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[[Image:Anolis_carolinensis_mating.jpg|200px|thumb|right|'''Anoles mating''' (Wikicommons)]]
[[Image:Carolina_anoles_mating.jpg|300px|thumb|right|'''Two [[Green Anole|Carolina anoles]] mating''' (© Cowenby, Wikimedia Commons)]]
==Introduction==
Lizards have breeding seasons determined by cycles of photoperiod, temperature (most common), rainfall, and food availability. A corresponding fluctuation can be seen in male lizards and testicular size. Male lizards may also undergo [[Lizard Behaviour|behavioural]] changes during breeding season and become more territorial and aggressive.
Lizard reproductive strategies vary; they may be:
* '''oviparous''' - laying eggs (most lizards)
* '''ovoviviparous''' - the eggs are retained within the female until birth of live young (all [[Monitor|monitors]], most iguanids, [[Water Dragon|water dragons]], all geckos, most [[Chameleon|chameleons]])
* '''viviparous''' - live-bearing, with a placental type of circulatory connection (blue-tongued skinks, [[Stump-tailed Skink|shingle-backed skink]], [[Prehensile-tailed Skink|prehensile-tailed skink]], [[Chameleon|Jackson's chameleon]])
* '''parthenogenic''' - asexual reproduction found in lizards such as certain ''Lacerta'' spp. and whiptail lizards (''Aspidocelis'' [''Cnemidophorus''] spp.) consisting entirely of females. Although they reproduce asexually, these females still show courting and pseudocopulation.
Parthenogenesis has been reported in about 30 species of lizards.
==Sexual Maturity==
Sexual maturity in reptiles is mainly determined by size. Standard ages of sexual maturity found in the literature usually apply to free-ranging animals. However in captiivty, environmental conditions, care and most importantly diet vary dramatically, resulting in reptiles becoming sexually mature at very different ages. As a reference and rough generality, small lizards take 1 to 2 years and large lizards 3 to 4 years to reach sexual maturity.
==Temperature-Dependent Sex Determination==
A few species of lizards, such as the [[Leopard Gecko|leopard gecko]] (''Eublepharis macularius'') have temperature-dependent sex determination where the sex of the developing fetus is determined by the temperature at which the eggs are incubated. The exact temperatures are species dependent; however the shift from one sex to the other is not absolute. A range of temperatures exists at which both sexes are produced at varying proportions and therefore most incubators used by breeders are not accurate.
* Mader, D.R. (2005). ''Reptile Medicine and Surgery''. Saunders. pp. 1264. ISBN 072169327X
* Mader, D.R. (2005). ''Reptile Medicine and Surgery''. Saunders. pp. 1264. ISBN 072169327X
[[Category:Lizard Physiology|R]]