Why Is My Body Temperature 37 Degrees?
If you force out a measuring device and took your temperature without delay, youd most likely get a reading of around thirty seven degrees Celsius. That variety could vary a bit from day to day, or perhaps hour to hour, however overall your blood heat is pretty consistent. If you get too hot, your blood vessels can expand, and youll sweat to chill down. If you get too cold, your blood vessels can contract, and youll shiver to heat up. And if you stray over a few degrees in either direction — like with a very unhealthy fever or in cooling weather — your proteins and cells close up, and you may die. therefore why is thirty seven degrees the magic number? Why not thirty five or 40? Well, one major theory suggests its all concerning keeping out flora. Scientists have found that bound animals, like reptiles and amphibians, get plenty of various fungous diseases.
And theyre all ectotherms — they depend on external heat sources to stay warm. Specifically, they get way more fungal infections than their endotherm counterparts, like mammals, which generate body heat internally. Researchers from Yeshiva University wanted to find out why. They tested the heat tolerance of different species of fungus, starting at a temperature of 30 degrees Celsius. And found that every one degree increase in temperature caused a six percent decrease in the number of fungal species that are able to infect an animal host. So if youre a frog depending on sunlight to warm you up, youve gotta worry about tens of thousands of fungal species that can infect you and cause life-threatening disease.
But if youre a mammal hovering around 37 degrees, only a few hundred fungi can survive long enough to mess with you. In other words, when it comes to the risk of fungal infection, it really helps to be hot. Then again, you dont want to be too hot. After all, it takes a whole lot of energy to maintain a high body temperature, and you dont want to spend all your time finding food and eating it. You want to find a perfect balance. And guess what? When these researchers ran some mathematical models, weighing the benefits of protecting against fungi versus the costs of extra food consumption, they calculated an ideal body temperature of 36.7 degrees Celsius. Which is right around our toasty 37 degrees. In fact, these scientists even think that maintaining this warm body temperature helped mammals thrive as the dinosaurs went extinct, even though its energy-intensive.