Lizard Fossil range: Jurassic - Recent
Central bearded dragon, Pogona vitticeps
Scientific classification
Kingdom: Animalia Phylum: Chordata Superclass: Tetrapoda Class: Sauropsida Order: Squamata Suborder: Lacertilia* Günther, 1867
Families
Many, see text. The Jurassic is a geologic period and system that extends from about Ma (million years ago to  Ma that is from the end of the Triassic to the beginning Central (or Inland) Bearded Dragon are common names for the species Pogona vitticeps, a type of agamid Lizard occurring Chordates ( Phylum Chordata) are a group of Animals that includes the Vertebrates together with several closely related Invertebrates Tetrapods ( Greek τετραποδη tetrapoda, Latin Quadruped, "four-footed" are Vertebrate Animals Reptiles, or members of the class Reptilia are air-breathing Cold-blooded Vertebrates that have skin covered in scales as opposed to hair or feathers Squamata (scaled reptiles is the largest recent order of Reptiles including Lizards and Snakes Members of the order are distinguished by In Phylogenetics, a group of organisms is said to be paraphyletic if the group contains its most recent common ancestor but does not contain all Albrecht Karl Ludwig Gotthilf Günther FRS (also Albert Charles Lewis Gotthilf Gunther) October 3, 1830 – February 1 In Biological classification, family ( Latin Lizards are a large and widespread group of Reptiles of the order Squamata, with nearly 5000 species and ranging across all continents except

Lizards are a large and widespread group of reptiles of the order Squamata, with nearly 5,000 species and ranging across all continents except Antarctica. Reptiles, or members of the class Reptilia are air-breathing Cold-blooded Vertebrates that have skin covered in scales as opposed to hair or feathers Squamata (scaled reptiles is the largest recent order of Reptiles including Lizards and Snakes Members of the order are distinguished by Most lizards have four limbs, external ears, a long tail, and are insectivores. Many can shed their tails in order to escape from predators, though this trait is not universal. Vision, including color vision, is particularly well developed in lizards, and most communicate with body language or bright colors on their bodies as well as via pheromones. The adult length of species within the order range from a few centimeters (some Caribbean geckos) to nearly three meters (Komodo Dragons), though most species are less than a 0. For the 2008 British film by Noel Clarke see Adulthood (film. In Biology, a species is one of the basic units of Biological classification and a Taxonomic rank. This article is about the taxonomic rank for the sequence of species in a taxonomic list see Taxonomic order In scientific classification used A centimetre ( American spelling: centimeter, symbol cm) is a unit of Length in the Metric system, equal to one hundredth For the region see Caribbean. The Caribbean Sea (kəˈrɪbiən or /ˌkærɨˈbiːən/ is a tropical Sea in the Western Hemisphere Geckos are small to average sized Lizards belonging to the family Gekkonidae which are found in warm climates throughout the world The metre or meter is a unit of Length. It is the basic unit of Length in the Metric system and in the International The Komodo dragon ( Varanus komodoensis) is a species of Lizard that inhabits the islands of Komodo, Rinca, Flores, Gili 5 lbs (220 grams).

Description

Any generic description of lizards is often complicated by the fact that many typical lizard traits are either retentions from their evolutionary ancestors (such as the basic, 4-limbed, tetrapod body form) or are either lost or changed in some species (loss of limbs, loss of external ears, loss of the tail, etc. Tetrapods ( Greek τετραποδη tetrapoda, Latin Quadruped, "four-footed" are Vertebrate Animals )

