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Three-dimensional magnetic stripes require slow cooling in fast-spread lower ocean crust. Nature 2021; 597:511-515. [PMID: 34552253 DOI: 10.1038/s41586-021-03831-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Accepted: 07/16/2021] [Indexed: 11/09/2022]
Abstract
Earth's magnetic field is recorded as oceanic crust cools, generating lineated magnetic anomalies that provide the pattern of polarity reversals for the past 160 million years1. In the lower (gabbroic) crust, polarity interval boundaries are proxies for isotherms that constrain cooling and hence crustal accretion. Seismic observations2-4, geospeedometry5-7 and thermal modelling8-10 of fast-spread crust yield conflicting interpretations of where and how heat is lost near the ridge, a sensitive indicator of processes of melt transport and crystallization within the crust. Here we show that the magnetic structure of magmatically robust fast-spread crust requires that crustal temperatures near the dike-gabbro transition remain at approximately 500 degrees Celsius for 0.1 million years. Near-bottom magnetization solutions over two areas, separated by approximately 8 kilometres, highlight subhorizontal polarity boundaries within 200 metres of the dike-gabbro transition that extend 7-8 kilometres off-axis. Oriented samples with multiple polarity components provide direct confirmation of a corresponding horizontal polarity boundary across an area approximately one kilometre wide, and indicate slow cooling over three polarity intervals. Our results are incompatible with deep hydrothermal cooling within a few kilometres of the axis2,7 and instead suggest a broad, hot axial zone that extends roughly 8 kilometres off-axis in magmatically robust fast-spread ocean crust.
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Ho PT, Park E, Hong SG, Kim EH, Kim K, Jang SJ, Vrijenhoek RC, Won YJ. Geographical structure of endosymbiotic bacteria hosted by Bathymodiolus mussels at eastern Pacific hydrothermal vents. BMC Evol Biol 2017; 17:121. [PMID: 28558648 PMCID: PMC5450337 DOI: 10.1186/s12862-017-0966-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Accepted: 05/12/2017] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Chemolithoautotrophic primary production sustains dense invertebrate communities at deep-sea hydrothermal vents and hydrocarbon seeps. Symbiotic bacteria that oxidize dissolved sulfur, methane, and hydrogen gases nourish bathymodiolin mussels that thrive in these environments worldwide. The mussel symbionts are newly acquired in each generation via infection by free-living forms. This study examined geographical subdivision of the thiotrophic endosymbionts hosted by Bathymodiolus mussels living along the eastern Pacific hydrothermal vents. High-throughput sequencing data of 16S ribosomal RNA encoding gene and fragments of six protein-coding genes of symbionts were examined in the samples collected from nine vent localities at the East Pacific Rise, Galápagos Rift, and Pacific-Antarctic Ridge. RESULTS Both of the parapatric sister-species, B. thermophilus and B. antarcticus, hosted the same numerically dominant phylotype of thiotrophic Gammaproteobacteria. However, sequences from six protein-coding genes revealed highly divergent symbiont lineages living north and south of the Easter Microplate and hosted by these two Bathymodiolus mussel species. High heterogeneity of symbiont haplotypes among host individuals sampled from the same location suggested that stochasticity associated with initial infections was amplified as symbionts proliferated within the host individuals. The mussel species presently contact one another and hybridize along the Easter Microplate, but the northern and southern symbionts appear to be completely isolated. Vicariance associated with orogeny of the Easter Microplate region, 2.5-5.3 million years ago, may have initiated isolation of the symbiont and host populations. Estimates of synonymous substitution rates for the protein-coding bacterial genes examined in this study were 0.77-1.62%/nucleotide/million years. CONCLUSIONS Our present study reports the most comprehensive population genetic analyses of the chemosynthetic endosymbiotic bacteria based on high-throughput genetic data and extensive geographical sampling to date, and demonstrates the role of the geographical features, the Easter Microplate and geographical distance, in the intraspecific divergence of this bacterial species along the mid-ocean ridge axes in the eastern Pacific. Altogether, our results provide insights into extrinsic and intrinsic factors affecting the dispersal and evolution of chemosynthetic symbiotic partners in the hydrothermal vents along the eastern Pacific Ocean.
