The Breeding Group and Seed Storage: A Study in Population Dynamics

This is a report on the yearly frequencies since 1941 of blue and white flowered plants of Linanthus parryae, a conspicuous annual of the Mojave desert. Like most desert annuals, its abundance and dispersion varies greatly from year to year and from place to place in response to weather. The size of the breeding group would be expected to vary with
these expansions and contractions. An initial survey (Epling and Dobzhansky, 1942) suggested that the inheritance of color depends on one pair of alleles. Having these natural markers, the species appeared to be a useful subject with which to study the effects of selection and genetic drift.