Hmmm.. his assumption is that vampires need to feed on a new human each time and that each time they do, they would create a vampire.

But what if the vampire broke the victims neck first, then sucked the blood or drained it out and stored it for a while. Each body has how many liters of blood? Assuming that a vampire only needs a shot or something small to survive, 1 person could go a long way.

The other option is the vampire captures several humans and keeps them prisoner and just drains a little blood every week - sort of like the Red Cross does. Then the human would last longer until they were either killed or turned into a companion vampire.

Then real question I think this p...

Hmmm.. his assumption is that vampires need to feed on a new human each time and that each time they do, they would create a vampire.

But what if the vampire broke the victims neck first, then sucked the blood or drained it out and stored it for a while. Each body has how many liters of blood? Assuming that a vampire only needs a shot or something small to survive, 1 person could go a long way.

The other option is the vampire captures several humans and keeps them prisoner and just drains a little blood every week - sort of like the Red Cross does. Then the human would last longer until they were either killed or turned into a companion vampire.

Then real question I think this prof. should ask is how many vampires are needed in order to capture how many humans that could become their food supply for years, etc. There has to be a break even factor there and a logistics factor.

Anyway -- I think his logic is flawed. Not saying there are or there are not vampires, but one never knows.