What is the difference between animals that are Endotherms and Ectotherms?
What is the difference between an ectotherm and an endotherm? Ectotherms, including reptiles and amphibians, are organisms that don't possess the ability to generate sufficient heat to keep themselves warm. Endotherms, in contrast, do possess the ability to generate their own body heat.
One way that ectotherms may increase their body temperature is to seek out heat sources. Reptiles are a great example of this. Snakes, turtles, lizards, and alligators are all examples of animals that use the sun to warm themselves.
- Alligators are “cold-blooded,” meaning that they are ectothermic animals that cannot regulate their own body temperature, but assume the temperatures of their surrounding environment. To warm themselves, alligators bask in the sun, which is when they are frequently observed on the banks of water bodies.
- A conformer is also called an ectotherm. A conformer cannot regulate its own internal temperature so it must adapt its behavior, physically moving itself to environments with optimum temperatures. Reptiles, amphibians and insects are all conformers and are often referred to as cold blooded.
- Sea Turtles. There are relatively few reptile species that have adapted to the challenges of the marine environment. Unlike mammals, most reptiles cannot maintain a constant body temperature (endothermic); their body temperature changes with the environment around them (ectothermic).
The two extremes in the animal kingdom are endothermic homeotherms and ectothermic poikilotherms. Most mammals, including humans, as well as most birds are endothermic homeotherms, while most fish, invertibrates, reptiles, and amphibians are ectothermic poikilotherms.
- The five most well known classes of vertebrates (animals with backbones) are mammals, birds, fish, reptiles, amphibians. They are all part of the phylum chordata -- I remember "chordata" by thinking of spinal chord.
- Ectothermic animals are often known as cold-blooded although this is a misnomer as the body fluids are usually warm. Reptiles are one of the usually cited examples of ectothermic animals but insects and other arthropods are also ectothermic.
- Thermoregulation in organisms runs along a spectrum from endothermy to ectothermy. Endotherms create most of their heat via metabolic processes, and are colloquially referred to as warm-blooded. Ectotherms use external sources of temperature to regulate their body temperatures.
Updated: 2nd October 2019