Remember the Gene Wilder/ Marty Feldman exchange from that great Mel Brooks classic, Young Frankenstein? There was a time in folklore that werewolves were feared hiding behind every tree. No more.
A theory by a member of the British Society for the History of Science proposes that the reason werewolves have, for the most part, died out in folklore is because of Charles Darwin. Following his publication of his Origin of Species in 1859, Brian Regal says "the spread of the idea of evolution helped kill off the werewolf because a canid-human hybrid makes no sense from an evolutionary point of view."