males turn dull when not in the presence of rivals or females. While it is usually males that display, in some species females also use such communication. In the bronze anole, head-bobs are a common form of communication among females, the speed and frequency varying with age and territorial status. Chemical cues or pheromones are also important in communication. Males typically direct signals at rivals, while females direct them at potential mates. Lizards may be able to recognise individuals of the same species by their scent.[30]

Acoustic communication is less common in lizards. Hissing, a typical reptilian sound, is mostly produced by larger species as part of a threat display, accompanying gaping jaws. Some groups, particularly geckos, snake-lizards, and some iguanids, can produce more complex sounds and vocal apparatuses have independently evolved in different groups. These sounds are used for courtship, territorial defense and in distress, and include clicks, squeaks, barks and growls. The mating call of the male tokay gecko is heard as "tokay-tokay!".[31][30][34] Tactile communication involves individuals rubbing against each other, either in courtship or in aggression.[30] Some chameleon species communicate with one another by vibrating the substrate that they are standing on, such as a tree branch or leaf.[35]


Lizard namely Oriental Garden Lizard
Lizard in tree. Many species are tree-dwelling

Distribution and habitat

Lizards are found worldwide, excluding the far north and Antarctica, and some islands. They can be found in elevations from sea level to 5,000 m (16,000 ft). They prefer warmer, tropical climates but are adaptable and can live in all but the most extreme environments. Lizards also exploit a number of habitats; most primarily live on the ground, but others may live in rocks, on trees, underground and even in water. The marine iguana is adapted for life in the sea.[5]


The majority of lizard species are predatory and the most common prey items are small, terrestrial invertebrates, particularly insects.[5][36] Many species are sit-and-wait predators though others may be more active foragers.[37] Chameleons prey on numerous insect species, such as beetles, grasshoppers and winged termites as well as spiders. They rely on persistence and ambush to capture these prey. An individual perches on a branch and stays perfectly still, with only its eyes moving. When an insect lands, the chameleon focuses its eyes on the target and slowly moves towards it before projecting its long sticky tongue which, when hauled back, brings the attach prey with it. Geckos feed on crickets, beetles, termites and moths.[5][36]

Termites are an important part of the diets of some species of Autarchoglossa, since, as social insects, they can be found in large numbers in one spot. Ants may form a prominent part of the diet of some lizards, particularly among the lacertas.[5][36] Horned lizards are also well known for specializing on ants. Due to their small size and indigestible chitin, ants must be consumed in large amounts, and ant-eating lizards have larger stomachs than even herbivorous ones.[38] Species of skink and alligator lizards eat snails and their power jaws and molar-like teeth are adapted for breaking the shells.[5][36]

Komodo Dragon Eating Rinca
Young Komodo dragon feeding on a water buffalo carcass
Marine Iguana (Amblyrhynchus cristatus), Galápagos Islands, Ecuador - foraging under water (5755672016)
Marine iguana foraging under water at Galápagos Islands, Ecuador.

Larger species, such as monitor lizards, can feed on larger prey including fish, frogs, birds, mammals and other reptiles. Prey may be swallowed whole and torn into smaller pieces. Both bird and reptile eggs may also be consumed as well. Gila monsters and beaded lizards climb trees to reach both the eggs and young of birds. Despite being venomous, these species rely on their strong jaws to kill prey. Mammalian prey typically consists of rodents and leporids; the Komodo dragon can kill prey as large as water buffalo. Dragons are prolific scavengers, and a single decaying carcass can attract several from 2 km (1.2 mi) away. A 50 kg (110 lb) dragon is capable of consuming a 31 kg (68 lb) carcass in 17 minutes.[36]

Around 2 percent of lizard species, including many iguanids, are herbivores. Adults of these species eat plant parts like flowers, leaves, stems and fruit, while juveniles eat more insects. Plant parts can be hard to digest and as they get closer to adulthood, juvenile iguanas eat faeces from adults to acquire the microflora necessary for their transition to a plant-based diet. Perhaps the most herbivorous species is the marine iguana which dives 15 m (49 ft) to forage for algae, kelp and other marine plants. Some non-herbivorous species supplement their insect diet with fruit, which is easily digested.[5][36]

Antipredator adaptations

The frilled-neck lizard with fully extended frill. The frilled serves to make it look bigger than it actually is.

Lizards have a variety of antipredator adaptations, including running and climbing, venom, camouflage, tail autotomy, and reflex bleeding.


Phrynosoma mcallii
The flat-tail horned lizard's body is flattened and fringed to minimise its shadow.

