Chameleon
Overview
Chameleons are a distinctive and highly specialized clade
Clade
A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...

 of lizard
Lizard
Lizards are a widespread group of squamate reptiles, with nearly 3800 species, ranging across all continents except Antarctica as well as most oceanic island chains...

s. They are distinguished by their parrot-like zygodactylous feet, their separately mobile and stereoscopic eyes, their very long, highly modified, and rapidly extrudable tongues, their swaying gait, the possession by many of a prehensile tail, crests or horns on their distinctively shaped heads, and the ability of some to change color.
Discussions
Encyclopedia
Chameleons are a distinctive and highly specialized clade
Clade
A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...

 of lizard
Lizard
Lizards are a widespread group of squamate reptiles, with nearly 3800 species, ranging across all continents except Antarctica as well as most oceanic island chains...

s. They are distinguished by their parrot-like zygodactylous feet, their separately mobile and stereoscopic eyes, their very long, highly modified, and rapidly extrudable tongues, their swaying gait, the possession by many of a prehensile tail, crests or horns on their distinctively shaped heads, and the ability of some to change color. Uniquely adapted for climbing and visual hunting, the approximately 160 species of chameleon range from Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...

, Madagascar
Madagascar
The Republic of Madagascar is an island country located in the Indian Ocean off the southeastern coast of Africa...

, Spain
Spain
Spain , officially the Kingdom of Spain languages]] under the European Charter for Regional or Minority Languages. In each of these, Spain's official name is as follows:;;;;;;), is a country and member state of the European Union located in southwestern Europe on the Iberian Peninsula...

 and Portugal
Portugal
Portugal , officially the Portuguese Republic is a country situated in southwestern Europe on the Iberian Peninsula. Portugal is the westernmost country of Europe, and is bordered by the Atlantic Ocean to the West and South and by Spain to the North and East. The Atlantic archipelagos of the...

, across south Asia
Asia
Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...

, to Sri Lanka
Sri Lanka
Sri Lanka, officially the Democratic Socialist Republic of Sri Lanka is a country off the southern coast of the Indian subcontinent. Known until 1972 as Ceylon , Sri Lanka is an island surrounded by the Indian Ocean, the Gulf of Mannar and the Palk Strait, and lies in the vicinity of India and the...

, have been introduced
Introduced species
An introduced species — or neozoon, alien, exotic, non-indigenous, or non-native species, or simply an introduction, is a species living outside its indigenous or native distributional range, and has arrived in an ecosystem or plant community by human activity, either deliberate or accidental...

 to Hawaii
Hawaii
Hawaii is the newest of the 50 U.S. states , and is the only U.S. state made up entirely of islands. It is the northernmost island group in Polynesia, occupying most of an archipelago in the central Pacific Ocean, southwest of the continental United States, southeast of Japan, and northeast of...

, California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...

 and Florida
Florida
Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...

, and are found in warm habitats that vary from rain forest to desert
Desert
A desert is a landscape or region that receives an extremely low amount of precipitation, less than enough to support growth of most plants. Most deserts have an average annual precipitation of less than...

 conditions.

Etymology

The English word chameleon (also chamaeleon) derives from Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...

 chamaeleō, a borrowing of the Ancient Greek
Ancient Greek
Ancient Greek is the stage of the Greek language in the periods spanning the times c. 9th–6th centuries BC, , c. 5th–4th centuries BC , and the c. 3rd century BC – 6th century AD of ancient Greece and the ancient world; being predated in the 2nd millennium BC by Mycenaean Greek...

 χαμαιλέων (khamailéōn), a compound
Compound (linguistics)
In linguistics, a compound is a lexeme that consists of more than one stem. Compounding or composition is the word formation that creates compound lexemes...

 of χαμαί (khamaí) "on the ground" and λέων (léōn) "lion". The Greek word is a calque
Calque
In linguistics, a calque or loan translation is a word or phrase borrowed from another language by literal, word-for-word or root-for-root translation.-Calque:...

 translating the Akkadian
Akkadian language
Akkadian is an extinct Semitic language that was spoken in ancient Mesopotamia. The earliest attested Semitic language, it used the cuneiform writing system derived ultimately from ancient Sumerian, an unrelated language isolate...

 nēš qaqqari, "ground lion".

