külmaverelisteks

Külmaverelisteks refers to ectothermic animals, commonly known as cold-blooded creatures. This term describes animals whose internal body temperature is largely dependent on their external environment. Unlike endothermic animals (warm-blooded), they do not generate significant metabolic heat to maintain a stable body temperature. Instead, they rely on external sources such as sunlight, warm surfaces, or warmer water to regulate their body heat.

This physiological characteristic impacts their behavior and habitat. For instance, reptiles, amphibians, fish, and invertebrates are all examples of ectotherms. Many of these animals bask in the sun to warm up, seek shade or cooler water when too hot, and their activity levels often fluctuate with ambient temperatures. In colder climates, some ectotherms enter a state of dormancy, like hibernation or brumation, to survive periods of low temperatures.

The term "cold-blooded" is somewhat of a misnomer as their blood is not necessarily cold; it simply varies with the environmental temperature. However, the descriptive term "ectotherm" is scientifically preferred for accuracy. Ectothermy allows these animals to survive on less food compared to endotherms of similar size, as they don't expend energy maintaining a high internal temperature. This adaptation is prevalent across a vast array of species and plays a crucial role in their ecological niches.