Humans can live in areas that get cold because we are warm-blooded. We can keep our body temperature about 98.6 degrees F all of the time.
All animals are either cold blooded or warm blooded. The difference between whether an animal is cold or warm blooded comes down to whether or not that animal can control its internal body temperature by itself.
Whether or not an animals is cold blooded or warm blooded has nothing to do with the actual temperature of its blood. Instead it comes down how that animal keeps its internal body temperature the correct temperature for it to survive. Throughout the season and even day the outside temperature changes a lot. Despite that animals keep their internal body temperature within their acceptable range.
Humans Notice A Small Change In Internal Temperature
Just to put this in perspective I wanted to talk about us, humans first. Whenever you check your temperature with a thermometer you can check if you have a fever and are sick or if you are normal. Normal temperature for humans is 98.6 degrees F. If you temperature goes up to 99 or 100 degrees F you definitely notice it and don’t feel well. That is only a change of less than two degrees and our entire body feels it!
What does it mean to be warm blooded?
Animals that are warm blooded are able to regulate their own body temperatures. This means that those animals do not need to do anything special if it gets warm or cold outside in order to keep their body at their normal temperature. Warm blooded animals change the food they eat into energy, some of which they use to keep their bodies the correct temperature.
Raccoons are warm blooded and can live in the snow.
If warm blooded animals are too cold then they use some energy to warm themselves up, and if they are too hot they cool themselves off by doing something like sweating or panting. All of this warming up and cooling off of their bodies means that these animals need to eat more food than cold blooded animals because it takes a lot of energy to keep a constant body temperature.
One good thing about being a warm blooded animal is that these animals can be active anytime no matter what the temperature is outside as long as they have enough energy. This allows them to live just about anywhere in the world and to be active during winter!
Endotherm
The scientific name for warm blooded animals, meaning animals that can regulate their own body temperature is endotherm. Some common warm blooded animals or ectotherms are mammals and birds.
What does it mean to be cold blooded?
Cold blooded animals can’t maintain their own body temperature, instead they become the temperature of their surroundings. If it is cold outside, their bodies become cold and if it is hot outside they become hot.
If a cold blooded animal becomes too cold they need to go sit in the sun to warm up. This is one reason you will often see lizards sitting in the sun. Or if they are too hot they need to seek shade or a cool spot to cool themselves off.
Since cold blooded animals body temperature is changing their activity levels also change a lot. When they are cold they become less active and sluggish, but when it is warm out they are more active. However, if it becomes too hot that is also not good for them.
The difference in their activity level is because their muscles work faster when their body is warmer. Cold blooded animals do not live in high mountains (such as high up in the Rocky Mountains) because it is just too cold there and they can’t survive since their bodies are too cold and inactive to get food.
Snakes are cold blooded and need to lay out in the sun to warm up and become active.
One good thing about being cold blooded is that these animals do not need to eat as much food as warm blooded animals. This is because they do not need to use lots of energy just to maintain their body temperature like warm blooded animals do.
Ectotherm
The scientific name for animals that can not maintain their own body temperature is ectotherm. Some common cold-blooded animals or ectotherms are reptiles, fish, amphibians, and insects.