Genetics of oviposition-site preference in Drosophila tripunctata.

A survey of 175 isofemale strains from seven populations of Drosophila tripunctata showed that the preferences of females for mushrooms versus tomatoes as oviposition sites follow an approximately normal distribution among strains, as would be expected if this behaviour were governed by many genes with small, additive effects. However, crosses among several strains revealed the existence of autosomal genes with dominance and interaction effects having substantial influence on oviposition-site preference. Despite the apparent genetic complexity of this behaviour, it was found that at least one locus affecting this preference is linked to the autosomal gene encoding the enzyme aconitase, thus encouraging the belief that it may eventually be possible to study the molecular and developmental basis for this evolutionarily important behaviour.