Fauna of Scotland
Only six amphibians and four land reptiles are native to Scotland. The amphibians include three species of newt: the great crested, of which fewer than 1,000 individuals survive; the smooth, and the palmate. The other amphibians are the common toad, the natterjack toad, found in only four locations in the south-west, and the common frog. A single alien amphibian is known in Scotland, the Alpine newt, a recent escapee confined to the Edinburgh area.
Italian crested newt
Temperature in amphibians and reptiles directly affects metabolism in an exponential manner, and among ectotherms, temperature is one of the most important factors, acting directly upon metabolism. Since the newt is a poikilotherm, the purpose of this increase in metabolism is not to generate heat to regulate their internal temperature, but to counteract the depressive effect on standard metabolism that low atmospheric temperatures produce. For example, there is a direct correlation between the activity of certain muscle metabolic enzymes and the preferred body temperature of Eastern red spotted newts.