Evidence for preferential mating in Adalia bipunctata

Abstract

SUMMARYNon-random mating may be involved in the maintenance of colour polymorphism in Adalia bipunctata. Mating choice experiments have been carried out on a stock of A. bipunctata from Keele. Specific frequencies of the melanic quadrimaculata form and the non-melanic typica form were placed in population cages or mating chambers and allowed to mate. The frequencies of the forms amongst mating pairs were scored. The results gave a good fit to a model of mixed sexual selection and assortative mating showing a strongly frequency dependent, non-assorting preference for quadrimaculata males in the matings.Data from the wild Keele population showed a similar preference for quadrimaculata males, and an excess of males of a second melanic phenotype, sexpustulata. Observation of courting pairs indicated that female choice determined frequency of mating. Field data from Keele also gave evidence of assortative mating between typica and another non-melanic form, annulata.

Non-random mating in Adalia bipunctata (the two-spot ladybird). III. New evidence of genetic preference

“…Keele was the first British population in which sexual selection for melanics was demonstrated (Majerus et al, 1982a). Samples from the Keele population were then used for our first experiments to select for preference (Majerus et al, 1 982b) and to set up MOKFs original isofemale lines.…”

Sexual selection and the evolution of preferential mating in ladybirds I. Selection for high and low lines of female preference

“…This was a selection experiment. Majerus, O'Donald and Weir (1982a) showed that both in natural populations in the field and in experimental populations in the laboratory, the melanic quadrimaculata males of the Two-spot Ladybird, Adalia bipunctata have a mating advantage that fits a simple model of preferential mating. If this is produced by a genetically determined female preference, it should be possible to select for increased preferential mating in the population.…”

Non-random mating in the two-spot ladybird (Adalia bipunctata): I. A reassessment of the evidence

“…Mader, 1926-37;Lus, 1928;1932). Often, they are grouped together for convenience as the form annulata (Creed, 1966;Majerus et a!., 1982a). Lus (1928Lus ( , 1932 was the first to work on the genetics of this polymorphism, which he explained in terms of multiple alleles at a single locus.…”