Fig. 4

Phylogenetic reconstructions showing diversification and lineage-specific expansions of Eph-receptors and ligand ephrins. Phylogenetic tree topologies were inferred using Maximum Likelihood approach as implemented in RAxML and IQ-TREE softwares, and Bayesian approach as implemented in MrBayes software. Bootstrap values of > 50% as estimated using RAxML (Black) and IQ-Tree (Red) are marked on the key nodes and corresponding Bayesian posterior probability of threshold > 90% are shown as black dots. a Evolutionary relationships of metazoan Eph receptors, highlighting multiple expansions in cnidarians and sponges. The tree topology is inferred using the canonical intracellular Pkinase-Tyr domain. The Pkinase-Tyr domains of closely related non-metazoans RTKs were used as outgroup. b Evolutionary relationships of metazoan Eph receptors, highlighting multiple expansions in cnidarians and sponges. The tree topology is inferred using the extracellular ligand binding domain. N-terminal regions of closely related non-metazoan RTKs were used as outgroup. c Evolutionary relationships among metazoan ephrin ligands, highlighting multiple expansions in cnidarians. Closely related monodomain cupredoxins were used as outgroup. See Additional file 1, Figure S4, S5 and S6 for complete sequence labels and support values for the topologies shown in panels a, b and c, respectively. Raw tree files are provided in Additional file 3