Evolution

The oldest known chameleon fossil is that of Chamaeleo caroliquarti
Chamaeleo caroliquarti
Chamaeleo caroliquarti is an extinct species of chameleon from the Lower Miocene found in Central Europe. With fossil evidence at about 26 million years old, it is the oldest known chameleon....

, found in Europe and dated to about 26 mya. However the chameleons are probably far older than that, perhaps sharing a common ancestor with iguanids
Iguanidae
Iguanidae is a family of lizards, composed of iguanas and related species.-Classification of Iguanidae:Two different classification schemes have been used to define the structure of this family. These are the "traditional" classification and the classification presented by Frost et al. .Frost et...

 and agamids more than 100 mya (agamids being more closely related). Fossil evidence has also been found in Africa and Asia, and suggests that chameleons were once more widespread than they are today. They may have their origins in Madagascar, which today is home to nearly half of all the 150 or more known species in this family, and later dispersed to other areas. Monophyly
Monophyly
In common cladistic usage, a monophyletic group is a taxon which forms a clade, meaning that it contains all the descendants of the possibly hypothetical closest common ancestor of the members of the group. The term is synonymous with the uncommon term holophyly...

 of the family is supported by several studies.

Description

Chameleons vary greatly in size and body structure, with maximum total length varying from 3.3 cm (1.3 in.) in Brookesia minima
Brookesia minima
Brookesia minima, , is a diminutive chameleon "often said to be the smallest" or "probably the smallest" of the Chamaeleonidae.-Range:B...

(one of the world's smallest reptiles) to 68.5 cm (27 in.) in the male Furcifer oustaleti
Malagasy Giant Chameleon
The Oustalet's or Malagasy Giant Chameleon is a very large species of chameleon that is endemic to Madagascar, but also has been introduced near Nairobi in Kenya . It occurs in a wide range of habitats, even among degraded vegetation within villages, but is relatively rare in primary forest...

. Many have head or facial ornamentation, such as nasal protrusions, or horn-like projections in the case of Trioceros jacksonii, or large crests on top of their head, like Chamaeleo calyptratus
Veiled Chameleon
The veiled chameleon, Chamaeleo calyptratus, is a large species of chameleon found in the mountain regions of Yemen, United Arab Emirates and Saudi Arabia. It is also sometimes referred to as the Yemen Chameleon....

. Many species are sexually dimorphic
Sexual dimorphism
Sexual dimorphism is a phenotypic difference between males and females of the same species. Examples of such differences include differences in morphology, ornamentation, and behavior.-Examples:-Ornamentation / coloration:...

, and males are typically much more ornamented than the female chameleons. Chameleons are often sold at pet stores and are not rare to have as household pets. Below is a table of common pet chameleons:
Species' Scientific Name Species' Common Name Typical Total Length (Male) Typical Total Length (Female) Color Typical Lifespan (Years)
Chamaeleo calyptratus Veiled Chameleon
Veiled Chameleon
The veiled chameleon, Chamaeleo calyptratus, is a large species of chameleon found in the mountain regions of Yemen, United Arab Emirates and Saudi Arabia. It is also sometimes referred to as the Yemen Chameleon....

 
14"-24" 10-13" Green & Light Colors ≈5
Trioceros jacksonii  Jackson's Chameleon  9"-13" 10"-13" Green & Light Colors ≈5-10
Furcifer pardalis Panther Chameleon
Panther chameleon
The Panther Chameleon is a species of chameleon. It lives in the eastern and northern parts of Madagascar in a tropical forest biome. Additionally, it has been introduced to Réunion and Mauritius.- Taxonomy :...

 
15"-21" 9"-13" Darker Colors ≈5 (2-3 for birthing females)
Rieppeleon brevicaudatus
Rieppeleon brevicaudatus
Rieppeleon brevicaudatus, commonly known as the bearded leaf chameleon or bearded pygmy chameleon, is a chameleon originating from the eastern Usambara and Uluguru mountains in northeastern Tanzania. It is easily distinguished from others in the Rieppeleon genus by the presence of a "beard" below...

