کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2834122 1164292 2012 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Historical biogeography of the North American glacier ice worm, Mesenchytraeus solifugus (Annelida: Oligochaeta: Enchytraeidae)
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم کشاورزی و بیولوژیک بوم شناسی، تکامل، رفتار و سامانه شناسی
پیش نمایش صفحه اول مقاله
Historical biogeography of the North American glacier ice worm, Mesenchytraeus solifugus (Annelida: Oligochaeta: Enchytraeidae)
چکیده انگلیسی

North American ice worms are the largest glacially-obligate metazoans, inhabiting coastal, temperate glaciers between southcentral Alaska and Oregon. We have collected ice worm specimens from 10 new populations, completing a broad survey throughout their geographic range. Phylogenetic analyses of 87 individuals using fragments of nuclear 18S rRNA, and mitochondrial 12S rRNA and cyctochrome c oxidase subunit 1 (CO1) identified 18 CO1 haplotypes with divergence values up to ∼10%. Phylogeographic interpretations suggest a St. Elias Range, Alaskan ancestry from an aquatic mesenchytraeid oligochaete during the early-Pliocene. A gradual, northward expansion by active dispersal from the central St. Elias clade characterizes a northern clade that is confined to Alaska (with one exception on Vancouver Island, British Columbia), while a distinct southern clade representing worms from British Columbia, Washington and Oregon was likely founded by a passive dispersal event originating from a northern ancestor. The geographic boundary between central and southern clades coincides with an ice worm distribution gap located in southern Alaska, which appears to have restricted active gene flow throughout the species’ evolutionary history.

Figure optionsDownload as PowerPoint slideHighlights
► Northern (N), central (C) and southern (S) ice worm lineages likely separated during the mid-Miocene.
► A distribution gap in southern AK geographically separates the C and S lineages.
► Active gene flow occurs within lineages during glacial maxima.
► Infrequent passive gene flow occurs in a N → S direction.
► Glacial refugia in the St. Elias, Chugach and Cascade ranges has maintained lineages over geological time.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Molecular Phylogenetics and Evolution - Volume 63, Issue 3, June 2012, Pages 577–584
نویسندگان
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