hen they came to it.
So there is a general rule in the herd that each elephant must take just a few of the leaves from a tree, and then move on; and if instead he does block the way, the elephants behind him may push him forward and make him move on.
"But," you may ask, "why can't the other elephants behind him also stop and eat up all the leaves on the trees near them?"
Because then all the trees on that line of march would be bare of leaves, and it might take a whole month for fresh leaves to grow there again. But if the herd took only a portion of the leaves from each tree, there would be enough food for them along that path if they happened to visit it again in a few days.
In fact, the elephants need make only a few such paths through the jungle, if they eat only part of the leaves at a time along any of the paths. Then they can visit these paths in turn on other days, and always find enough food there--because the fresh leaves constantly growing on the trees would mak