Towards a phylogeny of chitons (Mollusca, Polyplacophora) based on combined analysis of five molecular loci

Okusu, Akiko; Schwabe, Enrico; Eernisse, Douglas J.; Giribet, Gonzalo

doi:10.1078/1439-6092-00085

Cited by 94 publications

(89 citation statements)

References 47 publications

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“…'91; also Jablonski, '93) essentially adopted the taxonomy used by Sepkoski ('82) in his compendium of marine animal families, which in turn was derived mainly from the monumental Treatise on Invertebrate Paleontology. The new analyses discussed here are based on the more cladistic, phylogenetically based classification of Benton ('93), with substantial updates (e.g., Smith, 2001;Hooper and Van Soest, 2002;Mikkelsen, 2002;Williams et al, 2002;Daly et al, 2003;Okusu et al, 2003;Grande et al, 2004). The revised classifications increase the number of orders analyzed from 42 to 53.…”

Section: Analyzing Environmental Histories Of Major Groupsmentioning

confidence: 96%

Evolutionary innovations in the fossil record: the intersection of ecology, development, and macroevolution

Jablonski

2005

J Exp Zool Pt B

100

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The origins of evolutionary innovations have been intensively studied, but relatively little is known about their large-scale ecological patterns. For post-Paleozoic benthic marine invertebrates, which have the richest and most densely sampled fossil record, order-level taxa tend to appear first in onshore, disturbed habitats, even in groups that are now exclusively deep-water (so that present-day distributions are not reliable indicators of original environments). New results presented here show that the onshore-origination pattern is robust to shifts in taxonomic methods and to new paleontological discoveries, and the few available studies suggest that this pattern can also be seen in terms of excursions in morphospace or the acquisition of derived character states, without reference to taxonomic categories. The environmental pattern at high levels contrasts significantly with the origin of low-level novelties (such as defined genera and families) in crinoids, echinoids, and bryozoans, where first appearances tend to conform to their clade-specific bathymetric diversity gradients. This discordance seems to eliminate potential driving mechanisms that simply scale up within-population genetic or ecological processes. Little is known about the factors that promote the onshore-offshore expansion of orders across the continental shelf, or that drive some clades to abandon ancestral habitats for an exclusively deep-water distribution. The origin of evolutionary innovation must ultimately reside in developmental changes, but the onshore-origination bias could emerge from two different dynamics: the pattern could be primarily genetic and developmental, i.e., innovations truly arise onshore; or primarily ecological, i.e., innovations arise randomly but preferentially survive onshore. Whatever the ultimate driving mechanisms, these macroevolutionary patterns show that theories of large-scale evolutionary novelty must include an ecological dimension.

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Section: Analyzing Environmental Histories Of Major Groupsmentioning

confidence: 96%

Evolutionary innovations in the fossil record: the intersection of ecology, development, and macroevolution

Jablonski

2005

J Exp Zool Pt B

100

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“…Polyplacophora (Okusu et al 2003), suggesting that it may not be the most appropriate chiton outgroup, a parsimony tree of ingroup plus representative chiton SSU sequences showed that the patristic distance from it to the ingroup node remained among the shortest. Acanthopleura was therefore retained as a representative chiton, and the required portion of the LSU gene sequence was obtained from a congeneric species, A. granulatum.…”

Section: Taxon Selection and Rooting Proceduresmentioning

confidence: 99%

“…For one phoronid, a craniid, a polychaete, a nemertine and a sponge, SSU and LSU sequences from separate individuals or taxa were concatenated to form chimaeras, either because sequences from the same outgroup species were not available in GenBank or because both sequences could not be obtained readily from the same individual DNA; these entries occur in different lines of the Table and are marked with asterisks (*). The following additional sequences were used in preliminary analyses only: brachiopod Glottidia palmeri Baja California, AF201744 (Cohen 2000); phoronid Phoronopsis viridis, AF123308 (G. Giribet, unpublished); chitons Katharina tunicata, AY377650, and Lepidochiton asellus, AY377631 (Okusu et al 2003); bivalve molluscs Arca noae, X90960, Atrina pectinata, X90961 (Steiner and Muller 1996), and Chlamys islandica, L11232 (Kenchington et al 1993); gastropod molluscs Onchidella celtica, X70211 (Winnepenninckx et al 1994), Limicolaria kambeul, X66374 (Winnepenninckx et al 1992); polychaete Nereis virens Z83754 (Kim et al 1996); nemertine Lineus sp.…”