Common chamaeleon Chamaeleo chamaeleon

Lizards are reptiles, and universally possess scaly skin and a skull with many fused or reduced bones. The Common Chameleon is the only species of Chamaleonidae of Europe. Reptiles, or members of the class Reptilia are air-breathing Cold-blooded Vertebrates that have skin covered in scales as opposed to hair or feathers In most biological nomenclature a scale ( Greek lepid, Latin squama) is a small rigid plate that grows out of an Animal Most lizards retain the typical tetrapod body plan of a short neck, four limbs of roughly equal size ending in five toes each, a moderately long body, and a long tail. Tetrapods ( Greek τετραποδη tetrapoda, Latin Quadruped, "four-footed" are Vertebrate Animals Most lizards possess external ears and have movable eyelids. Encompassing forty families, there is tremendous variety in colour, appearance and size. In Biological classification, family ( Latin Most lizards are oviparous, though a few species are viviparous. Oviparous animals are animals that lay eggs, with little or no other Embryonic development within the mother A viviparous Animal is an animal employing vivipary: the embryo develops inside the body of the mother as opposed to outside in an egg ( Ovipary Many are also capable of regeneration of lost limbs or tails. In Biology, an Organism is said to regenerate a lost or damaged part if the part regrows so that the original function is restored Almost all lizards are carnivorous, though most are so small that insects are their primary prey, however a few species are omnivorous or herbivorous, and others have reached sizes where they can prey on other vertebrates. Many lizards are good climbers or fast sprinters. Some can run bipedally, such as the collared lizard and some can even run across the surface of water to escape, namely the basilisk. The Oklahoma Collared Lizard or Collared Lizard, Crotaphytus collaris, is a North American lizard that can reach a foot (30 cm long in length (including In European bestiaries and Legends a basilisk ('bæzɪlɪsk from the Greek βασιλίσκος basilískos, "little king" Many lizards can change colour in response to their environments or in times of stress. The most familiar example is the chameleon, but more subtle colour changes occur in other lizard species as well such as the anole, also known as the "American chameleon," "house chameleon" or "chamele". Chameleons (family Chamaeleonidae) are squamates that belong to one of the best-known Lizard families

Some lizard species, including the glass lizard and flap-footed lizards, have lost their legs or reduced them to the point they are non-functional. The glass lizards or glass snakes, Genus Ophisaurus, are a group of reptiles that resemble Snakes but are actually Lizards The Pygopodidae, or flap-foots', are a family of legless lizards related to the Geckos They have unusually long slender bodies giving them a strong resemblance However, some vestigial structures remain. Vestigiality describes homologous characters of Organisms which have lost all or most of their original function in a species through Snakes, which evolved from the ancestors of monitor lizards, are characterized by lack of eyelids, lack of an external ear, a forked tongue, and having a highly elongate body (as opposed to a normal body but extremely long tail). Monitor lizards are the family Varanidae, a group of carnivorous lizards which includes the largest living lizard the Komodo dragon. While any given legless lizard species (of which there are many) may match on one or two of these characteristics, they invariably differ from snakes in others. For example, flap-footed lizards lack eyelids as do true snakes, but can be distinguished by their external ears. The Pygopodidae, or flap-foots', are a family of legless lizards related to the Geckos They have unusually long slender bodies giving them a strong resemblance

Lizards are part of the reptile family meaning that they have no inner means of achieving homeostatis. As a result they must keep careful watch of their body temperature. This need requires lizards to live in areas with consistently high temperatures. Lizards are rarely seen in the upper half of the United States and most European countries.

Senses and communication

Lizards employ many diverse methods of communication. Like many other animals, they have an acute sense of smell, detecting scents of their prey or pheromones from other lizards. The primary organ of scent in lizards is a vomeronasal organ in the roof of the mouth, and lizards gather scents by flicking out their tongues, then retracting them and delivering the captured odor molecules to this organ. Some large carnivorous lizards, such as tegus and monitor lizards, have forked tongues like snakes, to take advantage of this organ better. As a result, many male lizards possess enlarged pores on the underside of their thighs, which they rub against objects to mark their territory.

While most lizards can hear well, few are capable of vocalizations or otherwise making noise. The exception to this rule is the geckos, which communicate through a wide variety of barks, chirps and whistles, with each species having specific patterns and sounds.

Frill-necked lizard Chlamydosaurus kingii

Sight is quite important for most lizards, both for locating prey and for communication, and as such, many lizards have highly acute color vision. The Frill-necked Lizard, or Frilled Lizard also known as the Frilled Dragon, ( Chlamydosaurus kingii) is so called because of the large ruff of skin which Most lizards rely heavily on body language, using specific postures, gestures and movements to define territory, resolve disputes, and entice mates. Some species of lizard also utilize bright colors, such as the iridescent patches on the belly of Sceloporus. These colors would be highly visible to predators, so are often hidden on the underside or between scales and only revealed when necessary.

A particular innovation in this respect is the dewlap, a brightly colored patch of skin on the throat, usually hidden between scales. When a display is needed, the lizards erect the hyoid bone of their throat, resulting in a large vertical flap of brightly colored skin beneath the head which can be then used for communication. Anoles are particularly famous for this display, with each species having specific colors, including patterns only visible under ultraviolet light, as lizards can often see UV.

