AP BIOLOGY

Detailed explanation-1: -Ectotherms depend mainly on external heat sources, and their body temperature changes with the temperature of the environment. Animals exchange heat with their environment through radiation, conduction-sometimes aided by convection-and evaporation.

Detailed explanation-2: -Ectothermic animals develop faster at warmer temperatures [1], and they usually mature at smaller body sizes-as much as 20 per cent smaller for a 10°C temperature increase. This phenomenon has been called the ‘temperature size rule’ (TSR) [2].

Detailed explanation-3: -ectotherm, any so-called cold-blooded animal-that is, any animal whose regulation of body temperature depends on external sources, such as sunlight or a heated rock surface. The ectotherms include the fishes, amphibians, reptiles, and invertebrates.

Detailed explanation-4: -Despite most ectotherms exhibit behavioural plasticity that allows them to adjust their body temperature to environmental conditions, rising temperatures can put ectotherms outside their physiological optima and closer, or even above, their thermal tolerance limits (Kingsolver et al., 2013; Sunday et al., 2014).

Detailed explanation-5: -In contrast, ectotherms rely on behavior to regulate their body temperature. They must move their bodies into the shade or sun to cool down or warm up. This requires less energy than constant metabolic regulation. This is why many reptiles and other ectotherms can eat one large meal and not eat again for some time.