title: Biophysical and Population Genetic Models Predict the Presence of "Phantom" Stepping Stones Connecting Mid-Atlantic Ridge Vent Ecosystems.
abstract: Deep-sea hydrothermal vents are patchily distributed ecosystems inhabited by specialized animal populations that are textbook meta-populations. Many vent-associated species have free-swimming, dispersive larvae that can establish connections between remote populations. However, connectivity patterns among hydrothermal vents are still poorly understood because the deep sea is undersampled, the molecular tools used to date are of limited resolution, and larval dispersal is difficult to measure directly. A better knowledge of connectivity is urgently needed to develop sound environmental management plans for deep-sea mining. Here, we investigated larval dispersal and contemporary connectivity of ecologically important vent mussels (Bathymodiolus spp.) from the Mid-Atlantic Ridge by using high-resolution ocean modeling and population genetic methods. Even when assuming a long pelagic larval duration, our physical model of larval drift suggested that arrival at localities more than 150 km from the source site is unlikely and that dispersal between populations requires intermediate habitats ("phantom" stepping stones). Dispersal patterns showed strong spatiotemporal variability, making predictions of population connectivity challenging. The assumption that mussel populations are only connected via additional stepping stones was supported by contemporary migration rates based on neutral genetic markers. Analyses of population structure confirmed the presence of two southern and two hybridizing northern mussel lineages that exhibited a substantial, though incomplete, genetic differentiation. Our study provides insights into how vent animals can disperse between widely separated vent habitats and shows that recolonization of perturbed vent sites will be subject to chance events, unless connectivity is explicitly considered in the selection of conservation areas.
authors.affiliation: GEOMAR Helmholtz Centre for Ocean Research, 24105 Kiel, Germany. Electronic address: cbreusing@geomar.de.
authors.forename: Corinna
authors.initials: C
authors.lastname: Breusing
authors.affiliation: GEOMAR Helmholtz Centre for Ocean Research, 24105 Kiel, Germany.
authors.forename: Arne
authors.initials: A
authors.lastname: Biastoch
authors.affiliation: GEOMAR Helmholtz Centre for Ocean Research, 24105 Kiel, Germany.
authors.forename: Annika
authors.initials: A
authors.lastname: Drews
authors.affiliation: Department of Oceanography, Dalhousie University, Halifax, NS B3H 4R2, Canada.
authors.forename: Anna
authors.initials: A
authors.lastname: Metaxas
authors.affiliation: CNRS, Sorbonne Universités, UMR 7144 CNRS-UPMC, Adaptation et Diversité en Milieu Marin, Équipe ABICE, Station Biologique de Roscoff, 29688 Roscoff Cedex, France.
authors.forename: Didier
authors.initials: D
authors.lastname: Jollivet
authors.affiliation: Monterey Bay Aquarium Research Institute, Moss Landing, CA 95039, USA.
authors.forename: Robert C
authors.initials: RC
authors.lastname: Vrijenhoek
authors.affiliation: GEOMAR Helmholtz Centre for Ocean Research, 24105 Kiel, Germany.
authors.forename: Till
authors.initials: T
authors.lastname: Bayer
authors.affiliation: GEOMAR Helmholtz Centre for Ocean Research, 24105 Kiel, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Melzner
authors.affiliation: Symbiosis Department, Max Planck Institute for Marine Microbiology, 28359 Bremen, Germany.
authors.forename: Lizbeth
authors.initials: L
authors.lastname: Sayavedra
authors.affiliation: Symbiosis Department, Max Planck Institute for Marine Microbiology, 28359 Bremen, Germany; Department of Microbiology and Ecosystem Science, University of Vienna, 1090 Vienna, Austria.
authors.forename: Jillian M
authors.initials: JM
authors.lastname: Petersen
authors.affiliation: Symbiosis Department, Max Planck Institute for Marine Microbiology, 28359 Bremen, Germany.
authors.forename: Nicole
authors.initials: N
authors.lastname: Dubilier
authors.affiliation: Institute of Clinical Molecular Biology (IKMB), Christian-Albrechts-Universität zu Kiel, 24105 Kiel, Germany.
authors.forename: Markus B
authors.initials: MB
authors.lastname: Schilhabel
authors.affiliation: Institute of Clinical Molecular Biology (IKMB), Christian-Albrechts-Universität zu Kiel, 24105 Kiel, Germany.
authors.forename: Philip
authors.initials: P
authors.lastname: Rosenstiel
authors.affiliation: GEOMAR Helmholtz Centre for Ocean Research, 24105 Kiel, Germany.
authors.forename: Thorsten B H
authors.initials: TB
authors.lastname: Reusch
mesh_terms: D063147:Animal Distribution; D000818:Animals; D001267:Atlantic Ocean; D017753:Ecosystem; D014644:Genetic Variation; D060086:Hydrothermal Vents; D007814:Larva / Q000235:genetics / Q000254:growth & development; D008957:Models, Genetic; D008962:Models, Theoretical; D049879:Mytilidae / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D017422:Sequence Analysis, DNA