Lizards exploit a variety of different camouflage methods. Many lizards are disruptively patterned. In some species, such as Aegean wall lizards, individuals vary in colour, and select rocks which best match their own colour to minimise the risk of being detected by predators.[39] The Moorish gecko is able to change colour for camouflage: when a light-coloured gecko is placed on a dark surface, it darkens within an hour to match the environment.[40] The chameleons in general use their ability to change their coloration for signalling rather than camouflage, but some species such as Smith's dwarf chameleon do use active colour change for camouflage purposes.[41]

The flat-tail horned lizard's body is coloured like its desert background, and is flattened and fringed with white scales to minimise its shadow.[42]


A skink tail continuing to move after autotomy

Many lizards, including geckos and skinks, are capable of shedding their tails (autotomy). The detached tail, sometimes brilliantly coloured, continues to writhe after detaching, distracting the predator's attention from the fleeing prey. Lizards partially regenerate their tails over a period of weeks. Some 326 genes are involved in regenerating lizard tails.[43] The fish-scale gecko Geckolepis megalepis sheds patches of skin and scales if grabbed.[44]

Escape, playing dead, reflex bleeding

Many lizards attempt to escape from danger by running to a place of safety;[45][b] for example, wall lizards can run up walls and hide in holes or cracks.[8] Horned lizards adopt differing defences for specific predators. They may play dead to deceive a predator that has caught them; attempt to outrun the rattlesnake, which does not pursue prey; but stay still, relying on their cryptic coloration, for Masticophis whip snakes which can catch even swift prey. If caught, some species such as the greater short-horned lizard puff themselves up, making their bodies hard for a narrow-mouthed predator like a whip snake to swallow. Finally, horned lizards can squirt blood at cat and dog predators from a pouch beneath its eyes, to a distance of about two metres (6.6 feet); the blood tastes foul to these attackers.[47]


Fossil history

The earliest known fossil remains of a lizard belong to the iguanian species Tikiguania estesi, found in the Tiki Formation of India, which dates to the Carnian stage of the Triassic period, about 220 million years ago.[48] However, doubt has been raised over the age of Tikiguania because it is almost indistinguishable from modern agamid lizards. The Tikiguania remains may instead be late Tertiary or Quaternary in age, having been washed into much older Triassic sediments.[49] Lizards are most closely related to the Rhynchocephalia, which appeared in the Late Triassic, so the earliest lizards probably appeared at that time.[49] Mitochondrial phylogenetics suggest that the first lizards evolved in the late Permian. It had been thought on the basis of morphological data that iguanid lizards diverged from other squamates very early on, but molecular evidence contradicts this.[50]



The position of the lizards and other Squamata among the reptiles was studied using fossil evidence by Rainer Schoch and Hans-Dieter Sues in 2015. Lizards form about 60% of the extant non-avian reptiles.[51]


ArchosauromorphaDescription des reptiles nouveaux, ou, Imparfaitement connus de la collection du Muséum d'histoire naturelle et remarques sur la classification et les caractères des reptiles (1852) (Crocodylus moreletii)Meyers grosses Konversations-Lexikon - ein Nachschlagewerk des allgemeinen Wissens (1908) (Antwerpener Breiftaube).jpg


KuehneosauridaeIcarosaurus white background


SquamataZoology of Egypt (1898) (Varanus griseus)

RhynchocephaliaHatteria white background

Pantestudines Psammobates geometricus 1872 white background


Both the snakes and the Amphisbaenia (worm lizards) are clades deep within the Squamata (the smallest clade that contains all the lizards), so "lizard" is paraphyletic.[52] The cladogram is based on genomic analysis by Wiens and colleagues in 2012 and 2016.[53][54] Excluded taxa are shown in upper case on the cladogram.




Diplodactylidae Hoplodactylus pomarii white background

Pygopodidae The zoology of the voyage of the H.M.S. Erebus and Terror (Lialis burtonis)






Phyllodactylidae Phyllodactylus gerrhopygus 1847 - white background

Gekkonidae G gecko 060517 6167 trij (washout)


Scincidae Bilder-Atlas zur wissenschaftlich-populären Naturgeschichte der Wirbelthiere (Plate (24)) Tribolonotus novaeguineae



Gerrhosauridae Gerrhosaurus ocellatus flipped

Cordylidae Illustrations of the zoology of South Africa (Smaug giganteus)


Gymnophthalmidae PZSL1851PlateReptilia06 Cercosaura ocellata

Teiidae Bilder-Atlas zur wissenschaftlich-populären Naturgeschichte der Wirbelthiere (Tupinambis teguixin)


Lacertidae Brockhaus' Konversations-Lexikon (1892) (Lacerta agilis)

AMPHISBAENIA (worm lizards, not usually considered "true lizards") Amphisbaena microcephalum 1847 - white background





Varanidae Zoology of Egypt (1898) (Varanus griseus)


Helodermatidae Gila monster ncd 2012 white background






Anguidae Anguis fragilis (cropped)


Chamaeleonidae Zoology of Egypt (1898) (Chamaeleo calyptratus)

Agamidae Haeckel Lacertilia (Chlamydosaurus kingii)



Iguanidae Stamps of Germany (Berlin) 1977, Cyclura cornuta



Corytophanidae SDC10934 - Basiliscus plumifrons (extracted)