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Affiliation(s)
- Phuong-Thao Ho
- Interdisciplinary Program of EcoCreative, The Graduate School, Ewha Womans University, Seoul, 03760, Korea
| | - Eunji Park
- Division of EcoScience, Ewha Womans University, Seoul, 03760, Korea
| | - Soon Gyu Hong
- Division of Polar Life Sciences, Korea Polar Research Institute, 26 Songdomirae-ro, Yeonsu-gu, Incheon, 21990, Republic of Korea
| | - Eun-Hye Kim
- Division of Polar Life Sciences, Korea Polar Research Institute, 26 Songdomirae-ro, Yeonsu-gu, Incheon, 21990, Republic of Korea
| | - Kangchon Kim
- Interdisciplinary Program of EcoCreative, The Graduate School, Ewha Womans University, Seoul, 03760, Korea
| | - Sook-Jin Jang
- Interdisciplinary Program of EcoCreative, The Graduate School, Ewha Womans University, Seoul, 03760, Korea
| | | | - Yong-Jin Won
- Interdisciplinary Program of EcoCreative, The Graduate School, Ewha Womans University, Seoul, 03760, Korea. .,Division of EcoScience, Ewha Womans University, Seoul, 03760, Korea.
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Jang SJ, Park E, Lee WK, Johnson SB, Vrijenhoek RC, Won YJ. Population subdivision of hydrothermal vent polychaete Alvinella pompejana across equatorial and Easter Microplate boundaries. BMC Evol Biol 2016; 16:235. [PMID: 27793079 PMCID: PMC5084463 DOI: 10.1186/s12862-016-0807-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Accepted: 10/14/2016] [Indexed: 11/29/2022] Open
Abstract
Background The Equator and Easter Microplate regions of the eastern Pacific Ocean exhibit geomorphological and hydrological features that create barriers to dispersal for a number of animals associated with deep-sea hydrothermal vent habitats. This study examined effects of these boundaries on geographical subdivision of the vent polychaete Alvinella pompejana. DNA sequences from one mitochondrial and eleven nuclear genes were examined in samples collected from ten vent localities that comprise the species’ known range from 23°N latitude on the East Pacific Rise to 38°S latitude on the Pacific Antarctic Ridge. Results Multi-locus genotypes inferred from these sequences clustered the individual worms into three metapopulation segments — the northern East Pacific Rise (NEPR), southern East Pacific Rise (SEPR), and northeastern Pacific Antarctic Ridge (PAR) — separated by the Equator and Easter Microplate boundaries. Genetic diversity estimators were negatively correlated with tectonic spreading rates. Application of the isolation-with-migration (IMa2) model provided information about divergence times and demographic parameters. The PAR and NEPR metapopulation segments were estimated to have split roughly 4.20 million years ago (Mya) (2.42–33.42 Mya, 95 % highest posterior density, (HPD)), followed by splitting of the SEPR and NEPR segments about 0.79 Mya (0.07–6.67 Mya, 95 % HPD). Estimates of gene flow between the neighboring regions were mostly low (2 Nm < 1). Estimates of effective population size decreased with southern latitudes: NEPR > SEPR > PAR. Conclusions Highly effective dispersal capabilities allow A. pompejana to overcome the temporal instability and intermittent distribution of active hydrothermal vents in the eastern Pacific Ocean. Consequently, the species exhibits very high levels of genetic diversity compared with many co-distributed vent annelids and mollusks. Nonetheless, its levels of genetic diversity in partially isolated populations are inversely correlated with tectonic spreading rates. As for many other vent taxa, this pioneering colonizer is similarly affected by local rates of habitat turnover and by major dispersal filters associated with the Equator and the Easter Microplate region. Electronic supplementary material The online version of this article (doi:10.1186/s12862-016-0807-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Sook-Jin Jang
- Interdisciplinary Program of EcoCreative, The Graduate School, Ewha Womans University, Seoul, South Korea
| | - Eunji Park
- Division of Ecoscience, Ewha Womans University, Seoul, South Korea
| | - Won-Kyung Lee
- Division of Ecoscience, Ewha Womans University, Seoul, South Korea
| | - Shannon B Johnson
- Monterey Bay Aquarium Research Institute, Moss Landing, CA, 95039-9644, USA
| | | | - Yong-Jin Won
- Interdisciplinary Program of EcoCreative, The Graduate School, Ewha Womans University, Seoul, South Korea. .,Division of Ecoscience, Ewha Womans University, Seoul, South Korea.
