A question I get asked a lot by skeptics is "Well what happened to the (insert Elves, Vampires, Giants, whatever) then?"
Yeah, there's a reason human history seems to have this massive, gaping hole in it. Humans are the binder by which all races preserved their standing on this planet. Did the Elves sail off into the eternal light? Were Vampires hunted into extinction? Maybe. But one things as clear as crystal, they didn't leave the planet. Not really.
For more info read my article You Are Not Human
People say there were several types of humans on the planet. Well, i guess you could say that. Several different mediums & one medium proved better than them all. The structure you're walking around in today.
Mating with this medium proved a welcome host for different types of genetic codes. There's obviously no flawless system because the medium was not divine. But, it was the human binder that could take the variations in genetic profiles & make a new strain of DNA.
The power of the human foundation, the human medium, became the saving grace through which all species could leave a longer-lasting fingerprint on life. I don't say an "eternal" fingerprint because let's be honest, every species known to have ever walked, swam, or flown on this planet has come to an end, & humans will too.
It's interesting in the 21st century that despite all evidence to the contrary, science still tries to fit everything in this post-spiritual, logical box. Some people say magick is simply a scientific phenomena not explained. However, it's quite the opposite; science only explains what magick is. If they would expand their minds a little & look back into history, & more importantly, look back into the giant voids of humanity in the millions of years of history, they might scratch the surface of something really interesting - what happened to all the species before humanity took over.