Introgression and Hybridisation in Natural Populations

Abstract

Many of the characteristics of honeybees display the well known phenomenon that multifactorial inheritance essentially converts discontinuous variation of the genotype into continuous variation in the phenotype. Also, the presence of modifying genes holds great significance for populations because they may readily respond to selective pressures and thus provide a population with the flexibility needed to respond to changes in the environment (Wright 1978; Falconer 1989). Because a population is a breeding group in the genetic sense, the genetic constitution of a population is an array of gene frequencies. And, in turn, the gene frequencies of a population of honeybees may well change between generations, with population size, differences in fertility and viability of progeny, migration and mating systems. All of these properties may be affected by selection, which alters the gene frequency in a population (Wright 1978; Falconer 1989).