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The Italian crested newt (''Triturus carnifex'') is a species of newt in the family Salamandridae. ==Habitat== ''Triturus carnifex'' is found in parts of the Balkans and Italy. It is an aquatic breeder that can spend up to four months in the water.〔(Arntzen, J.W., Themudo, G.E., Wielstra, B. 2007. The phylogeny of crested newts (Triturus cristatus superspecies): nuclear and mitochondrial genetic characters suggest a hard polytomy, in line with the paleogeography of the centre of origin. Contributions to Zoology 76(4):261-278.)〕 The location of the ponds where they breed affects the time when ''T. carnifex'' enters the water.〔 ''T. carnifex'' prefers living in deep water since it is a nektonic species: it swims freely and is independent of currents.〔 The absence of predatory fish may also explain why ''T. carnifex'' is inclined to ponds, rather than other larger bodies of water.〔 They typically prefer ponds in northern Europe, where temperatures are colder. Adult ''T. carnifex'' start to arrive between February and May, and leave between July and October.〔(Andreone, F., and Giacoma, C. 1989. Breeding Dynamics of Triturus Carnifex at a pond in Northwestern Italy (Amphibia, Urodela, Salamandridae). Holarctic Ecology 12:219-223.)〕 In warmer ponds, adult newts arrive within a month and leave during a two-week period in July.〔 Andreone and Giacoma (1989) speculated that newt migration into the ponds increases after rainy days, since after rainfall, newt activity is not limited by humidity. Higher altitudes, where temperatures begin to decrease, have a direct effect on the size of ''T. carnifex''.〔(Ficetola, G. F., et al. 2010. Ecogeographical variation of body size in the newt Triturus carnifex: comparing the hypotheses using an information-theoretic approach. Global Ecology and Biogeography 19: 485-495.)〕 Ficetola et al. (2010) discovered that living in colder temperatures resulted a body size increase in both male and female. Females in higher altitudes were found to be larger because they were carrying more oocytes and larger ovaries, which gave them a reproductive advantage over the smaller females.〔 ''T. carnifex'' is poikilothermic and larger body sizes help to reduce heat fluctuations.〔 Ficetola also found that fluctuations in body temperature of T. carnifex decreased when body size increased. An increase in body size also occurs where there is increased precipitation or nearby primary producers, due to the effect of increased resources on animals.〔 Human interference has dramatically changed the habitat of ''T. carnifex'' due to the expansion of industrial areas and urban centers.〔(Ficetola and Bernardi 2003)〕 This results in a fragmentation of natural landscapes, which leads to selective extinction, genetic drift, and inbreeding from isolation.〔 Introducing fish to isolated wetland habitats also leads to a decline of amphibians because of predation on newt larvae.〔 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「Italian crested newt」の詳細全文を読む スポンサード リンク
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