The recent availability of several fully sequenced plant genomes
has bolstered phylogenetic reconstruction of duplication in the
SPL gene family. Salinas et al. (2012) recently reported eight
(I-VIII) major SPL clades, at least four of which predate the
diversification of embryophytes (land plants) based on a neighborjoining algorithm, whereas Guo et al. (2008) identified six major
clades