Mediterranean chameleons (Chamaeleo chamaeleon), also called common chameleons, are native to coastal regions of northern Africa and the Levant, which includes Cyprus, Hatay, Israel, Jordan, Lebanon, Palestine, and Syria. In northern Africa, their geographic range extends from western Morocco to northern Egypt. Mediterranean chameleons also have populations from southwest Turkey southward to northwest Yemen. They have also been introduced to southern Portugal and Spain. Historically, there was a population on the island of Crete in Greece, although there have been no recent sightings. (Bartlett and Bartlett, 1995; Vogrin, et al., 2012; Yaacov, et al., 2012)
Mediterranean chameleons live in savannas, riparian habitats, forests and grasslands. Habitat elevation ranges from 0 to 800 m above sea level. They are arboreal, and commonly perch in branches of trees or shrubs, such as carob tree (Ceratonia siliqua), mastic tree (Pistacia lentiscus), and Palestine oak (Quercus calliprinos). Mediterranean chameleons typically select trees that are proportional to their size; since younger individuals are smaller, they select trees with thinner branches that they can more easily grip.
Mediterranean chameleons change their location depending on the time of day and on weather conditions, such as temperature and precipitation, in order to thermoregulate. To stay cool during the daytime, they perch in higher branches with more exposure to wind. At night, they move to areas with denser vegetation which protects them from wind and better conceals them from predators. Juveniles generally sleep on the ground in tall grass. (Hodar, et al., 2000; Keren-Rotem, et al., 2006; Tolley and Herrel, 2014)
Mediterranean chameleons differ in coloration, with some individuals being yellowish-brown and others being yellowish-green, dark green, or dark brown. Mediterranean chameleons can also actively change the color of their skin to lighter or darker shades of their typical coloration. It is a misconception that chameleons change color depending on the color of their background. Rather, their colors become more or less intense and may change in hue depending on weather, environmental stressors, and mood.
Mediterranean chameleons have flattened bodies with both dorsal and ventral crests on the posterior portion of their heads. Their bodies are covered in non-overlapping scales made from keratin. They have feet with digits that oppose each other, similar to zygodactyly. However, as opposed to true zygodactyly, in which the same number of digits are present on either side of each foot, chameleons have three digits on one side and two digits on the other side of their feet. Regardless, the opposition of these digits allows them to grip branches tightly. Mediterranean chameleons also have prehensile tails that assist them in gripping branches. Mediterranean chameleons have large eyes that are capable of moving independently from one another. They also have unique tongues, which can be as long as their bodies and are accompanied by highly specialized skeletal structures that allow them to launch their tongues at prey. Furthermore, their tongues have epithelial glands and papillae that produce sticky saliva and increase surface area, respectively, which makes catching prey easier.
Adult female Mediterranean chameleons weigh between 21 and 56 g, while adult males weigh between 17 and 37 g. Adult chameleons range from 7.7 to 16 cm in length. Juveniles weigh between 0.6 and 1.9 g and range from 3.3 to 4.1 cm in length. Juvenile color patterns and physical characteristics are the same as adults.
Mediterranean chameleons have noses that are rounded at the end, which distinguishes them from sympatric chameleon species. (Bartlett and Bartlett, 1995; Cuadrado, 2001a; Herrel, et al., 2000; Keren-Rotem, et al., 2006; Tolley and Herrel, 2014)
Mediterranean chameleons typically mate in September and females lay their eggs in underground burrows about 1 month later. However, immediately after females lay their eggs, embryos enter a stage of arrested development that lasts throughout winter. Eggs do not develop beyond the gastrula stage, regardless of the nest temperature, until temperatures begin to warm in spring. Development proceeds at a normal rate by April and hatching occurs in August. Total incubation time lasts around 10 months.
Once eggs hatch, hatchlings dig out of the burrows dug by their mothers. There is no parental investment after oviposition and juvenile spend the majority of their time foraging, protecting themselves from predators, and maintaining adequate body temperatures. Mediterranean chameleons exhibit indeterminate growth. (Andrews, et al., 2008)
Mediterranean chameleons generally form a mating pair that lasts for at least two days during the breeding season. Occasionally, males mate with more than one female during mating season, but only one at a time, making Mediterranean chameleons sequentially polygynous.
