Don't know why, but the little beggars *always* line up in single file whenever the group is moving. I'd like to paint a number on each one and see if there's a fixed "pecking order". These guys cross the road to lunch in our grass several times a day. When we see them, we scramble outside to serve as traffic wardens when they decide to go back -- even though they obviously got across to our side without getting smooshed. We've tried hurrying them along, but the parents just turn on us and hiss like an annoyed rattler -- or the male starts charging us. If it weren't so cute and fun, it would be a pain in the butt.