SERPENTES (snakes, not considered to be lizards) Python natalensis Smith 1840 white background


Artistic restoration of a mosasaur, Prognathodon

In the 13th century, lizards were recognized in Europe as part of a broad category of reptiles that consisted of a miscellany of egg-laying creatures, including "snakes, various fantastic monsters, […], assorted amphibians, and worms", as recorded by Vincent of Beauvais in his Mirror of Nature.[55] The seventeenth century saw changes in this loose description. The name Sauria was coined by James Macartney (1802);[56] it was the Latinisation of the French name Sauriens, coined by Alexandre Brongniart (1800) for an order of reptiles in the classification proposed by the author, containing lizards and crocodilians,[57] later discovered not to be each other's closest relatives. Later authors used the term "Sauria" in a more restricted sense, i.e. as a synonym of Lacertilia, a suborder of Squamata that includes all lizards but excludes snakes. This classification is rarely used today because Sauria so-defined is a paraphyletic group. It was defined as a clade by Jacques Gauthier, Arnold G. Kluge and Timothy Rowe (1988) as the group containing the most recent common ancestor of archosaurs and lepidosaurs (the groups containing crocodiles and lizards, as per Mcartney's original definition) and all its descendants.[58] A different definition was formulated by Michael deBraga and Olivier Rieppel (1997), who defined Sauria as the clade containing the most recent common ancestor of Choristodera, Archosauromorpha, Lepidosauromorpha and all their descendants.[59] However, these uses have not gained wide acceptance among specialists.

Suborder Lacertilia (Sauria) – (lizards)

The slowworms, Anguis, are among over twenty groups of lizards that have convergently evolved a legless body plan.[60]


Lizards have frequently evolved convergently, with multiple groups independently developing similar morphology and ecological niches. Anolis ecomorphs have become a model system in evolutionary biology for studying convergence.[61] Limbs have been lost or reduced independently over two dozen times across lizard evolution, including in the Anniellidae, Anguidae, Cordylidae, Dibamidae, Gymnophthalmidae, Pygopodidae, and Scincidae; snakes are just the most famous and species-rich group of Squamata to have followed this path.[60]

Relationship with humans

Most lizard species are harmless to humans. Only the largest lizard species, the Komodo dragon, which reaches 3.3 m (11 ft) in length and weighs up to 166 kg (366 lb), has been known to stalk, attack, and, on occasion, kill humans. An eight-year-old Indonesian boy died from blood loss after an attack in 2007.[62]

Kini iguana
Green iguanas (Iguana iguana), are popular pets.

Numerous species of lizard are kept as pets, including bearded dragons,[63] iguanas, anoles,[64] and geckos (such as the popular leopard gecko).[63]

Lizards appear in myths and folktales around the world. In Australian Aboriginal mythology, Tarrotarro, the lizard god, split the human race into male and female, and gave people the ability to express themselves in art. A lizard king named Mo'o features in Hawaii and other cultures in Polynesia. In the Amazon, the lizard is the king of beasts, while among the Bantu of Africa, the god Unkulunkulu sent a chameleon to tell humans they would live forever, but the chameleon was held up, and another lizard brought a different message, that the time of humanity was limited.[65] A popular legend in Maharashtra tells the tale of how a common Indian monitor, with ropes attached, was used to scale the walls of the fort in the Battle of Sinhagad.[66]

Green iguanas are eaten in Central America, where they are sometimes referred to as "chicken of the tree" after their habit of resting in trees and their supposedly chicken-like taste,[67] while spiny-tailed lizards are eaten in Africa. In North Africa, Uromastyx species are considered dhaab or 'fish of the desert' and eaten by nomadic tribes.[68]

Lizards such as the Gila monster produce toxins with medical applications. Gila toxin reduces plasma glucose; the substance is now synthesised for use in the anti-diabetes drug exenatide (Byetta).[16] Another toxin from Gila monster saliva has been studied for use as an anti-Alzheimer's drug.[69]

Lizards in many cultures share the symbolism of snakes, especially as an emblem of resurrection. This may have derived from their regular moulting. The motif of lizards on Christian candle holders probably alludes to the same symbolism. According to Jack Tresidder, in Egypt and the Classical world they were beneficial emblems, linked with wisdom. In African, Aboriginal and Melanesian folklore they are linked to cultural heroes or ancestral figures.[70]


  1. ^ Chameleon forefeet have groups composed of 3 inner and 2 outer digits; the hindfeet have groups of 2 inner and 3 outer digits.[5]
  2. ^ The BBC's 2016 Planet Earth II showed a sequence of newly-hatched marine iguanas running to the sea past a waiting crowd of racer snakes. It was edited for dramatic effect but the sections were all genuine.[46]