Bearded Pygmy Chameleon  2"-3" 2"-3" Brown, Beige, Green ≈3-5
Rhampholeon spectrum
Rhampholeon spectrum
The Spectral Pygmy Chameleon is one of the so-called "dwarf chameleons", aka "leaf chameleons", from mainland Africa....

Spectral Pygmy Chameleon  3"-4" 2"-4" Tan & Gray Unknown
Rhampholeon temporalis Pygmy Chameleon  2.5"-4" 2"-3.5" Gray & Brown Unknown


Chameleon species have in common their foot structure, eyes, tongues and a lack of ears.
Chameleons are didactyl
Dactyl
Dactyl may refer to:* Dactyl , a creature in Greek mythology* Dactyl , a metrical foot consisting of one long syllable and two short* Dactyl , the small natural satellite orbiting the asteroid Ida...

: on each foot the five toes are fused into a group of two and a group of three, giving the foot a tongs
Tongs
Tongs are used for gripping and lifting tools, of which there are many forms adapted to their specific use. Some are merely large pincers or nippers, but the greatest number fall into three classes:...

-like appearance. These specialized feet allow chameleons to grip tightly to narrow branches. Each toe is equipped with a sharp claw to gain traction on surfaces such as bark when climbing. The claws make it easy to see how many toes are fused into each part of the foot — two toes on the outside of each front foot and three on the inside.

Their eyes are the most distinctive among the reptiles. The upper and lower eyelids are joined, with only a pinhole large enough for the pupil to see through. They can rotate and focus separately to observe two different objects simultaneously, this lets their eyes move independently from each other. It in effect gives them a full 360-degree arc of vision around their body. When prey is located, both eyes can be focused in the same direction, giving sharp stereoscopic vision and depth perception
Depth perception
Depth perception is the visual ability to perceive the world in three dimensions and the distance of an object. Depth sensation is the ability to move accurately, or to respond consistently, based on the distances of objects in an environment....

. They have very good eyesight for reptiles, letting them see small insects from a long (5–10 m) distance.

They lack a vomeronasal organ
Vomeronasal organ
The vomeronasal organ , or Jacobson's organ, is an auxiliary olfactory sense organ that is found in many animals. It was discovered by Frederik Ruysch and later by Ludwig Jacobson in 1813....

. Also, like snake
Snake
Snakes are elongate, legless, carnivorous reptiles of the suborder Serpentes that can be distinguished from legless lizards by their lack of eyelids and external ears. Like all squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales...

s, they do not have an outer or a middle ear
Ear
The ear is the organ that detects sound. It not only receives sound, but also aids in balance and body position. The ear is part of the auditory system....

. This suggests that chameleons might be deaf, although snakes can sense vibration using a bone called the quadrate
Quadrate bone
The quadrate bone is part of a skull in most tetrapods, including amphibians, sauropsids , and early synapsids. In these animals it connects to the quadratojugal and squamosal in the skull, and forms part of the jaw joint .- Evolutionary variation :In snakes, the quadrate bone has become elongated...

. Furthermore, some or maybe all chameleons, can communicate via vibrations that travel through solid substrates such as branches.

Chameleons have very long tongue
Tongue
The tongue is a muscular hydrostat on the floors of the mouths of most vertebrates which manipulates food for mastication. It is the primary organ of taste , as much of the upper surface of the tongue is covered in papillae and taste buds. It is sensitive and kept moist by saliva, and is richly...

s (sometimes longer than their own body length) which they are capable of rapidly extending
Projectile use by living systems
Although projectiles are commonly used in human conflict, projectile use by living systems other than humans is relatively rare.-Liquid projectiles:...