Males compete to mate preferentially with larger females. Larger, older females attract more mates, are courted earlier and are guarded for longer compared to smaller, younger females. It is likely that female body size is positively correlated with both reproductive success and offspring survival rates. Females that mate earlier in the breeding season have clutches of eggs with higher rates of offspring survival. Additionally, females that lay their eggs earlier have longer to forage for food and regain energy stores for winter.
Common chameleons use their coloration as a form of intraspecific communication. Females temporarily change their colors and patterns to indicate their reproductive status. Males change their colors and patterns to attract potential mates during mating season. When looking for a mate, females are green with two yellow lines. Females signal receptivity when they are looking for a mate or non-receptivity when they have already mated based on their body color. If they have already mated and are passively rejecting approaching males, they are green with yellow, orange, or green dots. If they have mated and are actively rejecting an insistent male, they turn black with spots that are yellow, orange, green, blue, or a combination of these colors. When females have already mated, they also ward off male suitors by performing a "dance", where they extend their legs, open their mouths and make cautionary hissing sounds. Once males find a mate, they become extremely territorial and aggressive towards other males. They follow their mate closely and stay within the home range of their mate until egg-laying occurs. (Cuadrado, 2001b; Cuadrado and Loman, 1999)
Mediterranean chameleons breed annually from July to September. They are oviparous and produce a single clutch per year. Females dig long and deep burrows in the ground to lay their eggs. Burrows are 52 cm long on average, with a nest chamber at the end that is an average of 36 cm wide. Females lay their eggs between October and November. They lay 14 to 47 eggs in each clutch, which incubate underground for 10 months. Hatching generally occurs in August, with hatchlings digging vertically out of their nest chambers. Hatchlings weigh 1.22 g on average. Roughly 96% of eggs survive to hatching.
Both sexes reach sexual maturity after about one year. Chameleons are the only squamates that exhibit embryonic diapause, in which embryos delay development until environmental conditions are suitable to enhance the fitness of the offspring. (Andrews, et al., 2008; Cuadrado, 2001a; Cuadrado, 2001b; Cuadrado and Loman, 1999; Keren-Rotem, et al., 2006)
Mediterranean chameleons exhibit limited parental investment. Females dig a burrow in which they lay their eggs, but do not exhibit any parental investment after their offspring hatch. Males exhibit no parental investment beyond the act of mating. (Cuadrado, 2001b; Cuadrado and Loman, 1999)
There is limited information regarding lifespans of wild Mediterranean chameleons. The maximum reported lifespan of a Mediterranean chameleon in captivity was 3.6 years. (Tacutu, et al., 2013)
Mediterranean chameleons are diurnal and spend their days foraging for food or basking in the sun. They are sit-and-wait predators and therefore are generally sedentary. Common chameleons are arboreal as adults and terricolous as juveniles.
Mediterranean chameleons are extremely territorial. Except during mating season, common chameleons live as solitary individuals.
During mating season, common chameleons communicate reproductive status and receptivity by changing color. (Cuadrado, 2001b; Cuadrado, et al., 2000; Keren-Rotem, et al., 2006; Pleguezuelos, et al., 1999)
Outside of mating season, home range size of Mediterranean chameleons is determined by prey abundance. Adults generally sleep in the same tree every night. During the mating season, the home range size of males is determined by the home range of the mate they are guarding, if any. Territory size ranges from 40 to 719 m^2 and averages 244 m^2 for both sexes. (Bartlett and Bartlett, 1995; Cuadrado, 2001b)
Mediterranean chameleons are solitary, except during mating season. They use coloration as a form of interspecific communication. Females temporarily change their colors and patterns to indicate their reproductive status, whereas males change their colors and patterns to attract potential female mates during mating season.
