Remote sensing of the atmosphere by VHF radar experiments

Problems in atmospheric dynamics, in particular in micro- and mesoscale processes, which can be solved by radar investigations, are summarized. The method of atmospheric radar experiments is described. Some relevant results obtained with the new SOUSY-VHF-Radar are presented, including observations of a warm-front passage, of layered structures, and of vertical and horizontal velocities in the troposphere. A power profile of radar echoes from heights up to the stratosphere proves that the SOUSY-VHF-Radar in its final operating state will be able to investigate structures and dynamics in the mesosphere too.     

Virgin ant queens mate with their own sons to avoid failure at colony foundation

Mother–son mating (oedipal mating) is practically non-existent in social Hymenoptera, as queens typically avoid inbreeding, mate only early in life and do not mate again after having begun to lay eggs. In the ant genus Cardiocondyla mating occurs among sib in the natal nests. Sex ratios are extremely female-biased and young queens face the risk of remaining without mating partners. Here, we show that virgin queens of Cardiocondyla argyrotricha produce sons from their own unfertilized eggs and later mate with them to produce female offspring from fertilized eggs. Oedipal mating may allow C. argyrotricha queens to found new colonies when no mating partners are available and thus maintains their unusual life history combining monogyny, mating in the nest, and low male production. Our result indicates that a trait that sporadically occurs in solitary haplodiploid animals may evolve also in social Hymenoptera under appropriate ecological and social conditions.