It may be a stupid idea.
It was a plank or street sign. The sign was simple, it pointing towards nearby village. The sign can be made using straight branches and a plank. The plank first need to be saw until it looks like an arrow.
The purpose is:
It point out where the village located. First, the eve/villager in already developed village make the sign and put in in every direction. Later, if the village becomes abandoned and eve spawned 200 tiles away from the village, she can follow the sign to the village.