In Vitro Production of the Pheromone Intermediates Ipsdienone and Ipsenone by the Bark Beetles Ips pini (Say) and I. paraconfusus Lanier (Coleoptera: Scolytidae)

Abstract

bees. The capacity of the follower bees to form averages of the distances and directions indicated in the individual wagging runs is not well understood. In this connection it is important whether the total scatter in the pooled data is caused by different bees indicating different average directions, or whether a similar amount of scatter is present in the consecutive wagging runs of a single dance. The latter appears to be true. In Fig. 3, an example is given of the directions indicated by 11 consecutive wagging runs in a single dance announcing food 1 m from the hive. This is the message received by the follower bees that stay with a single dancer for some time. In conclusion, an observation of the directions of individual wagging runs in a reasonable number of dances does not result in any significant directional indication at the distances below 15 m, where typical round dances occur in Apis mellifera carnica. Fairly similar data have been obtained in the Italian race (Apis mellifera ligustica), which has sickleshaped transition dances rather than the direct transition dances used by carnica. Our results thus support the interpretations offered by von Frisch (1967). The significant indication of direction already at a distance of 1 m reported by Kirchner et al. (1988) was obtained by a two-step averaging of at least 60 dances. We do not believe this to be a likely strategy for follower bees, but we are aware that only little is known about the number of round dances actually followed and about the capacity of bees to make averages. Studies on such behavioral aspects are in progress. The Center for Sound Communication is financed by the Danish National Research Foundation.