Watching the Merry-Go-Round

Critters give us the excuse to stop and watch and wonder. We separated the older ewes from the ewe lambs recently. They are in adjoining pastures for now, and the older ewes are in the area with the chicken shed. Because the ewe lambs didn't have much pasture, I gave them hay near the chicken shed, and I noticed the older ewes are playing follow the leader, walking single file around the chicken shed. Do they have a leader? I wonder as they walk circle after circle. What will cause them to stop the game? And what would people think if they saw an adult staring at sheep walking in circles on a frosty Sunday morning?