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Roterman CN, Copley JT, Linse KT, Tyler PA, Rogers AD. Connectivity in the cold: the comparative population genetics of vent-endemic fauna in the Scotia Sea, Southern Ocean. Mol Ecol 2016; 25:1073-88. [PMID: 26919308 DOI: 10.1111/mec.13541] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Revised: 12/19/2015] [Accepted: 12/24/2015] [Indexed: 01/18/2023]
Abstract
We report the first comparative population genetics study for vent fauna in the Southern Ocean using cytochrome C oxidase I and microsatellite markers. Three species are examined: the kiwaid squat lobster, Kiwa tyleri, the peltospirid gastropod, Gigantopelta chessoia, and a lepetodrilid limpet, Lepetodrilus sp., collected from vent fields 440 km apart on the East Scotia Ridge (ESR) and from the Kemp Caldera on the South Sandwich Island Arc, ~95 km eastwards. We report no differentiation for all species across the ESR, consistent with panmixia or recent range expansions. A lack of differentiation is notable for Kiwa tyleri, which exhibits extremely abbreviated lecithotrophic larval development, suggestive of a very limited dispersal range. Larval lifespans may, however, be extended by low temperature-induced metabolic rate reduction in the Southern Ocean, muting the impact of dispersal strategy on patterns of population structure. COI diversity patterns suggest all species experienced demographic bottlenecks or selective sweeps in the past million years and possibly at different times. ESR and Kemp limpets are divergent, although with evidence of very recent ESR-Kemp immigration. Their divergence, possibility indicative of incipient speciation, along with the absence of the other two species at Kemp, may be the consequence of differing dispersal capabilities across a ~1000 m depth range and/or different selective regimes between the two areas. Estimates of historic and recent limpet gene flow between the ESR and Kemp are consistent with predominantly easterly currents and potentially therefore, cross-axis currents on the ESR, with biogeographic implications for the region.
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Affiliation(s)
- C N Roterman
- Department of Zoology, University of Oxford, South Parks Road, Oxford, OX1 3PS, UK
| | - J T Copley
- Ocean and Earth Science, University of Southampton, Waterfront Campus, Southampton, SO14 3ZH, UK
| | - K T Linse
- British Antarctic Survey, High Cross, Madingley Road, Cambridge, CB3 0ET, UK
| | - P A Tyler
- Ocean and Earth Science, University of Southampton, Waterfront Campus, Southampton, SO14 3ZH, UK
| | - A D Rogers
- Department of Zoology, University of Oxford, South Parks Road, Oxford, OX1 3PS, UK
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Johnson SB, Won YJ, Harvey JB, Vrijenhoek RC. A hybrid zone between Bathymodiolus mussel lineages from eastern Pacific hydrothermal vents. BMC Evol Biol 2013; 13:21. [PMID: 23347448 PMCID: PMC3740784 DOI: 10.1186/1471-2148-13-21] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Accepted: 01/11/2013] [Indexed: 11/24/2022] Open
Abstract
Background The inhabitants of deep-sea hydrothermal vents occupy ephemeral island-like habitats distributed sporadically along tectonic spreading-centers, back-arc basins, and volcanically active seamounts. The majority of vent taxa undergo a pelagic larval phase, and thus varying degrees of geographical subdivision, ranging from no impedance of dispersal to complete isolation, often exist among taxa that span common geomorphological boundaries. Two lineages of Bathymodiolus mussels segregate on either side of the Easter Microplate, a boundary that separates the East Pacific Rise from spreading centers connected to the Pacific-Antarctic Ridge. Results A recent sample from the northwest flank of the Easter Microplate contained an admixture of northern and southern mitochondrial haplotypes and corresponding alleles at five nuclear gene loci. Genotypic frequencies in this sample did not fit random mating expectation. Significant heterozygote deficiencies at nuclear loci and gametic disequilibria between loci suggested that this transitional region might be a ‘Tension Zone’ maintained by immigration of parental types and possibly hybrid unfitness. An analysis of recombination history in the nuclear genes suggests a prolonged history of parapatric contact between the two mussel lineages. We hereby elevate the southern lineage to species status as Bathymodiolus antarcticus n. sp. and restrict the use of Bathymodiolus thermophilus to the northern lineage. Conclusions Because B. thermophilus s.s. exhibits no evidence for subdivision or isolation-by-distance across its 4000 km range along the EPR axis and Galápagos Rift, partial isolation of B. antarcticus n. sp. requires explanation. The time needed to produce the observed degree of mitochondrial differentiation is consistent with the age of the Easter Microplate (2.5 to 5.3 million years). The complex geomorphology of the Easter Microplate region forces strong cross-axis currents that might disrupt self-recruitment of mussels by removing planktotrophic larvae from the ridge axis. Furthermore, frequent local extinction events in this tectonically dynamic region might produce a demographic sink rather than a source for dispersing mussel larvae. Historical changes in tectonic rates and current patterns appear to permit intermittent contact and introgression between the two species.
