Moving House.
Did you notice that ring on the top of the storage space to the right of my poinsettia photos? If so, you might have been curious about what it was. Not just a ring of dirt from where I moved the pot. This is what was going on! It reminds me of humans evacuating a hospital before a hurricane or after a disaster. And yes, I did feel a bit guilty. But it looks like their backup plan worked just fine. (Click on the first photo to enlarge photos and read captions.)
But eventually, all had relocated in the light sconce above. When I went out six hours later, all was still. Not a sign of a tiny ant or egg, until I turned over the pot from the location I had moved it to. About 50 of the ants had re-relocated back to their former home. When I turned the pot sideways, they scurried around like mad, grabbing their assigned eggs and making off again. Hurriedly, I set the pot back down again. No time for a photo this time.