ESTIMATION OF THE RATE OF INBREEDING IN A NATURAL-POPULATION OF ADALIA-BIPUNCTATA (COLEOPTERA, COCCINELLIDAE) USING A PHENOTYPIC INDICATOR

The rate of inbreeding is an important parameter in the population and evolutionary genetics of a species. Accurate measurement of the rate of close inbreeding can be gained through the use of DNA fingerprintin g; however, this is both labour intensive and expensive. We here provi de a more approximate measure of the rate of close inbreeding in Adali a bipunctata, utilising the unusual phenotypic effect of inbreeding, t he production of eggs which develop but fail to hatch, which is seen i n this species. Examination of the incidence of grey eggs in known out bred and inbred laboratory crosses and comparison to their incidence i n wild-collected clutches produced an upper estimate of 2.7% of wild c lutches being the product of close inbreeding. This result is discusse d in the light of the ecology and evolutionary biology of Adalia bipun ctata.