springtail poop lattice construction

I noticed this interesting behavior by some springtails in one of the moist chambers I put together for trying to germinate wild slime molds.

 

The springtails are a small white isotomid that appear at first glance a bit like a Folsomia, but they don't have the combined abd4-6. And they have at least 2+2 eyes from what I've been able to see.

 

I had noticed these springtails there a day or two prior, and noticed that they seemed to stay in the cracks and crevices in the piece of wood. So I sprinkled a few grains of baker's yeast in the area for them.

 

And then tonight, when I was checking back in on them, I was surprised to find multiple pieces of lattice work near the yeast grains, and I could see the springtails moving behind the lattices.

 

I watched one closely for a while, and saw that it would probe at the lattice with its butt, and would eventually find an opening and stick its butt through, then extend the existing lattice by placing a fecal pellet.

 

They seem to construct a lattice wall, sealing off the crevice opening, near the food.

Done