Bee mystery

This morning when I left for work, I noticed approximately ten honeybees sitting, motionless, on the inside of the closed garage door. It was the first time I had seen bees in the garage and I was worried they might be swarming in the roof or something since it didn’t seem likely that all of them had gotten in by accident, but there was no swarm that I could see; just ten motionless bees. I left them there and went to work.

When I came home this evening, the bees were no longer on the garage door. I thought they must have flown away until I noticed a dead bee on the ground. Looking closer, I found another, and another, and another. In all, I counted twenty-five dead bees on the ground, and one that was still alive and standing but barely moving.

There are two mysteries here:

  1. Where did the twenty-six bees come from?
  2. What killed twenty-five of them and left one virtually paralyzed?