Distribution of clade B serpin ESTs in fish. A dendrogram of fish species is shown with clade B serpins ESTs shown on the right in brackets. The tetrapoda lineage is also indicated, with the simplest locus (Xenopus tropicalis) shown for comparison. Genes are named without the SERPIN root. The relative timing of genome duplication and subsequent gene loss within ray finned fish are shown as well as the composition of the loci after each event. Asterisk indicates an EST for which only the genus name was given.