III. Ökotoxikologische Charakterisierung der Schwermetall-Immissionsmuster

The spatial variation of the immission patterns of Cr, Fe, Pb and V in the region Leipzig-Halle is dicussed in terms of similarities as well as dissimilarities. The representation by isopleths enables the identification of areas with high and low air pollution. The immission patterns can be used as criteria to select areas suitable for in-field testing so that possible effects on fauna und flora and xenobiotic fluxes can be studied at representative sites. The comparison with literature data yields a first characterization of the ecotoxic potential of the heavy-metal immission for the region. By the principal component analysis a comparative evaluation of the spatial structure of all element contents is performed, which leads to conclusions about emission sources and the physicochemical behaviour of the elements.     

Sex linkage among genes controlling sexually selected traits

Using literature data on reciprocal crosses I estimated the influence of sex-chromosomal genes on morphological and behavioral traits. To determine a special role of the sex chromosomes for sexually selected traits, I compared the estimated influence of X-chromosomal genes on sexually selected traits with their estimated influence on traits not under sexual selection. About one-third of the phenotypic variation in sexually selected traits is caused by X-chromosomal genes. There was, in contrast, no significant influence of X-chromosomal genes on traits that were classified as not sexually selected. Sexually selected traits thus seem to be influenced significantly more by X-chromosomal genes than traits not under sexual selection. Though this differential influence of X-chromosomal genes cannot readily be explained with current theoretical knowledge, it may shed some light on X-linked hybrid sterility and on the discussion between arbitrary and good-gene models for the evolution of female choice. Received: 30 January 1998 / Accepted after revision: 20 June 1998