  1. ^ Reptile Database. Retrieved on 2012-04-22
  2. ^ Muir, Hazel (3 December 2001). "Minute gecko matches smallest reptile record". New Scientist.
  3. ^ "The world's top 10 reptiles – in pictures". The Guardian. 5 May 2016.
  4. ^ Evans, Jones; et al. (2011). "Hard tissue anatomy of the cranial joints in Sphenodon (Rhynchocephalia): sutures, kinesis, and skull mechanics". Palaeontologia Electronica. 14(2, 17A): 1–92.
  5. ^ a b c d e f g h i j k l m Bauer, A. M.; Kluge, A. G.; Schuett, G. (2002). "Lizards". In Halliday, T.; Adler, K. (eds.). The Firefly Encyclopedia of Reptiles and Amphibians. Firefly Books. pp. 139–169. ISBN 978-1-55297-613-5.CS1 maint: Multiple names: authors list (link)
  6. ^ Starr, C.; Taggart, R.; Evers, C. (2012). Biology: The Unity and Diversity of Life. Cengage Learning. p. 429. ISBN 978-1111425692.CS1 maint: Multiple names: authors list (link)
  7. ^ Pough; et al. (2002) [1992]. Herpetology (Third ed.). Pearson Prentice Hall.
  8. ^ a b c Spinner, Marlene; et al. (2014). "Subdigital setae of chameleon feet: Friction-enhancing microstructures for a wide range of substrate roughness". Scientific Reports. 4: 5481. Bibcode:2014NatSR...4E5481S. doi:10.1038/srep05481. PMC 4073164. PMID 24970387.
  9. ^ Irschick, D. J.; Jayne, B. C. (1 May 1999). "Comparative three-dimensional kinematics of the hindlimb for high-speed bipedal and quadrupedal locomotion of lizards". Journal of Experimental Biology. 202 (9): 1047–1065. PMID 10101105 – via
  10. ^ Piper, Ross (2007), Extraordinary Animals: An Encyclopedia of Curious and Unusual Animals, Greenwood Press.
  11. ^ Pianka and Vitt, 23–24
  12. ^ a b Wilson, Steve (2012). Australian Lizards: A Natural History. Csiro Publishing. pp. 65–74. ISBN 978-0-643-10642-0.
  13. ^ Frasnelli, J.; et al. (2011). "The vomeronasal organ is not involved in the perception of endogenous odors". Hum. Brain Mapp. 32 (3): 450–60. doi:10.1002/hbm.21035. PMC 3607301. PMID 20578170.
  14. ^ Brames, Henry (2007), "Aspects of Light and Reptile Immunity" (PDF), Iguana: Conservation, Natural History, and Husbandry of Reptiles, 14 (1): 19–23
  15. ^ a b Fry, Bryan G.; et al. (16 November 2005). "Early evolution of the venom system in lizards and snakes". Nature. 439 (7076): 584–588. doi:10.1038/nature04328. PMID 16292255.
  16. ^ a b Casey, Constance (26 April 2013). "Don't Call It a Monster". Slate.
  17. ^ Hargreaves, Adam D.; et al. (2014). "Testing the Toxicofera: Comparative transcriptomics casts doubt on the single, early evolution of the reptile venom system". Toxicon. 92: 140–156. doi:10.1016/j.toxicon.2014.10.004. PMID 25449103.
  18. ^ Schachner, Emma R.; Cieri, Robert L.; Butler, James P.; Farmer, C. G. (2014). "Unidirectional pulmonary airflow patterns in the savannah monitor lizard". Nature. 506 (7488): 367–370. Bibcode:2014Natur.506..367S. doi:10.1038/nature12871. PMID 24336209.CS1 maint: Multiple names: authors list (link)
  19. ^ Robert L.; Craven, Brent A.; Schachner, Emma R.; Farmer, C. G. (2014). "New insight into the evolution of the vertebrate respiratory system and the discovery of unidirectional airflow in iguana lungs". PNAS. 111 (48): 17218–17223. Bibcode:2014PNAS..11117218C. doi:10.1073/pnas.1405088111. PMC 4260542. PMID 25404314.CS1 maint: Multiple names: authors list (link)
  20. ^ Pianka and Vitt, pp. 108.
  21. ^ a b Pianka and Vitt, pp. 115–116.
  22. ^ Pianka and Vitt, pp. 110–111.
  23. ^ Pianka and Vitt, pp. 117–118.
  24. ^ a b Pianka and Vitt, pp. 119.
  25. ^ Morales, Alex (20 December 2006). "Komodo Dragons, World's Largest Lizards, Have Virgin Births". Bloomberg Television. Retrieved 28 March 2008.
  26. ^ a b c Pianka and Vitt, pp. 86.
  27. ^ Pianka and Vitt, pp. 32–37.
