title: Evidence from 18S ribosomal DNA that the lophophorates are protostome animals.
abstract: The suspension-feeding metazoan subkingdom Lophophorata exhibits characteristics of both deuterostomes and protostomes. Because the morphology and embryology of lophophorates are phylogenetically ambiguous, their origin is a major unsolved problem of metazoan phylogenetics. The complete 18S ribosomal DNA sequences of all three lophophorate phyla were obtained and analyzed to clarify the phylogenetic relationships of this subkingdom. Sequence analyses show that lophophorates are protostomes closely related to mollusks and annelids. This conclusion deviates from the commonly held view of deuterostome affinity.
authors.affiliation: Department of Zoology, University of Texas, Austin 78712.
authors.forename: K M
authors.initials: KM
authors.lastname: Halanych
authors.forename: J D
authors.initials: JD
authors.lastname: Bacheller
authors.forename: A M
authors.initials: AM
authors.lastname: Aguinaldo
authors.forename: S M
authors.initials: SM
authors.lastname: Liva
authors.forename: D M
authors.initials: DM
authors.lastname: Hillis
authors.forename: J A
authors.initials: JA
authors.lastname: Lake
mesh_terms: D000818:Animals; D005075:Biological Evolution; D002013:Bryozoa / Q000145:classification* / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry*; D007448:Invertebrates / Q000145:classification* / Q000235:genetics; D008969:Molecular Sequence Data; D010802:Phylogeny; D012337:RNA, Ribosomal, 18S / Q000235:genetics*; D017422:Sequence Analysis, DNA; D009626:Terminology as Topic
chemical_list: D004275:DNA, Ribosomal; D012337:RNA, Ribosomal, 18S