First you must realize that cats do not feel heat the way we do.
A cats body temperature is 102 degrees which is much warmer that our 98.7 degrees.
Cats also have fewer heat receptors than we do. While we feel pain at a temp of 112 degrees a cat won't feel pain until it reaches 126 degrees which is why cats get burned more easily. They will lay too close to a fire or walk on a hot stove.
The breed of a cat makes a difference too. Different breeds are more tolerant of cold. Breeds like the Maine Coon with their thick fur coat helps to keep them warmer than other breeds.
Also the age of a cat can determine how warm they need to be. Newborns cannot produce enough heat on their own and therefore depend on the mother cat for warmth. Newborns have a keen sense of temperature using the receptors on their face. This allows them to find the mother cat while their eyes are still closed. This is why you must provide warmth to kittens who have lost their mother. Kittens that are too cold will not eat or thrive.
Illness will also change a cats heat seeking behavior. While some illnesses cause cats to seek out cooler spots than normal others will cause them to find warmer than normal places. It is very important to observe your cats behavior and if there are any changes you should contact your veterinarian.
It is also helpful to understand the origin of the cat to get a better idea of why they seek warmth.
Desert cats bodies are built to throw off heat with their long bodies and short hair while colder climate cats have longer hair and shorter stocky bodies.
Cats are mammals which means they use a certain amount of fuel to heat their bodies. Almost a third of their fuel is used to maintain their skin and fur.
Cats will conserve energy by using the solar energy of the sun to stay warm. You will see them follow the sunlight as it inches across the room. This odd behavior offsets the body's drop is basal metabolism that occurs with sleeps shutdown of certain body processes.
It doesn't necessarily have to be the sun, but any warm place such as under a lamp or next to a fire, on a car hood or even under the car in the motor which you must be extremely careful of as many cats get killed in the fan when the car is started for this reason.
This heat seeking behavior allows a cats body to not work as hard to stay warm while napping.
So while your cat may baffle you at times with his odd behavior remember it is serving a much needed purpose.
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