Evolution and relationships

The retention of the basic tetrapod body form by lizards makes it tempting to assume any similar animal, alive or extinct, is also a lizard. However, this is not the case, and lizards are part of a well-defined group.

The first reptile was superficially lizard-like, but had a solid, box-like skull, with openings only for eyes, nostrils, etc (termed Anapsid). These organisms later gave rise to two new groups with additional holes in the skull to make room for and anchor larger jaw muscles. Those with a single hole, the Synapsids, became modern mammals. The Diapsids, possessing two holes, continued to diversify. The Archosaurs retained the basic Diapsid skull, and gave rise to a bewildering array of animals, most famous being the dinosaurs and their descendants, birds. The Lepidosaurs began to reduce the skull bones, making the skull lighter and more flexible. Modern tuataras retain the basic Lepidosaur skull, distinguishing them from true lizards in spite of superficial similarities. Squamates, including snakes and all true lizards, further lightened the skull by eliminating the lower margin of the lower skull opening.

Green iguanas (Iguana iguana), are popular exotic pets. The green iguana or common iguana ( Iguana iguana) is a large Arboreal Herbivorous Species of Lizard of the Genus

Relationship to humans

Most lizard species are harmless to humans. Only the very largest lizard species pose threat of death; the Komodo dragon, for example, has been known to stalk, attack, and kill humans. The Komodo dragon ( Varanus komodoensis) is a species of Lizard that inhabits the islands of Komodo, Rinca, Flores, Gili The venom of the Gila monster and beaded lizard is not usually deadly but they can inflict extremely painful bites due to powerful jaws. The Gila monster (ˈhiːlə HEE-la Heloderma suspectum, is a species of venomous Lizard native to the Southwestern United States and northern The chief impact of lizards on humans is positive as they are significant predators of pest species; numerous species are prominent in the pet trade; some are eaten as food (for example, Green Iguanas in Central America); and lizard symbology plays important, though rarely predominant roles in some cultures (e. A pest is an organism which has characteristics that are regarded by Humans as injurious or unwanted A pet is an Animal kept for companionship and enjoyment or a househeld animal as opposed to Livestock, Laboratory animals Working animals Food is any substance usually composed primarily of Carbohydrates Fats water and/or Proteins that can be eaten or drunk by an The green iguana or common iguana ( Iguana iguana) is a large Arboreal Herbivorous Species of Lizard of the Genus Culture (from the Latin cultura stemming from colere, meaning "to cultivate" generally refers to patterns of human activity and the symbolic g. Tarrotarro in Australian mythology). The Moche people of ancient Peru worshipped animals and often depicted lizards in their art. The Moche civilization (alternately the Mochica culture Early Chimu Pre-Chimu Proto-Chimu etc Peru (Perú Piruw Piruw officially the Republic of Peru ( reˈpuβlika del peˈɾu is a country in western South America. ^[1] The Indian Monitor lizard (GOH) was used by tribals to climb clifs. some lizards have very spikey and thin layers of skin.

Classification

Plumed Basilisk, Basiliscus plumifrons

Zebra-tailed Lizard, Callisaurus draconoides

Red-headed rock agama, Agama agama

Gila monster, Heloderma s. The plumed basilisk ( Basiliscus plumifrons) also called a green basilisk, is a Species of Lizard native to Latin America. Zebra-tailed lizards live in open desert with fairly hard-packed soil scattered vegetation and scattered rocks typically desert flats washes and plains Agama agama is a species of Lizard from the Agamidae family, found in most of Sub-saharan Africa. The Gila monster (ˈhiːlə HEE-la Heloderma suspectum, is a species of venomous Lizard native to the Southwestern United States and northern suspectum

Green tree monitor lizard, Varanus prasinus

Collared Lizard (Crotaphytus collaris, on left) and Common Chuckwallah (Sauromalus ater, on right). Monitor lizards are the family Varanidae, a group of carnivorous lizards which includes the largest living lizard the Komodo dragon.

