Astrotaktisches Heimfindevermögen tragender und getragener Ameisen (Cataglyphis bicolor Fabr., Hymenoptera, Formicidae)

Abstract

Workers of the desert ant Cataglyphis bicolor carry their nestmates in typical formicine fashion. In photographs of 43 ants carrying an adult nestmate the head posture of each carrier and carried had been measured in accordance to the horizontal. No differences are found between the mean angles of carriers 41.1°+0.8°) and carried 41.2+0.7°; p>0.35). In open field experiments performed in an area, where two nests were connected by inter-nest transports over a distance of 20m (fig.2), couples of carriers and carried have been captured after runs of 10 m. In a totally flat test area unknown to the ants the carried separated from their carriers are able to perform correct astromenotactic return runs in the presumed home direction (fig. 4). The carriers, however, head for the presumed nest destination. The same result is obtained after training runs of 10 m performed on a transparent plastic folio which compensates thecarrier's run by rotating at adequate velocities (figs 3 and 5). The carried ant seems to be able to integrate azimuth and length of various run intervals during the training run, without touching the ground or seeing any surroundings passing by. The results are discussed regarding their biological significance.