Relationships between the milk protein sequences of mammalian taxa. This milk protein consensus tree, which is incongruous with the accepted phylogeny shown in Figure 1, was derived from a super-alignment of milk protein amino acid sequences for those genes with single copy orthologs in all seven species. The numbers indicate the percent of bootstraps that support the internal branch and the length of the scale bar represents the number of amino acid substitutions per unit site.
Lemay et al. Genome Biology 2009 10:R43 doi:10.1186/gb-2009-10-4-r43