  28. ^ a b Pianka and Vitt, pp. 94–106.
  29. ^ Lanham, E. J.; Bull. M. C. (2004). "Enhanced vigilance in groups in Egernia stokesii, a lizard with stable social aggregations". Journal of Zoology. 263 (1): 95–99. doi:10.1017/S0952836904004923.CS1 maint: Multiple names: authors list (link)
  30. ^ a b c d Pianka and Vitt, pp. 87–94.
  31. ^ a b Langley, L. (24 October 2015). "Are Lizards as Silent as They Seem?". Retrieved 9 July 2017.
  32. ^ Ligon, Russell A.; McGraw, Kevin J. (2013). "Chameleons communicate with complex colour changes during contests: different body regions convey different information". Biology Letters. 9 (6): 20130892. doi:10.1098/rsbl.2013.0892. PMC 3871380. PMID 24335271.
  33. ^ Ligon, Russell A (2014). "Defeated chameleons darken dynamically during dyadic disputes to decrease danger from dominants". Behavioral Ecology and Sociobiology. 68 (6): 1007–1017. doi:10.1007/s00265-014-1713-z.
  34. ^ Frankenberg, E.; Werner, Y. L. (1992). "Vocal communication in the Reptilia–facts and questions". 41. Acta Zoologica: 45–62.CS1 maint: Multiple names: authors list (link)
  35. ^ Barnett, K. E.; Cocroft, R. B.; Fleishman, L. J. (1999). "Possible communication by substrate vibration in a chameleon" (PDF). Copeia. 1 (1): 225–228. doi:10.2307/1447408. JSTOR 1447408.CS1 maint: Multiple names: authors list (link)
  36. ^ a b c d e f Pianka and Vitt, pp. 41–51.
  37. ^ Pianka and Vitt, pp. 53–55.
  38. ^ Pianka and Vitt, pp. 162.
  39. ^ Marshall, Kate; Philpot, Kate E.; Stevens, Martin (25 January 2016). "Microhabitat choice in island lizards enhances camouflage against avian predators". Scientific Reports. 6: 19815. Bibcode:2016NatSR...619815M. doi:10.1038/srep19815. PMC 4726299. PMID 26804463.CS1 maint: Multiple names: authors list (link)
  40. ^ Yong, Ed (16 July 2014). "Lizard 'Sees' With Its Skin For Automatic Camouflage". National Geographic.
  41. ^ Stuart-Fox, Devi; Moussalli, Adnan; Whiting, Martin J. (23 August 2008). "Predator-specific camouflage in chameleons". Biology Letters. 4 (4): 326–329. doi:10.1098/rsbl.2008.0173. PMC 2610148. PMID 18492645.
  42. ^ Sherbrooke, WC (2003). Introduction to horned lizards of North America. University of California Press. pp. 117–118. ISBN 978-0-520-22825-2.
  43. ^ Scientists discover how lizards regrow tails, The Independent, August 20, 2014
  44. ^ Scherz, Mark D.; et al. (2017). "Off the scale: a new species of fish-scale gecko (Squamata: Gekkonidae: Geckolepis) with exceptionally large scales". PeerJ. 5: e2955. doi:10.7717/peerj.2955. PMC 5299998. PMID 28194313.
  45. ^ Cooper, William E., Jr. (2010). "Initiation of Escape Behavior by the Texas Horned Lizard (Phrynosoma cornutum)". Herpetologica. 66 (1): 23–30. doi:10.1655/08-075.1.
  46. ^ "From Planet Earth II, a baby iguana is chased by snakes". BBC. 15 November 2016.
  47. ^ Hewitt, Sarah (5 November 2015). "If it has to, a horned lizard can shoot blood from its eyes". BBC.
  48. ^ Datta, P.M. & Ray, S. (2006). "Earliest lizards from the Late Triassic (Carnian) of India". Journal of Vertebrate Paleontology. 26 (4): 95–800. doi:10.1671/0272-4634(2006)26[795:ELFTLT]2.0.CO;2.
  49. ^ a b Hutchinson, M.N.; Skinner, A.; Lee, M.S.Y. (2012). "Tikiguania and the antiquity of squamate reptiles (lizards and snakes)". Biology Letters. 8 (4): 665–9. doi:10.1098/rsbl.2011.1216. PMC 3391445. PMID 22279152.
  50. ^ Kumazawa, Yoshinori (2007). "Mitochondrial genomes from major lizard families suggest their phylogenetic relationships and ancient radiations". Gene. 388 (1–2): 19–26. doi:10.1016/j.gene.2006.09.026. PMID 17118581.
