GENETIC POLYMORPHISM AND EVOLUTION IN PARTHENOGENETIC ANIMALS. I. POLYPLOID CURCULIONIDAE

Esko Suomalainen ¹ and Anssi Saura ¹

¹ Department of Genetics, University of Helsinki, P. Rautatiekatu 13, SF 00100 Helsinki 10, Finland

The genetic variability at enzyme loci in different triploid and tetraploid parthenogenetic weevil populations has been elucidated by starch gel electrophoresis. The overall genotype of individual weevils belonging to different populations has been determined for over 25 loci. The results are compared with those obtained for diploid bisexual races of either the same or closely related species. The variation within a parthenogenetic population differs from that in diploid, sexually reproducing populations, i.e. the allele frequencies are not in a Hardy-Weinberg equilibrium. The results indicate that apomictic parthenogenetic populations can differentiate genetically. The genotypes within a population resemble each other more than genotypes belonging to different populations. It is evident that evolution still continues—even if slowed down—in parthenogenetic weevils. A comparison between the allele relationships in geographically isolated polyploid parthenogenetic populations and related diploid bisexual forms does not support the hypothetical hybrid origin of parthenogenesis and polyploidy in weevils. Parthenogenesis within a parthenogenetic weevil species is evidently monophyletic.