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''Ctenophorus decresii'', also known as the Tawny Dragon, is a species of lizard commonly found in Australia. They are a member of the Ctenophorus genus of lizards, which is a very diverse group of lizards found throughout the world. The entire genus of lizards is sexually dimorphic. Neck and overall coloration distinguishes male lizards from female and juvenile lizards. Most often C. decresii are found in rocky areas throughout Australia. However, their habitat varies as they are found in a few distinct locations throughout Australia.〔 Scientists have identified the different populations of lizards as separate lineages due to their geographic isolation.〔 The three lineages of C. decresii are the northern, southern, and NSW lineages. The entire Ctenophorus genus maintains a generally constant body shape, adapted for the Australian climate. == Polymorphism == Ctenophorus decresii is known to display polymorphism, or express different forms within the species, in their throat coloration.〔 Within the species of ''C. Decresii'', the throat morphs can range from grey and white to a bright red.〔 ''C. decresii's'' diversity in throat color may be caused by a combination of sexual selection and natural selection. The ''C. Decresii'' lizard throat colors can be classified into two categories—dull and bright colored.〔 The dull colored throats give lizards a fitness advantage because the lizards are harder for predators, like birds, to see.〔 The dull throats allows the lizards to avoid predators and survive longer; therefore, this trait became more prevalent in that population of lizards.〔 However, bright colored throats also give the lizards a fitness advantage because the bright colored throats attracted more females, and therefore those males were more likely to reproduce.〔 Although the bright colored throats increased the likelihood of being eaten by predators, it also increased their sexual success.〔 Therefore, the prevalence of bright colored throats also increased in this population of lizards.〔 It is understandable why the diversity of throat coloration of lizards has been maintained for many generations. Both traits give the lizards a different evolutionary advantage. Looking at a larger sample of ''Ctenophorous decresii'', more variation in throat color can be found.〔 Some of the variants found throughout the world include multi-colored, grey, yellow, orange, blue and red throated lizards.〔 This variation comes from the diverse geographic locations ''C. decresii'' can be found in, such as, South Australia, New South Wales and other areas throughout Australia.〔 One geographic location may favor a certain throat color for ''C. decresii'', while a different location may prefer a different color.〔 Because ''Ctenophorous decresii'' are found in distinct geographic locations, there are separate, unique lineages of the ''C. decresii''. The color variants in the ''Ctenophorous decresii is'' discrete, meaning individual lizards morphology could be placed into specific categories 〔 After using objective methods to identify the color morphs, statistical tests were run.〔 The tests analyzed variation based on granularity, segmentation, and comparison with visual background.〔 One group of lizards had similar granularity, segmentation, and coloration.〔 Another group also had similar granularity, segmentation and coloration that differed from the first group. There were very few lizards with in between phenotypes.〔 However, within the categories, there still is slight variation in the shades of colors of the lizards. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Ctenophorus decresii」の詳細全文を読む スポンサード リンク
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