  51. ^ Schoch, Rainer R.; Sues, Hans-Dieter (24 June 2015). "A Middle Triassic stem-turtle and the evolution of the turtle body plan" (PDF). Nature. 523 (7562): 584–587. Bibcode:2015Natur.523..584S. doi:10.1038/nature14472. PMID 26106865. (Subscription required (help)). Cite uses deprecated parameter |subscription= (help)
  52. ^ Reeder, Tod W.; Townsend, Ted M.; Mulcahy, Daniel G.; Noonan, Brice P.; Wood, Perry L.; Sites, Jack W.; Wiens, John J. (2015). "Integrated Analyses Resolve Conflicts over Squamate Reptile Phylogeny and Reveal Unexpected Placements for Fossil Taxa". PLOS ONE. 10 (3): e0118199. Bibcode:2015PLoSO..1018199R. doi:10.1371/journal.pone.0118199. PMC 4372529. PMID 25803280.
  53. ^ Wiens, J. J.; Hutter, C. R.; Mulcahy, D. G.; Noonan, B. P.; Townsend, T. M.; Sites, J. W.; Reeder, T. W. (2012). "Resolving the phylogeny of lizards and snakes (Squamata) with extensive sampling of genes and species". Biology Letters. 8 (6): 1043–1046. doi:10.1098/rsbl.2012.0703. PMC 3497141. PMID 22993238.
  54. ^ Zheng, Yuchi; Wiens, John J. (2016). "Combining phylogenomic and supermatrix approaches, and a time-calibrated phylogeny for squamate reptiles (lizards and snakes) based on 52 genes and 4162 species". Molecular Phylogenetics and Evolution. 94 (Pt B): 537–547. doi:10.1016/j.ympev.2015.10.009. PMID 26475614.
  55. ^ Franklin-Brown, Mary (2012). Reading the world : encyclopedic writing in the scholastic age. Chicago London: The University of Chicago Press. p. 223;377. ISBN 9780226260709.
  56. ^ James Macartney: Table III in: George Cuvier (1802) "Lectures on Comparative Anatomy" (translated by William Ross under the inspection of James Macartney). Vol I. London, Oriental Press, Wilson and Co.
  57. ^ Alexandre Brongniart (1800) "Essai d’une classification naturelle des reptiles. 1ère partie: Etablissement des ordres." Bulletin de la Science. Société Philomathique de Paris 2 (35): 81-82
  58. ^ Gauthier, J. A.; Kluge, A. G.; Rowe, T. (June 1988). "Amniote phylogeny and the importance of fossils". Cladistics. 4 (2): 105–209. doi:10.1111/j.1096-0031.1988.tb00514.x.
  59. ^ Debraga, M. & Rieppel, O. (1997). "Reptile phylogeny and the interrelationships of turtles". Zoological Journal of the Linnean Society. 120 (3): 281–354. doi:10.1111/j.1096-3642.1997.tb01280.x.
  60. ^ a b Brandley, Matthew C.; et al. (August 2008). "Rates And Patterns In The Evolution Of Snake-Like Body Form In Squamate Reptiles: Evidence For Repeated Re-Evolution Of Lost Digits And Long-Term Persistence Of Intermediate Body Forms". Evolution. 62 (8): 2042–2064. doi:10.1111/j.1558-5646.2008.00430.x. PMID 18507743.
  61. ^ Losos, Jonathan B. (1992). "The Evolution of Convergent Structure in Caribbean Anolis Communities". Systematic Biology. 41 (4): 403–420. doi:10.1093/sysbio/41.4.403.
  62. ^ "Komodo dragon kills boy in Indonesia". MSNBC. Retrieved 2011-11-07.
  63. ^ a b Virata, John B. "5 Great Beginner Pet Lizards". Reptiles Magazine. Retrieved 28 May 2017.
  64. ^ McLeod, Lianne. "An Introduction to Green Anoles as Pets". The Spruce. Retrieved 28 May 2017.
  65. ^ Greenberg, Daniel A. (2004). Lizards. Marshall Cavendish. pp. 15–16. ISBN 978-0-7614-1580-0.
  66. ^ Auffenberg, Walter (1994). The Bengal Monitor. University Press of Florida. p. 494. ISBN 978-0-8130-1295-7.
  67. ^ "Referencias culturales - todo iguanas verdes". Archived from the original on 2016-10-26. Retrieved 2018-11-25.
  68. ^ Grzimek, Bernhard. Grzimek's Animal Life Encyclopedia (Second Edition) Vol 7 – Reptiles. (2003) Thomson – Gale. Farmington Hills, Minnesota. Vol Editor – Neil Schlager. ISBN 0-7876-5783-2 (for vol.7). p. 48
  69. ^ "Alzheimer's research seeks out lizards". BBC. 5 April 2002.
  70. ^ Tresidder, Jack (1997). the Hutchinson Dictionary of Symbols. London: Helicon. p. 125. ISBN 978-1-85986-059-5.

