Small hermit and soldier crabs in Malaysia and Australia build their home digging deep holes in the sand on a beach. Down in the hole the crabs make sand balls that are pushed to the surface, 2-3 balls at a time, forming a kind of sand ball flower or sand ball galaxy.
Up close you can see the almost perfectly spherical balls that the crabs engineer. They are meticulous in their method, to say the very least.
Just as our own galaxies are separated by space, so it is too with the tiny galaxies that the crabs make - they can extend along the whole reach of the beach.