Ants

A smaller species of Ant (at about 3 mm in length) nesting underground in sandy soil. There was a cleared area around the nest opening, but no mounding. Interestingly, as I was photographing them, instead of becoming more numerous and aggressive, they began to close up the entrance hole and disappear! See the sequence of photos taken within about 2 minutes. That was a new one for me. Wouldn't it be nice if all species did that?