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Affiliation(s)
- Shannon B Johnson
- Monterey Bay Aquarium Research Institute, Moss Landing, CA 95039-9644, USA.
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Cormier MH, MacDonald KC. East Pacific Rise 18°-19°S: Asymmetric spreading and ridge reorientation by ultrafast migration of axial discontinuities. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/93jb02382] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Rusby RI, Searle RC. A history of the Easter microplate, 5.25 Ma to present. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/94jb02779] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Kleinrock MC, Bird RT. Southeastern boundary of the Juan Fernandez microplate: Braking microplate rotation and deforming the Antarctic plate. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/93jb02510] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Perram LJ, Cormier MH, Macdonald KC. Magnetic and tectonic studies of the dueling propagating spreading centers at 20°40′S on the East Pacific Rise: Evidence for crustal rotations. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/92jb02913] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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11
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Lonsdale P. Geomorphology and structural segmentation of the crest of the southern (Pacific-Antarctic) East Pacific Rise. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/93jb02756] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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VRIJENHOEK ROBERTC. Genetic diversity and connectivity of deep-sea hydrothermal vent metapopulations. Mol Ecol 2010; 19:4391-411. [DOI: 10.1111/j.1365-294x.2010.04789.x] [Citation(s) in RCA: 151] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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13
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Tentler T, Acocella V. How does the initial configuration of oceanic ridge segments affect their interaction? Insights from analogue models. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2008jb006269] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Faure B, Jollivet D, Tanguy A, Bonhomme F, Bierne N. Speciation in the deep sea: multi-locus analysis of divergence and gene flow between two hybridizing species of hydrothermal vent mussels. PLoS One 2009; 4:e6485. [PMID: 19649261 PMCID: PMC2715857 DOI: 10.1371/journal.pone.0006485] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2009] [Accepted: 05/13/2009] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Reconstructing the history of divergence and gene flow between closely-related organisms has long been a difficult task of evolutionary genetics. Recently, new approaches based on the coalescence theory have been developed to test the existence of gene flow during the process of divergence. The deep sea is a motivating place to apply these new approaches. Differentiation by adaptation can be driven by the heterogeneity of the hydrothermal environment while populations should not have been strongly perturbed by climatic oscillations, the main cause of geographic isolation at the surface. METHODOLOGY/PRINCIPAL FINDING Samples of DNA sequences were obtained for seven nuclear loci and a mitochondrial locus in order to conduct a multi-locus analysis of divergence and gene flow between two closely related and hybridizing species of hydrothermal vent mussels, Bathymodiolus azoricus and B. puteoserpentis. The analysis revealed that (i) the two species have started to diverge approximately 0.760 million years ago, (ii) the B. azoricus population size was 2 to 5 time greater than the B. puteoserpentis and the ancestral population and (iii) gene flow between the two species occurred over the complete species range and was mainly asymmetric, at least for the chromosomal regions studied. CONCLUSIONS/SIGNIFICANCE A long history of gene flow has been detected between the two Bathymodiolus species. However, it proved very difficult to conclusively distinguish secondary introgression from ongoing parapatric differentiation. As powerful as coalescence approaches could be, we are left by the fact that natural populations often deviates from standard assumptions of the underlying model. A more direct observation of the history of recombination at one of the seven loci studied suggests an initial period of allopatric differentiation during which recombination was blocked between lineages. Even in the deep sea, geographic isolation may well be a crucial promoter of speciation.
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Klein EM, Smith DK, Williams CM, Schouten H. Counter-rotating microplates at the Galapagos triple junction. Nature 2005; 433:855-8. [PMID: 15729339 DOI: 10.1038/nature03262] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2004] [Accepted: 11/30/2004] [Indexed: 11/08/2022]
Abstract
An 'incipient' spreading centre east of (and orthogonal to) the East Pacific Rise at 2 degrees 40' N has been identified as forming a portion of the northern boundary of the Galapagos microplate. This spreading centre was described as a slowly diverging, westward propagating rift, tapering towards the East Pacific Rise. Here we present evidence that the 'incipient rift' has also rifted towards the east and opens anticlockwise about a pivot at its eastern end. The 'incipient rift' then bounds a second microplate, north of the clockwise-rotating Galapagos microplate. The Galapagos triple junction region, in the eastern equatorial Pacific Ocean, thus consists of two counter-rotating microplates partly separated by the Hess Deep rift. Our kinematic solution for microplate motion relative to the major plates indicates that the two counter-rotating microplates may be treated as rigid blocks driven by drag on the microplates' edges3.
