Mouse signpost behavior

Piles of leaves, twigs and even shells have been associated with wood mice before, but it was assumed they were used to hide nest-holes. The first hint of their function as sign posts came when one group of mice escaped from their laboratory box. Stopka says, “one dug a hole through the side, and the last one out marked it with a leaf.” In an experiment with discs, the mice appeared to play with the discs, moving them around. But a statistical analysis of their movements, based on continuous videos of their behavior, revealed a strong link between their movements and the position of the discs. They seemed to be using the discs as markers to orient themselves in the otherwise featureless box.