Section: Sequences Data-editing and Alignmentmentioning

confidence: 99%

Molecular evidence that phoronids are a subtaxon of brachiopods (Brachiopoda: Phoronata) and that genetic divergence of metazoan phyla began long before the early Cambrian

Cohen

Weydmann

2005

Organisms Diversity & Evolution

136

113

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Concatenated SSU (18S) and partial LSU (28S) sequences ($2 kb) from 12 ingroup taxa, comprising 2 phoronids, 2 members of each of the craniid, discinid, and lingulid inarticulate brachiopod lineages, and 4 rhynchonellate, articulate brachiopods (2 rhynchonellides, 1 terebratulide and 1 terebratellide) were aligned with homologous sequences from 6 protostome, deuterostome and sponge outgroups (3964 sites). Regions of potentially ambiguous alignment were removed, and the resulting data (3275 sites, of which 377 were parsimony-informative and 635 variable) were analysed by parsimony, and by maximum and Bayesian likelihood using objectively selected models. There was no base composition heterogeneity. Relative rate tests led to the exclusion (from most analyses) of the more distant outgroups, with retention of the closer pectinid and polyplacophoran (chiton). Parsimony and likelihood bootstrap and Bayesian clade support values were generally high, but only likelihood analyses recovered all brachiopod indicator clades designated a priori. All analyses confirmed the monophyly of (brachiopods+phoronids) and identified phoronids as the sister-group of the three inarticulate brachiopod lineages. Consequently, a revised Linnean classification is proposed in which the subphylum Linguliformea comprises three classes: Lingulata, 'Phoronata' (the phoronids), and 'Craniata' (the current subphylum Craniiformea). Divergence times of all nodes were estimated by regression from node depths in non-parametrically rate-smoothed and other chronograms, calibrated against palaeontological data, with probable errors not less than 50 My. Only three predicted brachiopod divergence times disagree with palaeontological ages by more than the probable error, and a reasonable explanation exists for at least two. Pruning long-branched ingroups made scant difference to predicted divergence time estimates. The palaeontological age calibration and the existence of Lower Cambrian fossils of both main brachiopod clades together indicate that initial genetic divergence between brachiopod and molluscan (chiton) lineages occurred well before the Lower Cambrian, suggesting that much divergence between metazoan phyla took place in the Proterozoic.

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“…This polyplacophoran species is adapted to cold water and is widely spread in Antarctica. Previous studies have involved Hox [Biscotti et al, 2007b] and ParaHox genes [Barucca et al, 2006], the main phylogenetic markers [Okusu et al, 2003], and the karyotype with 2n = 32 chromosomes .…”

mentioning

confidence: 99%

Novel Repeated DNAs in the Antarctic Polyplacophoran Nuttallochiton mirandus (Thiele, 1906)

Biscotti

Canapa

Capriglione

et al. 2014

Cytogenet Genome Res

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Within the scope of a project on the characterization of satellite DNAs in polar mollusks, the Antarctic chiton Nuttallochitonmirandus (Thiele, 1906) was analyzed. Two novel families of tandemly repeated DNAs, namely NmH and NmP, are described in their structure and chromosomal localization, and, furthermore, their presence was analyzed in related species. Data reported here display a particular variability in the structural organization of DNA satellites within this species. Processes driving satellite evolution, which are likely responsible for the intriguing variability of the identified satellite DNAs, are discussed.

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Towards a phylogeny of chitons (Mollusca, Polyplacophora) based on combined analysis of five molecular loci

Cited by 94 publications

References 47 publications

Evolutionary innovations in the fossil record: the intersection of ecology, development, and macroevolution

Evolutionary innovations in the fossil record: the intersection of ecology, development, and macroevolution

Molecular evidence that phoronids are a subtaxon of brachiopods (Brachiopoda: Phoronata) and that genetic divergence of metazoan phyla began long before the early Cambrian

Novel Repeated DNAs in the Antarctic Polyplacophoran <b><i>Nuttallochiton</i></b> <b><i>mirandus </i></b>(Thiele, 1906)

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