 out of the mouth.
The tongue extends out faster than human eyes can follow, at around 26 body lengths per second. The tongue hits the prey in about 30 thousandths of a second. The tongue of the chameleon is a complex arrangement of bone, muscle and sinew. At the base of the tongue there is a bone and this is shot forward giving the tongue the initial momentum it needs to reach the prey quickly. At the tip of the elastic tongue there is a muscular, club-like structure covered in thick mucus that forms a suction cup. Once the tip sticks to a prey item, it is drawn quickly back into the mouth, where the chameleon's strong jaws crush it and it is consumed. Ultraviolet light is part of the visible spectrum for chameleons. Chameleons exposed to ultraviolet light show increased social behavior and activity levels, are more inclined to bask and feed and are also more likely to reproduce as it has a positive effect on the pineal gland
Pineal gland
The pineal gland is a small endocrine gland in the vertebrate brain. It produces the serotonin derivative melatonin, a hormone that affects the modulation of wake/sleep patterns and seasonal functions...

.

Distribution and habitat

Chameleons are primarily found in the mainland of sub-Saharan Africa
Sub-Saharan Africa
Sub-Saharan Africa as a geographical term refers to the area of the African continent which lies south of the Sahara. A political definition of Sub-Saharan Africa, instead, covers all African countries which are fully or partially located south of the Sahara...

 and on the island of Madagascar, although a few species are also found in northern Africa, southern Europe
Southern Europe
The term Southern Europe, at its most general definition, is used to mean "all countries in the south of Europe". However, the concept, at different times, has had different meanings, providing additional political, linguistic and cultural context to the definition in addition to the typical...

, the Middle East
Middle East
The Middle East is a region that encompasses Western Asia and Northern Africa. It is often used as a synonym for Near East, in opposition to Far East...

, southern India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...

, Sri Lanka
Sri Lanka
Sri Lanka, officially the Democratic Socialist Republic of Sri Lanka is a country off the southern coast of the Indian subcontinent. Known until 1972 as Ceylon , Sri Lanka is an island surrounded by the Indian Ocean, the Gulf of Mannar and the Palk Strait, and lies in the vicinity of India and the...

 and several smaller islands in the western Indian Ocean. There are introduced, feral populations of veiled
Veiled Chameleon
The veiled chameleon, Chamaeleo calyptratus, is a large species of chameleon found in the mountain regions of Yemen, United Arab Emirates and Saudi Arabia. It is also sometimes referred to as the Yemen Chameleon....

 and Jackson's
Chamaeleo jacksonii
Trioceros jacksonii is an African chameleon belonging to the chameleon family .- Taxonomy :...

 chameleons in Hawaii
Hawaii
Hawaii is the newest of the 50 U.S. states , and is the only U.S. state made up entirely of islands. It is the northernmost island group in Polynesia, occupying most of an archipelago in the central Pacific Ocean, southwest of the continental United States, southeast of Japan, and northeast of...

 and isolated pockets of feral Jackson's chameleons have been reported in California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...

 and Florida
Florida
Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...

.

Chameleons inhabit all kinds of tropical
Tropics
The tropics is a region of the Earth surrounding the Equator. It is limited in latitude by the Tropic of Cancer in the northern hemisphere at approximately  N and the Tropic of Capricorn in the southern hemisphere at  S; these latitudes correspond to the axial tilt of the Earth...

 and mountain rain forests, savanna
Savanna
A savanna, or savannah, is a grassland ecosystem characterized by the trees being sufficiently small or widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach the ground to support an unbroken herbaceous layer consisting primarily of C4 grasses.Some...

s and sometimes desert
Desert
A desert is a landscape or region that receives an extremely low amount of precipitation, less than enough to support growth of most plants. Most deserts have an average annual precipitation of less than...

s and steppe
Steppe
In physical geography, steppe is an ecoregion, in the montane grasslands and shrublands and temperate grasslands, savannas, and shrublands biomes, characterized by grassland plains without trees apart from those near rivers and lakes...

s. The typical chameleons from the subfamily Chamaeleoninae are arboreal and usually found in trees or bushes, although a few (notably the Namaqua Chameleon
Namaqua Chameleon
The Namaqua Chameleon is a ground living lizard found in the Namib Desert of Namibia and southern Angola.-Survival Techniques:...

