Phylogenetic tree of the TMEM18 family. The phylogenetic tree was calculated from a nucleotide multiple sequence alignment with a maximum-likelihood approach using the RAxML program. The tree was bootstrapped 1000 times and branch lengths correspond to log-likelihood scores (see scale). The sequence similarities and identities (percentage of alignment length) for each protein are towards the human TMEM18 protein and were calculated from global alignments produced with the EMBOSS implementation of the Needleman-Wunsch algorithm. The time points since the divergence of animals and plants/T. pseudonana (1625 MYA) and since the radiation of vertebrates (797 MYA) were taken from the TimeTree resource.