 It has also been suggested, most notably by John Gillespie (2000a,b, 2001), that many purported instances of genetic drift are in fact due to “genetic draft.” Genetic draft is a process of linked selection (a hitchhiking process) where it is a matter of chance which of two neutral alleles (in a two-locus model) happens to be linked to a site that undergoes an advantageous mutation, and where the timing of these mutations, followed by a rapid selective “sweep” to fixation, is random. As Skipper (2006) discusses, one of the interesting properties of genetic draft is that it can produce an outcome similar to that which one would expect from genetic drift in small populations, namely, a reduction in genetic variation (thus the similar name). Gillespie argues that draft is less sensitive to population size than drift, which leads him to claim that draft is a more significant cause of evolution than drift (Skipper 2006). Thus, draft introduces yet another relative significance debate (Beatty 1995, 1997) to add to the others discussed in this article: drift vs. selection, Wright’s SBT vs. Fisher’s mass selection, neutralist vs. nearly neutralist vs. selectionist molecular evolution. However, it is worth noting that while draft can produce one of the same outcomes that drift can (reduction in heterozygosity), it would not give rise to fluctuating gene frequencies from one generation to the next. So, not all drifty outcomes can be accounted for by draft.