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Part of the Anatomically Correct Series.
I think we’re all familiar with the traditional vampire: pale skinned, blood suckers that drink blood through their fangs and have an aversion to sunlight and garlic while also resembling humans. Could something like this evolve in nature.
P.s.: In this scenario, let’s just assume that these vampires are their own species rather than a human being transformed by another vampire.
Humans are Terrible Neighbors
The problem with super predators is that humans are terrified of them. When humans are terrified of something it typically goes extinct. Think about it for am minute, in the ice age there were a TON of massive super-predators dragging our ancestors off into the night for a snack. There's a very practical reason behind why those animals aren't around anymore, and why the ones that are left instinctively fear us. Because we are the scariest thing on this planet, and we wont let anything compete with us for that title. We wiped anything out that could with stone age tools and fire. Humans have an unsettling pyromaniacal fascination it comes to dispatching monsters, we are obsessed with burning things to death on an almost instinctive level. In the eyes of everything else on this planet we are psychotic swarming pack hunters with a near magical control over the elements. Not much room for anything competing to coexist.
My personal theory is that vampires as a sub-species would need to look as much like us as possible and perform as stealth/ambush predators, because the moment something that looks like a giant fanged bat-monkey with glowing eyes crawls into somebodies village and starts popping open arteries literally any humans within 10 miles are now sharpening up their pointy sticks and lighting their torches. The big-nasty might really do a number, it might even chase the humans off a few times. But they wont. stop. coming. Vampires would also have to be a very low-population species because with humans as their primary food source they could never exist in large numbers without either eating themselves to starvation, or triggering humanity's ire and being run off or slain. Simply put, humanity is a very dangerous prey item as a whole.
So they exist in very very small numbers, they look like us, and they are every bit as intelligent as us. Since numbers are small they breed only rarely and thus have adapted very long lifespans to compensate. Not immortal mind you, just much longer than a human, a few centuries perhaps. In this manner they are able to still mate several times a lifetime despite only making up maybe 1% of the total population that humanity has. As for fangs, why need them? they just telegraph your otherness to humans, anyone that sees somebody with fangs will be alerted that something is wrong and guess who is being burned at the stake when bite marks show up on dead bodies and you are the only fella with a set of matching teeth in town? The Vampires are like us, they use tools to harvest their resources. Serial killings, missing persons, those are all just (mostly) vampire attack victims.
That is not to say that vampires are just blood thirsty humans. They do need to be able to distinguish between each-other and fellow humans somehow, if for no other purpose than to find a mate. They posses a highly refined sense of smell so they can seek each-other without any identifying features that arouse suspicion in humans. Also, as solitary ambush predators they need to be able to attack when prey is vulnerable but also ideally out of sight of other humans as well. This means they hunt and feed primarily at night, and posses better hearing and night vision than most humans. Not extraordinarily better like a cat or something, just a bit better than their prey. Their digestive tracts are vastly simplified,they only need to digest one food source after all. This means that instead of huge stomachs and yards and yards of intestines they just really need a very simple digestive tract, the rest of their body cavity is actually a fat-reserve so they evolved to have so that they don't give away their otherness with a waspish concave or emaciated looking belly. These fat deposits actually insulate organs and make it noticeably more difficult to mortally wound a vampire than a human (again, not supernaturally, just noticeably so.) They not only exist in very small numbers, but only feed rarely (if too many bodies show up too often somebody will sound the alarm and start hunting the hunter after-all.) The rest of the body cavity not used by these hidden fat reserves is taken up by a slightly larger set of lungs and a heart that beats much faster than a humans. Vampires posses far more twitch fibers in their muscle tissue than humans do giving them intense bursts of speed and explosive strength but only for short duration's. An average vampire can out-sprint and out-fight a human in outright hand to hand combat, but if the initial explosive assault is weathered the human can win with either long distance running, or wrestling.
Now, all of this falls apart for our blood sucking cousins when modern medical technology comes about. Human's being the curious psychotics that they are seem to enjoy poking around inside of dead stuff just out figure out how it works, eventually somebody would discover that a portion of humanity aren't really humans at all. Now you got humans with both guns and napalm getting pretty irate about the fact that they have a trespasser in their society. Could make for some pretty impressive (possibly catastrophic) culture shock.
There are many examples in nature of parasitic organisms. These organisms evolve as a permanent or temporary attachment or exchanging relationship with the host organism, usually at the hosts expense. They could evolve out of a standard predator relationship (such as mosquitos and flies), or a more complex semi-symbiotic relationship (such as gut bacteria and/or mistletoe).
By the way, such relationships evolve in all Kingdoms, Animal, Plant, Fungus, Protozoic and bacterial.
So functionally - vampires could be argued to be quite common in all taxonomic ranges.
However, if you're thinking more of attributes like depicted in film, then apart from the functional aspect of a vampire we can look at each attribute specifically:
pale skinned: Yes, there are many examples of albino / unusually pale humans. Usually there is a genetic error in melatonin production that causes unusually white skin, however generally people from cold environments usually have white skin as melatonin is not useful in cold climates (and can actually be detrimental)
blood suckers: Well, we are omnivorous. Blood can obviously be a source of sustenance for people, we do eat meat which has blood content. Will it be enough to sustain you? A healthy diet of fruit and vegetables we know is required to prevent diseases such as scurvy - however there are creatures (such as mosquitos) that do exist only by consuming blood, so there must be nutrients enough for them to exist.
aversion to sunlight: Currently sunlight is not harmful to us as humans, although there are many animals that are nocturnal, to suit an evolutionary niche and for protection, as nighttime is a generally safer period to be outside due to low light levels.
aversion to garlic: Well - garlic is a part of a plant, the smell it makes is essentially a chemical, so there may be some allergies associated with it. So yes - this is possible too.
Probably the largest barrier to vampires is simply that they would be quite unpopular by us humans - plus it's hard to integrate into a modern society whilst trying to suck someone's blood, it may be frowned upon and it may be easy nowadays simply to have a burger, work shiftwork, get an artificial tan, and avoid garlic.