General sources

  • Pianka, E. R.; Vitt, L. J. (2003). Lizards: Windows to the Evolution of Diversity. University of California Press. ISBN 978-0-520-23401-7.CS1 maint: Multiple names: authors list (link)

Further reading

  • Behler, John L.; King, F. Wayne (1979). The Audubon Society Field Guide to Reptiles and Amphibians of North America. New York: Alfred A. Knopf. p. 581. ISBN 978-0-394-50824-5.
  • Capula, Massimo; Behler, John L. (1989). Simon & Schuster's Guide to Reptiles and Amphibians of the World. New York: Simon & Schuster. ISBN 978-0-671-69098-4.
  • Cogger, Harold; Zweifel, Richard (1992). Reptiles & Amphibians. Sydney: Weldon Owen. ISBN 978-0-8317-2786-4.
  • Conant, Roger; Collins, Joseph (1991). A Field Guide to Reptiles and Amphibians Eastern/Central North America. Boston, Massachusetts: Houghton Mifflin Company. ISBN 978-0-395-58389-0.
  • Ditmars, Raymond L (1933). Reptiles of the World: The Crocodilians, Lizards, Snakes, Turtles and Tortoises of the Eastern and Western Hemispheres. New York: Macmillan. p. 321.
  • Freiberg, Marcos; Walls, Jerry (1984). The World of Venomous Animals. New Jersey: TFH Publications. ISBN 978-0-87666-567-1.
  • Gibbons, J. Whitfield (1983). Their Blood Runs Cold: Adventures With Reptiles and Amphibians. Alabama: University of Alabama Press. p. 164. ISBN 978-0-8173-0135-4.
  • Greenberg, Daniel A. (2004). Lizards. Marshall Cavendish. ISBN 9780761415800.
  • Rosenfeld, Arthur (1987). Exotic Pets. New York: Simon & Schuster. p. 293. ISBN 978-0671636906.

External links

Gila monster

The Gila monster (Heloderma suspectum, HEE-lə) is a species of venomous lizard native to the southwestern United States and northwestern Mexican state of Sonora. A heavy, typically slow-moving lizard, up to 60 cm (2.0 ft) long, the Gila monster is the only venomous lizard native to the United States and one of only two known species of venomous lizards in North America, the other being its close relative, the Mexican beaded lizard (H. horridum). Although the Gila monster is venomous, its sluggish nature means it represents little threat to humans. However, it has acquired a fearsome reputation, and is sometimes killed despite being protected by state law in Arizona.

Komodo dragon

The Komodo dragon (Varanus komodoensis), also known as the Komodo monitor, is a species of lizard found in the Indonesian islands of Komodo, Rinca, Flores, and Gili Motang. A member of the monitor lizard family Varanidae, it is the largest living species of lizard, growing to a maximum length of 3 metres (10 ft) in rare cases and weighing up to approximately 70 kilograms (150 lb).Their unusually large size has been attributed to island gigantism, since no other carnivorous animals fill the niche on the islands where they live. However, recent research suggests the large size of Komodo dragons may be better understood as representative of a relict population of very large varanid lizards that once lived across Indonesia and Australia, most of which, along with other megafauna, died out after the Pleistocene (as a result of human activity). Fossils very similar to V. komodoensis have been found in Australia dating to greater than 3.8 million years ago, and its body size remained stable on Flores, one of the handful of Indonesian islands where it is currently found, over the last 900,000 years, "a time marked by major faunal turnovers, extinction of the island's megafauna, and the arrival of early hominids by 880 ka [kiloannums]."As a result of their size, these lizards dominate the ecosystems in which they live. Komodo dragons hunt and ambush prey including invertebrates, birds, and mammals. It has been claimed that they have a venomous bite; there are two glands in the lower jaw which secrete several toxic proteins. The biological significance of these proteins is disputed, but the glands have been shown to secrete an anticoagulant. Komodo dragons' group behaviour in hunting is exceptional in the reptile world. The diet of big Komodo dragons mainly consists of Timor deer, though they also eat considerable amounts of carrion. Komodo dragons also occasionally attack humans.Mating begins between May and August, and the eggs are laid in September. About 20 eggs are deposited in abandoned megapode nests or in a self-dug nesting hole. The eggs are incubated for seven to eight months, hatching in April, when insects are most plentiful. Young Komodo dragons are vulnerable and therefore dwell in trees, safe from predators and cannibalistic adults. They take 8 to 9 years to mature, and are estimated to live up to 30 years.Komodo dragons were first recorded by Western scientists in 1910. Their large size and fearsome reputation make them popular zoo exhibits. In the wild, their range has contracted due to human activities, and they are listed as vulnerable by the IUCN. They are protected under Indonesian law, and a national park, Komodo National Park, was founded to aid protection efforts.

Lizard (comics)

The Lizard (Dr. Curtis "Curt" Connors) is a fictional character, a supervillain appearing in American comic books published by Marvel Comics. The character is usually depicted as an enemy of Spider-Man. In 2009, The Lizard was ranked IGN's 62nd Greatest Comic Villain of All Time. In the stories, Dr. Connors was a genetic biologist who researched the ability of certain reptiles to regrow missing limbs, partially to find a way to regenerate his right arm. After a test on himself, he transforms into a violent lizard monster. Though able to revert to his human form, he suffers occasional fits of his alter ego breaking free.

The character has appeared in numerous Spider-Man animations and video games, and is portrayed by Dylan Baker (whose version never transformed into The Lizard) in the 2004 film Spider-Man 2 and its 2007 sequel Spider-Man 3, and by Rhys Ifans in the 2012 film The Amazing Spider-Man.

