“…In previous contexts, such a model has been used to model quantitative trait evolution, called a continuum-of-alleles model [Kimura, 1965]. Earlier approaches to incorporate genetic drift into a continuum-of-alleles model using the theory of measure-valued diffusions [Fleming and Viot, 1979, Ethier and Kurtz, 1987] have made significant advances in understanding the neutral dynamics of such processes [Dawson and Hochberg, 1982, Ethier and Griffiths, 1993, Ethier and Kurtz, 1993, Donnelly and Kurtz, 1996]. However, incorporating selection greatly increases the difficulty of obtaining analytical results (but see Donnelly and Kurtz [1999], Dawson and Feng [2001]).…”