Mediterranean chameleons have distinctive eyes that are capable of working independently from one another. When moving, they use one eye to inspect the area in front of them while keeping an eye out for predators or prey elsewhere. When stationary, Mediterranean chameleons also use their eyes independently to scan the environment for predators and prey. Once they spot prey, however, both of their eyes focus on their target to improve depth perception and maximize their chances of a successful catch. (Bartlett and Bartlett, 1995; Cuadrado, 1998; Cuadrado, 2001a; Cuadrado, 2001b; Cuadrado, et al., 2000; Ligon and McGraw, 2013)
Mediterranean chameleons are insectivores, with a diet consisting of 88 to 100% arthropods. Common prey items include flies (order Diptera), hymenopterans (order Hymenoptera), true bugs (order Heteroptera), crickets and grasshoppers (order Orthoptera), and beetles (order Coleoptera). The majority of species in these orders are flying insects, although Mediterranean chameleons wait until their prey is stationary to catch them. Mediterranean chameleons consume prey in proportion to their abundance, and thus their diets can vary depending on the season and the insects that are available. For example, Mediterranean chameleons consume more grasshoppers and crickets in the summer and fall, when they are more abundant.
Mediterranean chameleons are sit-and-wait predators. They have specialized tongues, about as long as their bodies, which they use as projectiles to catch their prey from relatively large distances. Their tongues have numerous epithelial glands and papillae, which makes them sticky and improves the ease with which they can catch prey. (Herrel, et al., 2000; Hofer, et al., 2003; Pleguezuelos, et al., 1999)
Mediterranean chameleons have many natural predators, including snakes such as Montpellier snakes (Malpolon monspessulanus) and spotted whip snakes (Hemorrhois nummifer). Avian predators include kingfishers (family Alcedinidae), and birds of prey including common kestrels (Falco tinnunculus), short-toed snake eagles (Circaetus gallicus), and barn owls (Tyto alba). Mammalian predators include black rats (Rattus rattus), Norway rats (Rattus norvegicus), and small arboreal carnivores, such as beech martens (Martes foina). Of these predators, only snakes and rats hunt Mediterranean chameleons both on the ground and in trees.
Because urban and suburban development is encroaching on their natural habitats, domestic animals such as cats (Felis catus) and dogs (Canis lupus familiaris) are becoming larger predatory threats to Mediterranean chameleons. Adult Mediterranean chameleons are also known to cannibalize juveniles.
Mediterranean chameleons have cryptic coloration, which helps them camouflage with their environment to avoid predation. They also exhibit an ontogenetic habitat shift as they develop from juveniles to adults, wherein younger individuals use lower vegetative structures compared to adults. It is likely that this difference in habitat use reduces intraspecific competition and cannibalism. (Keren-Rotem, et al., 2006; Tacutu, et al., 2013)
Mediterranean chameleons help control populations of arthropods within their habitats and serve as prey items for multiple species of snakes, birds, and mammals.
Mediterranean chameleons are host for various parasites, including members of the flatworm genera Postorchigenes and Malagashitrema, which live in their large intestines. They are also hosts for protozoan parasites in the genus Hepatozoon, found in their bloodstream, and the protozoan Isospora mesnili, found in their small intestines. (al Saldoon and el Bahrawy, 1998; Herrel, et al., 2000; Modry and Koudela, 1995; Morsy, et al., 2012)
Mediterranean chameleons help control populations of arthropods, some of which can be agricultural pests. Thus, they potentially serve a role as natural pest control.
Mediterranean chameleons are traded internationally as part of the pet industry. Members of the genus Chamaeleo make up 42% of all chameleons exported. The majority of individuals are brought to the United States and sold in pet stores.
In North Africa, excluding Egypt, Mediterranean chameleons are believed to have medicinal, and sometimes even magical, properties. Traditional herbalists sell them in outdoor markets. In some cultures, women have traditionally fed their husbands chameleon meat because it was thought to restore fidelity. In Tunisia, people will kill a chameleon and bury it under their house to deter bad luck. (Carpenter, et al., 2004; Highfield and Bayley, 2020; Tolley and Herrel, 2014)
There are no known adverse economic effects of Mediterranean chameleons on humans.
