Do we have hot blood if it's a huge waste of energy
I know it's going to sound weird, but there are times when I find myself twisting the pros and cons of becoming a being from the underworld. I don't know, think about it: little brown that a werewolf bites you. Beyond the subject of wild pains that a mass of hundreds of kilos gets embedded in your thigh and makes you an ecce homo in your leg, the process of transforming into a bug must be the worst.
The problem is that there is no good infraser: the process of ‘zombification’ requires that a hungry horde of undead open your brains and pay tribute to each other that neither Caligula in his good times. To be a witch, for example, you need to come to some kind of shady deal with the Devil. Something that sounds good if you do not realize that Hell must be the closest thing in the world to unsubscribe from an operator.
There is more: the theme of 'souls in pain' and ghosts is bad business because you need a good curriculum full of killings, Varg Vikernes posters and other things of relaxed morals to be roaming the world without rhyme or reason throughout the eternity. That yes, fixed place that is not no nonsense either. In the end, I always end up convinced that the only reason for vampire success is, ultimately, competition. Lack of it, I mean.
But to me, if I'm honest, the vampires didn't convince me either. I can tolerate the obsession with carotids and even convince myself that going all day smeared with factor 50 cream has its point. So I do not pass is why drinking hot blood. What good is 500 or 600 more years if I have to take two liters of warm blood a day? Are you sure it's not worth it with a black pudding skewer? Why does it have to be hot?
The fascinating world of homeostasis
And it turns out it's an excellent question. Why are some living things "hot blooded" and others not? Think about it for a moment: heating all that amount of blood (and, by extension, all metabolism) takes a lot of energy. Estimates say that organisms with thermal homeostasis require ten times more resources than those without.
The figure that fifty antelopes is enough food to feed one lion or ten crocodiles is well known. Honestly, I have not been able to find the specific reference (and I do not think it is exact), but it serves to visualize the proportions we are talking about. Does all this hot blooded stuff make sense?
But, as I say, it is only a striking explanation. Actually, you don't have to resort to that to explain the main benefits (and problems) of having hot blood. The advantage of homeothermy is that it allows the body to always be at a temperature where biochemical reactions work optimally.
Or close to optimal. But as the saying goes, there are times when "the best is the enemy of the good." Keeping this type of machinery ready makes us very sensitive to changes in ambient temperature or lack of food. Being cold-blooded makes it easier to survive in the painful conditions in which most living things live.
Cold-blooded and warm-blooded are rather two points on a spectrum where each degree of complexity and power also carries with it a degree of fragility. There are many intermediate points with fish capable of heating part of their body and mammals that sleep all winter. Something fascinating in itself, but the most curious explanation on the subject is another.
There are theorists who believe that homeostasis is a defense against fungal infections. Insects, reptiles, or amphibians are riddled with fungi; on the other hand, most infections of this type have great difficulty in surviving the temperature of warm blood. It is, what doubt, a good reason not to drink things from cold-blooded animals. Vampires know them all.