Suborder Lacertilia (Sauria) - (Lizards)

• Family Bavarisauridae
• Family Eichstaettisauridae
• Infraorder Iguania
  • Family Arretosauridae
  • Family Euposauridae
  • Family Corytophanidae (casquehead lizards)
  • Family Iguanidae (iguanas and spinytail iguanas)
  • Family Phrynosomatidae (earless, spiny, tree, side-blotched and horned lizards)
  • Family Polychrotidae (anoles)
    • Family Leiosauridae (see Polychrotinae)
  • Family Tropiduridae (neotropical ground lizards)
    • Family Liolaemidae (see Tropidurinae)
    • Family Leiocephalidae (see Tropidurinae)
  • Family Crotaphytidae (collared and leopard lizards)
  • Family Opluridae (Madagascar iguanids)
  • Family Hoplocercidae (wood lizards, clubtails)
  • Family Priscagamidae
  • Family Isodontosauridae
  • Family Agamidae (agamas)
  • Family Chamaeleonidae (chameleons)
• Infraorder Gekkota
  • Family Gekkonidae (geckos)
  • Family Pygopodidae (legless lizards)
  • Family Dibamidae (blind lizards)
• Infraorder Scincomorpha
  • Family Paramacellodidae
  • Family Slavoiidae
  • Family Scincidae (skinks)
  • Family Cordylidae (spinytail lizards)
  • Family Gerrhosauridae (plated lizards)
  • Family Xantusiidae (night lizards)
  • Family Lacertidae (wall lizards or true lizards)
  • Family Mongolochamopidae
  • Family Adamisauridae
  • Family Teiidae (tegus and whiptails)
  • Family Gymnophthalmidae (spectacled lizards)
• Infraorder Diploglossa
  • Family Anguidae (glass lizards)
  • Family Anniellidae (American legless lizards)
  • Family Xenosauridae (knob-scaled lizards)
• Infraorder Platynota (Varanoidea)
  • Family Varanidae (monitor lizards)
  • Family Lanthanotidae (earless monitor lizards)
  • Family Helodermatidae (gila monsters & beaded lizards)
  • Family Mosasauridae (marine lizards)

References

General references

• Byiiuo, John L. (1979). The Audubon Society Field Guide to Reptiles and Amphibians of North America. Alfred A. Knopf, 581. ISBN 0394508246.  
• Capula, Massimo; Behler (1989). Simon & Schuster's Guide to Reptiles and Amphibians of the World. New York: Simon & Schuster. New York ( is a state in the Mid-Atlantic and Northeastern regions of the United States and is the nation's third most populous Simon & Schuster Inc, a division of CBS Corporation, is a Publisher founded in New York in 1924 by Richard L ISBN 0671690981.  
• Cogger, Harold (1992). Harold (Hal Cogger is an Australian Herpetologist. He was curator of Reptiles and Amphibians at the Australian Museum from 1960-1975 and Deputy Reptiles & Amphibians. Sydney, Australia: Weldon Owen. Sydney (ˈsɪdniː is the most populous city in Australia, with a Metropolitan area population of approximately 4 ISBN 0831727861.  
• Conant, Roger (1991). Roger Conant ( May 6, 1909 &ndash December 19, 2003) was an American herpetologist, author educator and conservationist A Field Guide to Reptiles and Amphibians Eastern/Central North America. Boston, Massachusetts: Houghton Mifflin Company. The Commonwealth of Massachusetts ( is a state located in the New England region of the northeastern United States. ISBN 0395583896.  
• Ditmars, Raymond L (1933). Raymond Lee Ditmars (born June 22, 1876 from Newark, New Jersey, died May 12, 1942 in New York City) was an Reptiles of the World: The Crocodilians, Lizards, Snakes, Turtles and Tortoises of the Eastern and Western Hemispheres. New York: Macmillian, 321. New York ( is a state in the Mid-Atlantic and Northeastern regions of the United States and is the nation's third most populous  
• Freiberg, Dr. Marcos (1984). The World of Venomous Animals. New Jersey: TFH Publications. New Jersey ( is a state in the Mid-Atlantic and Northeastern regions of the United States. ISBN 0876665679.  
• Gibbons, J. Whitfield (1983). Their Blood Runs Cold: Adventures With Reptiles and Amphibians. Alabama: University of Alabama Press, 164. Alabama (formally the State of Alabama;) is a State located in the southern region of the United States of America. ISBN 978-0817301354.  
• Rosenfeld, Arthur (1989). Exotic Pets. New York: Simon & Schuster, 293. New York ( is a state in the Mid-Atlantic and Northeastern regions of the United States and is the nation's third most populous Simon & Schuster Inc, a division of CBS Corporation, is a Publisher founded in New York in 1924 by Richard L ISBN 067147654.