Mediterranean chameleons are listed on the IUCN Red List as a species of “Least concern” and are listed under Appendix II on CITES, which regulates trade so as not to endanger the species. Habitat loss and illegal collection of animals are the main threats to Mediterranean chameleons. Habitat loss is primarily caused by urbanization, which is also associated with higher rates of predation by domestic animals and mortality on roads. Mediterranean chameleons are often gathered illegally and sold in the international pet market. Appendix II on CITES requires an export permit to be issued by the Management Authority of the State of export in order to trade Mediterranean chameleons internationally. They also must be shipped in a safe, humane manner.
In Spain, barriers have been built along roadways to reduce road-related mortality of Mediterranean chameleons. Other countries have not yet implemented such practices. (Vogrin, et al., 2012)
Carly Stevens (author), Radford University, Karen Powers (editor), Radford University, April Tingle (editor), Radford University, Emily Clark (editor), Radford University, Cari Mcgregor (editor), Radford University, Jacob Vaught (editor), Radford University, Galen Burrell (editor), Special Projects.
living in sub-Saharan Africa (south of 30 degrees north) and Madagascar.
living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.
uses sound to communicate
Referring to an animal that lives in trees; tree-climbing.
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
an animal that mainly eats meat
having markings, coloration, shapes, or other features that cause an animal to be camouflaged in its natural environment; being difficult to see or otherwise detect.
a period of time when growth or development is suspended in insects and other invertebrates, it can usually only be ended the appropriate environmental stimulus.
a substance used for the diagnosis, cure, mitigation, treatment, or prevention of disease
animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature
At about the time a female gives birth (e.g. in most kangaroo species), she also becomes receptive and mates. Embryos produced at this mating develop only as far as a hollow ball of cells (the blastocyst) and then become quiescent, entering a state of suspended animation or embryonic diapause. The hormonal signal (prolactin) which blocks further development of the blastocyst is produced in response to the sucking stimulus from the young in the pouch. When sucking decreases as the young begins to eat other food and to leave the pouch, or if the young is lost from the pouch, the quiescent blastocyst resumes development, the embryo is born, and the cycle begins again. (Macdonald 1984)
union of egg and spermatozoan
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
Animals with indeterminate growth continue to grow throughout their lives.
An animal that eats mainly insects or spiders.
referring to animal species that have been transported to and established populations in regions outside of their natural range, usually through human action.
offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).
having the capacity to move from one place to another.
the area in which the animal is naturally found, the region in which it is endemic.
reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.
the business of buying and selling animals for people to keep in their homes as pets.
having more than one female as a mate at one time
Referring to something living or located adjacent to a waterbody (usually, but not always, a river or stream).
breeding is confined to a particular season
remains in the same area
reproduction that includes combining the genetic contribution of two individuals, a male and a female
that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).
Living on the ground.
defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement
A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.
A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.
A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.
uses sight to communicate
Andrews, R., C. Diaz-Paniagua, A. Marco, A. Portheault. 2008. Developmental arrest during embryonic development of the common chameleon (Chamaeleo chamaeleon). Physiological and Biochemical Zoology, 81/3: 336-344.
Bartlett, P., R. Bartlett. 1995. Chameleons: Everything about Selection, Care, Nutrition, Diseases, Breeding, and Behavior. New York: Barron's Educational Series.
Carpenter, A., J. Rowcliffe, A. Watkinson. 2004. The dynamics of the global trade in chameleons. Biological Conservation, 120/2: 291-301.
Cuadrado, M. 2001. Body colors indicate the reproductive status of female common chameleons: Experimental evidence for the intersex communication function. International Journal of Behavioural Biology, 106/1: 79-91.
Cuadrado, M. 2001. Mate guarding and social mating system in male common chameleons (Chamaeleo chamaeleon). Journal of Zoology, 255/4: 425-435.
Cuadrado, M. 1998. The use of yellow spot colors as a sexual receptivity signal in females of Chamaeleo chamaeleon. Herpetologica, 54/3: 395-402.