) are partially or largely terrestrial
Terrestrial animal
Terrestrial animals are animals that live predominantly or entirely on land , as compared with aquatic animals, which live predominantly or entirely in the water , or amphibians, which rely on a combination of aquatic and terrestrial habitats...

. Most species from the subfamily Brookesiinae, which includes the genera Brookesia
Brookesia
Brookesia is a genus of chameleons found in Madagascar, that range from small to very small in size, and are known collectively as Leaf Chameleons . It includes the species considered to be the world's smallest chameleons, and are also among the smallest reptiles...

, Rieppeleon
Rieppeleon
Rieppeleon is a genus of small, typically brown chameleons found in forests and savannas in central East Africa...

and Rhampholeon
Rhampholeon
Rhampholeon, commonly known as pygmy chameleons or African leaf chameleons, are a genus of small chameleons found in central East Africa . They are found in forests, woodlands, thickets and savanna, and most species are restricted to highlands...

, live low in vegetation or on the ground among leaf litter.

Reproduction

Chameleons are mostly oviparous, some being ovoviviparous.

The oviparous species lay eggs 3–6 weeks after copulation. The female will climb down to the ground and begin digging a hole, anywhere from 10–30 cm (4–12 in.) deep depending on the species. The female turns herself around at the bottom of the hole and deposits her eggs. Once finished, the female buries lina and leaves the nesting site. Clutch sizes vary greatly with species. Small Brookesia
Brookesia
Brookesia is a genus of chameleons found in Madagascar, that range from small to very small in size, and are known collectively as Leaf Chameleons . It includes the species considered to be the world's smallest chameleons, and are also among the smallest reptiles...

species may only lay 2–4 eggs, while large Veiled Chameleon
Veiled Chameleon
The veiled chameleon, Chamaeleo calyptratus, is a large species of chameleon found in the mountain regions of Yemen, United Arab Emirates and Saudi Arabia. It is also sometimes referred to as the Yemen Chameleon....

s (Chamaeleo calyptratus) have been known to lay clutches of 80–100 eggs. Clutch sizes can also vary greatly among the same species. Eggs generally hatch after 4–12 months, again depending on species. The eggs of Parson's Chameleon
Parson's chameleon
The Parson's chameleon is a very large species of chameleon that is endemic to isolated pockets of humid primary forest in eastern and northern Madagascar. It is listed on CITES Appendix II, meaning that trade in this species is regulated...

 (Calumma parsonii), a species which is rare in captivity, are believed to take upwards of 24 months to hatch.

The ovoviviparous species, such as the Jackson's Chameleon (Trioceros jacksonii) have a 5–6 month gestation period. The newborn are in a transparent membrane and they are still sleeping, once they touch the ground or branch, they will wake up and attempt to crawl out of the membrane. The female can have 8–31 live young at once.

Feeding behavior

Chameleons generally eat locust
Locust
Locusts are the swarming phase of short-horned grasshoppers of the family Acrididae. These are species that can breed rapidly under suitable conditions and subsequently become gregarious and migratory...

s, mantis, cricket
Cricket (insect)
Crickets, family Gryllidae , are insects somewhat related to grasshoppers, and more closely related to katydids or bush crickets . They have somewhat flattened bodies and long antennae. There are about 900 species of crickets...

s, grasshopper
Grasshopper
The grasshopper is an insect of the suborder Caelifera in the order Orthoptera. To distinguish it from bush crickets or katydids, it is sometimes referred to as the short-horned grasshopper...

 and other insect
Insect
Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...

s, but larger chameleons have been known to eat small bird
Bird
Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...

s and other lizards. A few species, such as Jackson's Chameleon (T. jacksonii) and the Veiled Chameleon
Veiled Chameleon
The veiled chameleon, Chamaeleo calyptratus, is a large species of chameleon found in the mountain regions of Yemen, United Arab Emirates and Saudi Arabia. It is also sometimes referred to as the Yemen Chameleon....

 (C. calyptratus) will consume small amounts of plant matter. Chameleons prefer running water to still water.

Chameleons require lots of vitamins and minerals. To ensure sufficient nutrients, zoo-keepers "gut-load" insects before feeding them to chameleons, by rearing them on a diet of potatoes, fish
Fish
Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups...

 flakes (tropical), dry puppy food, dark leafy greens, etc. and dusting them with vitamin and mineral powders.

