Inheritance of solar direction finding in sandhoppers

Summary Three natural populations ofTalitrus saltator living on differently orientated seashores and the offspring produced by crossing two of them were analysed by means of progeny tests, with the aim of gaining some data on the genetic control of solar direction finding. Data from fullsib family-analyses showed a genetic heterogeneity within at least two of the populations tested: some families oriented towards the sea, some in a different direction and others were dispersed. Intrafamily behaviour in the first and second generations and a mass analysis of dispersed families, suggests that dispersion may arise from segregation of heterozygous parental genotypes. The data obtained generally support the hypothesis of an oligogenic rather than a polygenic control of direction finding.Abbreviations TED theorical escape direction - IED innate escape direction