Cuadrado, M., J. Loman. 1999. The effects of age and size on reproductive timing in female Chamaeleo chamaeleon. Journal of Herpetology, 33/1: 6-11.
Cuadrado, M., J. Martin, P. Lopez. 2000. Camouflage and escape decisions in the common chameleon (Chamaeleo chamaeleon). Biological Journal of the Linnean Society, 72/4: 547-554.
Herrel, A., J. Meyers, P. Aerts, K. Nishikawa. 2000. The mechanics of prey prehension in chameleons. Journal of Experimental Biology, 203/21: 3255-3263.
Highfield, A., J. Bayley. 2020. "Folklore, Myth and Exploitation of Reptiles in Morocco and Tunisia" (On-line). Accessed April 02, 2015 at http://www.tortoisetrust.org/articles/exploit.html.
Hodar, J., J. Pleguezuelos, J. Poveda. 2000. Habitat selection of the common chameleon (Chamaeleo chamaeleon) (L.) in an area under development in southern Spain: Implications for conservation. Biological Conservation, 94/1: 63-68.
Hofer, U., H. Baur, L. Bersier. 2003. Ecology of three sympatric species of the genus Chamaeleo in a tropical upland forest in Cameroon. Journal of Herpetology, 37/1: 203-207.
Keren-Rotem, T., A. Bouskila, E. Geffen. 2006. Ontogenetic habitat shift and risk of cannibalism in the common chameleon (Chamaeleo chamaeleon). Behavioral Ecology & Sociobiology, 59/6: 723-731.
Ligon, R., K. McGraw. 2013. Chameleons communicate with complex colour changes during contests: different body regions convey different information. Biology Letters, 9/6: 1-5.
Modry, D., B. Koudela. 1995. Description of Isospora jaracimrmani sp. n. (Apicomplexa: Eimeriidae) from the Yemen chameleon Chamaeleo calyptratus (Sauria: Chamaeleonidae). Folia Parasitologica, 42/1: 313-316.
Morsy, K., N. Ramadan, S. Al Hashimi, M. Ali, A. Bashtar. 2012. First description of the adult stages of Postorchigenes sp. (Trematoda: Lecithodendriidae) and Malagashitrema sp. (Trematoda: Homalometridae) infecting the common chameleon Chameleon chamaeleon (Reptilia: CHamaeleonidae) in Egypt. Life Science Journal, 9/4: 400-405.
Pleguezuelos, J., J. Poveda, R. Monterrubio, D. Ontiveros. 1999. Feeding habits of the common chameleon, Chamaeleo chamaeleon (Linnaeus, 1758) in the southeastern Iberian peninsula. Israel Journal of Zoology, 45/2: 267-276.
Tacutu, R., T. Craig, A. Budovsky, D. Wuttke, G. Lehmann, D. Taranukha, J. Costa, V. Fraifeld, J. de Magalhaes. 2013. Human ageing genomic resources: Integrated databases and tools for the biology and genetics of aging. Nucleic Acids Research, 41/D1: D1027-D1033.
Tolley, K., A. Herrel. 2014. The Biology of Chameleons. London, England: University of California Press.
Vogrin, M., C. Corti, V. Pérez Mellado, P. Sá-Sousa, M. Cheylan, J. Pleguezuelos, S. Baha El Din, A. Al Johany. 2012. "Chamaeleo chamaeleon" (On-line). Accessed February 05, 2015 at http://www.iucnredlist.org/details/157246/0.
Yaacov, D., K. Arbel-Thau, Y. Zilka, O. Ovadia, A. Bouskila, D. Mishmar. 2012. Mitochondrial DNA variation, but not nuclear DNA, sharply divides morphologically identical chameleons along an ancient geographic barrier. PLoS ONE, 7/3: 1-12.
al Saldoon, M., A. el Bahrawy. 1998. Blood parasites of five species of lizards trapped in Abha Province, Saudi Arabia. Journal of the Egyptian Society of Parasitology, 28/3: 899-905.