Earthworm castings

I noticed some pellet-like formations while doing a bit of weeding:

I thought it was the action of ants, but it didn’t quite look right. Apparently, it’s worm poo (“castings”).

It feels like I may be the last person on earth to have not already known this. It even looks like it had a lot of coverage in The Formation of Vegetable Mould Through the Action of Worms by one Charles Darwin.