HOW DO DUNG BEETLES FIND THEIR WAY? -unraveling the navigational system of a beetle with a home

JOCHEN SMOLKA; BASIL EL JUNDI; MARIE DACKE; MARÍA BELÉN MALDONADO; FLORENCIA FERNANDEZ CAMPÓN

Montevideo

Congreso; Reunión Biología del Comportamiento del Cono Sur; 2020

The homing dung beetle Anomiopsoides fedemariai (Scarabaeidae: Scarabaeinae: Eucraniini) is abundant in the arid and semi-arid areas of the Monte Desert of Argentina. We found that while A. fedemariai can forage in any random direction from its nest, it always returns with its pellet of dung taking the shortest path possible, suggesting a path-integrating system. This requires the beetle to sum the vectors of distance and direction travelled from its nest to its current position. For this, the beetles need to make use of a compass and an odometer. In the present study, we investigate the mechanisms involved in the navigational system of this South American homing dung beetle. In this study, we present the compass cues that support the angular orientation of these beetles, as well as the visual system that supports it. In summary, A. fedemariai is able to use the position of the sun and the celestial pattern of polarized light as compass cues for their navigation across the Monte Desert. We further demonstrate that when not able to find its nest, the beetle starts to walk in loops centred around the alleged nest location. This serves as a back-up to their path-integrating system.