Change of color

Some chameleon species are able to change their skin colors. Different chameleon species are able to change different colors which can include pink, blue, red, orange, green, black, brown, light blue, yellow, turquoise and purple.

The primary purpose of color change has been found to be due to social signalling, as opposed to camouflage, although both social signalling color change, and color change for purposes of camouflage do occur in most chameleons, to some extent. Color change is also used as an expression of the physiological condition of the lizard, and as a social indicator to other chameleons. Research suggests that social signaling was the primary driving force behind the evolution of color change, and that camouflage evolved as a secondary concern. Chameleons tend to show darker colors when angered, or attempting to scare or intimidate others, and males show lighter, multi-colored patterns when courting females.

Some varieties of chameleon—such as the Smith's dwarf chameleon
Smith's Dwarf Chamaeleon
Bradypodion taeniabronchum is known as Smith's Dwarf Chameleon or the Elandsberg Dwarf Chameleon. It is a species of lizard in the Chamaeleonidae family and is endemic to South Africa. It is critically endangered...

—use their color-changing ability to blend in with their surroundings, as an effective form of camouflage
Camouflage
Camouflage is a method of concealment that allows an otherwise visible animal, military vehicle, or other object to remain unnoticed, by blending with its environment. Examples include a leopard's spotted coat, the battledress of a modern soldier and a leaf-mimic butterfly...

.

The desert dwelling Namaqua Chameleon
Namaqua Chameleon
The Namaqua Chameleon is a ground living lizard found in the Namib Desert of Namibia and southern Angola.-Survival Techniques:...

 also uses color change as an aid to thermoregulation, becoming black in the cooler morning to absorb heat more efficiently, then a lighter grey colour to reflect light during the heat of the day - or showing both colours at the same time, neatly separated left from right by the spine.

Chameleons have specialized cells, collectively called chromatophores, that lie in layers under their transparent outer skin. The cells in the upper layer, called xanthophores and erythrophores, contain yellow and red pigment
Pigment
A pigment is a material that changes the color of reflected or transmitted light as the result of wavelength-selective absorption. This physical process differs from fluorescence, phosphorescence, and other forms of luminescence, in which a material emits light.Many materials selectively absorb...

s respectively. Below these is another layer of cells called iridophores or guanophores, and they contain the colorless crystalline substance guanine
Guanine
Guanine is one of the four main nucleobases found in the nucleic acids DNA and RNA, the others being adenine, cytosine, and thymine . In DNA, guanine is paired with cytosine. With the formula C5H5N5O, guanine is a derivative of purine, consisting of a fused pyrimidine-imidazole ring system with...

. These are particularly strong reflectors of the blue part of incident light
Light
Light or visible light is electromagnetic radiation that is visible to the human eye, and is responsible for the sense of sight. Visible light has wavelength in a range from about 380 nanometres to about 740 nm, with a frequency range of about 405 THz to 790 THz...

. If the upper layer of chromatophores appears mainly yellow, the reflected light becomes green
Green
Green is a color, the perception of which is evoked by light having a spectrum dominated by energy with a wavelength of roughly 520–570 nanometres. In the subtractive color system, it is not a primary color, but is created out of a mixture of yellow and blue, or yellow and cyan; it is considered...

 (blue
Blue
Blue is a colour, the perception of which is evoked by light having a spectrum dominated by energy with a wavelength of roughly 440–490 nm. It is considered one of the additive primary colours. On the HSV Colour Wheel, the complement of blue is yellow; that is, a colour corresponding to an equal...

 plus yellow
Yellow
Yellow is the color evoked by light that stimulates both the L and M cone cells of the retina about equally, with no significant stimulation of the S cone cells. Light with a wavelength of 570–590 nm is yellow, as is light with a suitable mixture of red and green...

