A new computational model for the homebound journey of some geotrupid beetles

After their tortuous foraging excursions some geotrupid beetles are able to return home by walking backwards in a straight line. Thanks to their navigational performances they reach the neighbourhood of their hole; then they rely on olfactory cues to locate it. As with other animals, both invertebrates and vertebrates, these insects can use self-generated and updated information about their position in relation to their hole. that could be possible thanks to a sort of accumulator that keeps a running tally of the current direction and distance from home. In such a way they could estiimate both the direction toward the goal (home) and the distance to travel to reach it. Here we propose to plain algorithms, based on the estimated co-ordinates of foraging site, which could enable the animal to return home. This new computational model seems to quite well fit the homing data of the geotrupids investigated.