Vampires real or not?

The truth is evolution hasn't allowed more than one predator to rule for more than a few thousand years at a time. So what makes us think that we are still the "top" now for all we know vampire's are real created because humans have spread and populated the entire planet so in theory there has to be something out there that hunts us with out us knowing about it. The truth is there are thousands of species of creature found each and every year and more out there that is undiscovered so maybe there are vampires. All we have is stories and they all had to start from somewhere so maybe they dont exist but maybe just maybe they do.