Sex ratios in Adalia bipunctata populations and population-genetic significance of male killing.

摘要

Secondary sex ratios in individual families and populations of Adalia bipunctata from different European localities were determined. When data on families that produced bisexual (both male and female) progeny were combined, the total progeny numberwas 533 females and 542 males (the proportion of males was 50.4%). In a Moscow population, three out of 52 females produced exclusively female offspring (families without males). European populations exhibited female predominance in the sex ratio in thedirection from south to north. The lowest proportion of males (18.0%) was observed in the population of Stockholm. The biological significance for the population of the presence of females producing unisexual female progeny is discussed.