Additional file 4: of The chordate ancestor possessed a single copy of the Brachyury gene for notochord acquisition

Molecular phylogeny of Brachyury family members based on an amino acid dataset comprising 436 unambiguously aligned sites. Arrowheads indicate topological incongruities with the tree obtained from comparisons of nucleotides (Fig. 2). Probably due to the short length of the analyzed sequence, the Botryllus schlosseri (urochordate) gene was placed as a sister lineage of a clade comprising cephalochordate and vertebrate genes. (PDF 150 kb)