Evolution and systematics of Cerion (Mollusca, Pulmonata) on New Providence Island : a radical revision. Bulletin of the AMNH ; v. 182, article 4

Simple item page
dc.contributor.authorGould, Stephen Jay.en_US
dc.contributor.authorWoodruff, David S.en_US
dc.date.accessioned2005-10-06T14:22:16Z
dc.date.available2005-10-06T14:22:16Z
dc.date.issued1986en_US
dc.descriptionp. 390-490 : ill., maps ; 26 cm.en_US
dc.descriptionIncludes bibliographical references (p. 488-490).en_US
dc.description.abstract"Cerion has been described by its leading student W.J. Clench as 'the most difficult genus of pulmonate mollusks to classify.' No other pulmonate genus shows greater diversity of form; moreover, almost all these divergent morphologies hybridize at their areas of geographic contact. The result is a taxonomic morass that has effectively debarred fruitful biological work on these fascinating snails. The taxonomy of New Providence Island is the most elaborate for the entire genus; more than 90 species of Cerion have been designated, and the distribution of existing names makes no geographic or ecological sense. We use morphometric and genetic techniques to conclude that the living Cerion of New Providence reduce to two semispecies, C. glans (the ribby morphotype) and C gubernatorium (the mottled morphotype). Traces of an extinct C. agassizi line (a prominent taxon of fossil dunes) survive as introgressions into C. gubernatorium populations of southeastern New Providence. These two groups form the basis of Cerion faunas throughout the northern Bahamas; their separation and recognition provide a key to resolving Cerion's taxonomy both here and elsewhere. Ribby and mottled morphotypes are recurrently evolved 'developmental packages,' not homologous taxa from place to place -- thereby illustrating the importance of developmental channeling in parallel evolution. We base our taxonomic decision upon a conciliance among many independent criteria. Geographic distribution: parental morphotypes occupy their expected positions, with narrow hybrid zones at predicted points of transition. Morphology of parental populations: differences between ribby and mottled are not simple consequences of one minor alteration in growth, but summed results of several independent covariance sets. Morphotypes differ consistently in amounts of variation and patterns of covariance. Hybrid populations: we find both enhanced variation and patterns of covariance based on developmental disturbance never before detected in parental populations of Cerion. Genetics: samples grouped by frequencies of electromorphs yield the same clusters of ribby and mottled populations specified by morphology. Morphotypes can be distinguished by allele frequencies, while hybrid populations contain rare alleles found in neither parental taxon. The genetic hybrid zone is wider than the morphological zone and asymmetric about it. An appendix allocates all previously named taxa, and resolves the status of 19 designated fossil taxa, plus a new species (Cerion clenchi), into three successive faunas, marking waves of migration correlated with rise and fall of Pleistocene seas"--P. 391.en_US
dc.format.extent23215248 bytes
dc.format.mimetypeapplication/pdf
dc.identifier.urihttp://hdl.handle.net/2246/579
dc.languageengen_US
dc.language.isoen_US
dc.publisher[New York] : American Museum of Natural Historyen_US
dc.relation.ispartofseriesBulletin of the American Museum of Natural History ; v. 182, article 4en_US
dc.subject.lccQH1 .A4 vol.182, art.4, 1986en_US
dc.subject.lcshCerion -- Bahamas -- New Providence Islanden_US
dc.subject.lcshCerion -- Evolution.en_US
dc.subject.lcshCerionen_US
dc.subject.lcshMollusks -- Bahamas -- New Providence Islanden_US
dc.subject.lcshMollusks, Fossil -- Bahamas -- New Providence Island.en_US
dc.subject.lcshPaleontology -- Quaternary -- Bahamas -- New Providence Island.en_US
dc.subject.lcshPaleontology -- Bahamas -- New Providence Island.en_US
dc.titleEvolution and systematics of Cerion (Mollusca, Pulmonata) on New Providence Island : a radical revision. Bulletin of the AMNH ; v. 182, article 4en_US
dc.title.alternativeNew Providence Cerionen_US
dc.typetexten_US

Files

Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
/v2/dspace/ingest/pdfSource/bul/B182a04.pdf
Size:
22.14 MB
Format:
Adobe Portable Document Format
Description:
Download

Collections

Bulletin of the American Museum of Natural History