The idea one of the preceding comments seemed to imply was that they sample a bit first. > I felt it go into my skin and watched it suck for a bit, but it didn

The idea one of the preceding comments seemed to imply was that they sample a bit first. > I felt it go into my skin and watched it suck for a bit, but it didn't get particularly engorged on it. No mark the next day. So it might follow that with one resistant (R) and one non-resistant person (NR) exposed to a few dozen mosquitoes, NR will end up with lots of visible bites while R will be relatively unscathed - even though the mosquitoes might have sampled them each equally. I know too that some mammals (e.g. mice) will sample a small amount of food (e.g. rodent poison), and then return later to try more if the food hasn't had ill effects. I'm not sure that mosquitoes have anything like a memory capacity for this, but maybe something similar mediated via pheromones could be happening. (And something like pheromones could also signal to other mosquitoes that there's good eatin' to be had).