Results of χ²-tests for nonsynonymous and synonymous substitutions in <i>SWS1</i>.

χ2-tests compared the observed versus expected numbers of nonsynonymous and synonymous substitutions for SWS1 based on a neutral model of evolution (ω = 1). All three different branch categories are expected to exhibit neutral ω values according to the “coastal” hypothesis of SWS1 evolution. CF = codon frequency model; N = nonsynonymous; S = synonymous; ω = dN/dS; * = significant p values.