title: Molecular phylogeny of early vertebrates: monophyly of the agnathans as revealed by sequences of 35 genes.
abstract: Extant vertebrates are divided into three major groups: hagfishes (Hyperotreti, myxinoids), lampreys (Hyperoartia, petromyzontids), and jawed vertebrates (Gnathostomata). The phylogenetic relationships among the groups and within the jawed vertebrates are controversial, for both morphological and molecular studies have rendered themselves to conflicting interpretations. Here, we use the sequences of 35 nuclear protein-encoding genes to provide definitive evidence for the monophyly of the Agnatha (jawless vertebrates, a group encompassing the hagfishes and lampreys). Our analyses also give a strong support for the separation of Chondrichthyes (cartilaginous fishes) before the divergence of Osteichthyes (bony fishes) from the other gnathostomes.
authors.affiliation: Max-Planck-Institut für Biologie, Abteilung Immungenetik, Tübingen, Germany. naoko.takezaki@tuebingen.mpg.de
authors.forename: Naoko
authors.initials: N
authors.lastname: Takezaki
authors.forename: Felipe
authors.initials: F
authors.lastname: Figueroa
authors.forename: Zofia
authors.initials: Z
authors.lastname: Zaleska-Rutczynska
authors.forename: Jan
authors.initials: J
authors.lastname: Klein
mesh_terms: D000818:Animals; D019143:Evolution, Molecular; D006196:Hagfishes / Q000235:genetics*; D007798:Lampreys / Q000235:genetics*; D015233:Models, Statistical; D010802:Phylogeny; D013045:Species Specificity; D014714:Vertebrates / Q000235:genetics*