). A layer of dark melanin
Melanin
Melanin is a pigment that is ubiquitous in nature, being found in most organisms . In animals melanin pigments are derivatives of the amino acid tyrosine. The most common form of biological melanin is eumelanin, a brown-black polymer of dihydroxyindole carboxylic acids, and their reduced forms...

 contained in melanophores is situated even deeper under the reflective iridophores. The melanophores determine the 'lightness' of the reflected light. These specialized cells are full of pigment granules, which are located in their cytoplasm. Dispersion of the pigment granules in the cell grants the intensity of appropriate color. If the pigment is equally distributed in the cell, the whole cell has the intensive color, which depends on the type of chromatophore cell. If the pigment is located only in the centre of the cell, the cell appears to be transparent. All these pigment cells can rapidly relocate their pigments, thereby influencing the color of the chameleon. Chameleons are born with cells call pigment
Pigment
A pigment is a material that changes the color of reflected or transmitted light as the result of wavelength-selective absorption. This physical process differs from fluorescence, phosphorescence, and other forms of luminescence, in which a material emits light.Many materials selectively absorb...

 this cells lie in layers under the chameleon's skin. The top layers of chromatophores have red or yellow pigment. The lower layers have blue or white pigment. When these pigment cells get bigger, the chameleon's skin color changes. Chromatophores change because the cells get a message from the brain to enlarge or to shrink. These actions cause cell pigments to mix, similar to paint, creating other colors like green or purple.

Classification

Family Chamaeleonidae
  • Subfamily Brookesiinae
    Brookesiinae
    Brookesiinae is a subfamily of chameleons and a member of the Family Chamaeleonidae.-Classification:There are three Genera in the Subfamily.Subfamily Chamaeleonidae*Genus Brookesia*Genus Rhampholeon*Genus Rieppeleon...

  • Subfamily Chamaeleoninae
    Chamaeleoninae
    Chamaeleoninae is the nominotypical subfamily of chameleons -Classification:There are eight currently recognised genera in the subfamily:*Genus Archaius*Genus Bradypodion*Genus Calumma*Genus Chamaeleo...


Parasites

A number of monoxenous coccidia
Coccidia
Coccidia is a subclass of microscopic, spore-forming, single-celled obligate parasites belonging to the apicomplexan class Conoidasida. Coccidian parasites infect the intestinal tracts of animals, and are the largest group of apicomplexan protozoa....

 are known to infect these species including species of the genera Choleoeimeria
Choleoeimeria
Choleoeimeria is a genus of protozoan parasites that infect the bilary tracts of reptiles. Morphologically they are similar to the Eimeria to who they are closely related...

, Eimeria
Eimeria
Eimeria is a genus of Apicomplexan parasites that includes various species responsible for the poultry disease coccidiosis. The genus is named for the German zoologist Theodor Eimer...

and Isospora
Isospora
Isospora is a genus of internal parasites classified under Coccidia.It is responsible for the condition isosporiasis.At least 248 species have been described in this genus, but most of them are little studied and it is doubtful whether all should be recognized as distinct species...

.

Recognised parasites include:
  • Choleoeimeria bohemii - Meller's chameleon (Trioceros melleri)
    Meller's Chameleon
    Trioceros melleri, with the common names Meller's Chameleon and Giant One-horned Chameleon is the largest species of chameleon from the African mainland . Meller's Chameleon gets its common name from a "Dr...

  • Choleoeimeria brookesiae - spiny leaf chameleon (Brookesia decaryi)
  • Choleoeimeria glawi - panther chameleon (Furcifer pardalis)
  • Choleoeimeria hirbayah - veiled chameleon (Chamaeleo calyptratus)
  • Choleoeimeria largeni - graceful chameleon (Chamaeleo gracilis)
  • Choleoeimeria tilburyi - Jackson's chameleon (Trioceros jacksonii)

  • Eimeria hajeki - pygmy chameleon (Rampholeon temporalis)
  • Eimeria vencesi - panther chameleon (Furcifer pardalis)
  • Eimeria worthi - Oustalet's chameleon (Furcifer oustaleti)

  • Isospora brygooi - panther chameleon (Furcifer pardalis)
  • Isospora jaracimrmani - veiled chameleon (Chamaeleo calyptratus)
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