Monitor lizard

The monitor lizards are large lizards in the genus Varanus. They are native to Africa, Asia and Oceania, but are now found also in the Americas as an invasive species. A total of 79 species are currently recognized.

Monitor lizards have long necks, powerful tails and claws, and well-developed limbs. The adult length of extant species ranges from 20 cm (7.9 in) in some species, to over 3 m (10 ft) in the case of the Komodo dragon, though the extinct varanid known as megalania (Varanus priscus) may have been capable of reaching lengths of more than 7 m (23 ft). Most monitor species are terrestrial, but arboreal and semiaquatic monitors are also known. While most monitor lizards are carnivorous, eating eggs, smaller reptiles, fish, birds and small mammals, some also eat fruit and vegetation, depending on where they live.

Reptilian humanoid

Reptilian humanoids or simply, reptilians (also called reptoids, lizard people, reptiloids, saurians, Draconians) are purported humanoids with the characteristics of reptiles that play a prominent role in fantasy, science fiction, ufology, and conspiracy theories. The idea of reptilians was popularised by David Icke, a conspiracy theorist who claims shape-shifting reptilian aliens control Earth by taking on human form and gaining political power to manipulate human societies. Icke has stated on multiple occasions that many world leaders are, or are possessed by, so-called reptilians.


Rock–paper–scissors (also known as scissors–rock–paper or other variants) is a hand game usually played between two people, in which each player simultaneously forms one of three shapes with an outstretched hand. These shapes are "rock" (a closed fist), "paper" (a flat hand), and "scissors" (a fist with the index finger and middle finger extended, forming a V). "Scissors" is identical to the two-fingered V sign (also indicating "victory" or "peace") except that it is pointed horizontally instead of being held upright in the air.

A simultaneous, zero-sum game, it has only two possible outcomes: a draw, or a win for one player and a loss for the other.

A player who decides to play rock will beat another player who has chosen scissors ("rock crushes scissors" or sometimes "blunts scissors"), but will lose to one who has played paper ("paper covers rock"); a play of paper will lose to a play of scissors ("scissors cuts paper"). If both players choose the same shape, the game is tied and is usually immediately replayed to break the tie. The type of game originated in China and spread with increased contact with East Asia, while developing different variants in signs over time. Other names for the game in the English-speaking world include roshambo and other orderings of the three items, with "rock" sometimes being called "stone".Rock–paper–scissors is often used as a fair choosing method between two people, similar to coin flipping, drawing straws, or throwing dice in order to settle a dispute or make an unbiased group decision. Unlike truly random selection methods, however, rock–paper–scissors can be played with a degree of skill by recognizing and exploiting non-random behavior in opponents.


Saurischia ( saw-RIS-kee-ə, meaning "reptile-hipped" from the Greek sauros (σαῦρος) meaning 'lizard' and ischion (ἴσχιον) meaning 'hip joint') is one of the two basic divisions of dinosaurs (the other being Ornithischia). ‘Saurischia’ translates to lizard-hipped.

In 1888, Harry Seeley classified dinosaurs into two orders, based on their hip structure, though today most paleontologists classify Saurischia as an unranked clade rather than an order.


Skinks are lizards belonging to the family Scincidae and the infraorder Scincomorpha. With more than 1,500 described species, the Scincidae are one of the most diverse families of lizards.

The Lizard

For the village also called The Lizard, see Lizard (village)

The Lizard (Cornish: An Lysardh) is a peninsula in southern Cornwall, England, United Kingdom. The most southerly point of the British mainland is near Lizard Point at grid reference SW 701115. Lizard village, also known as The Lizard, is the most southerly on the British mainland, and is in the civil parish of Landewednack, the most southerly parish. The valleys of the River Helford and Loe Pool form the northern boundary, with the rest of the peninsula surrounded by sea. The area measures about 14 by 14 miles (23 km × 23 km). The Lizard is one of England's natural regions and has been designated as national character area 157 by Natural England. The peninsula is known for its geology and for its rare plants and lies within the Cornwall Area of Outstanding Natural Beauty (AONB). Almost a third of Cornwall has AONB designation, with the same status and protection as a National Park.

The name "Lizard" is most probably a corruption of the Cornish name "Lys Ardh", meaning "high court"; it is purely coincidental that much of the peninsula is composed of serpentinite-bearing rock. The Lizard peninsula's original name may have been the Celtic name "Predannack" ("British one"); during the Iron Age (Pytheas c. 325 BC) and Roman period, Britain was known as Pretannike (in Greek) and as Albion (and Britons the "Pretani").

The Lizard's coast is particularly hazardous to shipping and the seaways round the peninsula were historically known as the "Graveyard of Ships" (see below). The Lizard Lighthouse was built at Lizard Point in 1752 and the RNLI operates The Lizard lifeboat station.

This page is based on a Wikipedia article written by authors (here).
Text is available under the CC BY-SA 3.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.