 With a larger data set covering several more years, Ford (1975: 146) revisited this exchange and argued that Wright remained wrong on each count. Ford also showed that the selective advantage for the rarer of the genes varied widely, from −0.10 to +0.20, and that there was no evidence of heterozygote advantage. He did not find, however, the expected negative correlation between strength of selection and population size in these data. In the intervening decades, data from a variety of other organisms and natural population had become available and its review led Ford to conclude: 