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Affiliation(s)
- Emily M Klein
- Nicholas School of the Environment and Earth Sciences, Duke University, Durham, North Carolina 27708-0227, USA.
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Hurtado LA, Lutz RA, Vrijenhoek RC. Distinct patterns of genetic differentiation among annelids of eastern Pacific hydrothermal vents. Mol Ecol 2004; 13:2603-15. [PMID: 15315674 DOI: 10.1111/j.1365-294x.2004.02287.x] [Citation(s) in RCA: 103] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Population genetic and phylogenetic analyses of mitochondrial COI from five deep-sea hydrothermal vent annelids provided insights into their dispersal modes and barriers to gene flow. These polychaetes inhabit vent fields located along the East Pacific Rise (EPR) and Galapagos Rift (GAR), where hundreds to thousands of kilometers can separate island-like populations. Long-distance dispersal occurs via larval stages, but larval life histories differ among these taxa. Mitochondrial gene flow between populations of Riftia pachyptila, a siboglinid worm with neutrally buoyant lecithothrophic larvae, is diminished across the Easter Microplate region, which lies at the boundary of Indo-Pacific and Antarctic deep-sea provinces. Populations of the siboglinid Tevnia jerichonana are similarly subdivided. Oasisia alvinae is not found on the southern EPR, but northern EPR populations of this siboglinid are subdivided across the Rivera Fracture Zone. Mitochondrial gene flow of Alvinella pompejana, an alvinellid with large negatively buoyant lecithotrophic eggs and arrested embryonic development, is unimpeded across the Easter Microplate region. Gene flow in the polynoid Branchipolynoe symmytilida also is unimpeded across the Easter Microplate region. However, A. pompejana populations are subdivided across the equator, whereas B. symmitilida populations are subdivided between the EPR and GAR axes. The present findings are compared with similar evidence from codistributed species of annelids, molluscs and crustaceans to identify potential dispersal filters in these eastern Pacific ridge systems.
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Affiliation(s)
- L A Hurtado
- Monterey Bay Aquarium Research Institute, 7700 Sandholdt Road, Moss Landing, CA 95039, USA.
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Won Y, Young CR, Lutz RA, Vrijenhoek RC. Dispersal barriers and isolation among deep-sea mussel populations (Mytilidae: Bathymodiolus) from eastern Pacific hydrothermal vents. Mol Ecol 2003; 12:169-84. [PMID: 12492886 DOI: 10.1046/j.1365-294x.2003.01726.x] [Citation(s) in RCA: 114] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Deep-sea hydrothermal vent species are widely dispersed among habitat islands found along the global mid-ocean ridge system. We examine factors that affect population structure, gene flow and isolation in vent-endemic mussels of the genus Bathymodiolus from the eastern Pacific Ocean. Mussels were sampled from localities including the Galapagos Rift (GAR, 0 degrees 48' N; 86 degrees 10' W) and the East Pacific Rise (EPR, 13 degrees N to 32 degrees S latitude) across a maximum distance of 4900 km. The sampled range crossed a series of topographical features that interrupt linear aspects of the ridge system, and it encompassed regions of strong cross-axis currents that could impede along-axis dispersal of mussel larvae. Examinations of mitochondrial DNA sequences and allozyme variation revealed significant barriers to gene flow along the ridge axis. All populations from the GAR and EPR from 13 degrees N to 11 degrees S were homogeneous genetically and appeared to experience unimpeded high levels of interpopulational gene flow. In contrast, mussels from north and south of the Easter Microplate were highly divergent (4.4%), possibly comprising sister-species that diverged after formation of the microplate approximately 4.5 Ma. Strong cross-axis currents associated with inflated bathymetry of the microplate region may reinforce isolation across this region.
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Affiliation(s)
- Y Won
- Monterey Bay Aquarium Research Institute, 7700 Sandholdt Road, Moss Landing, CA 95039-0628, USA
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Baker ET, Hey RN, Lupton JE, Resing JA, Feely RA, Gharib JJ, Massoth GJ, Sansone FJ, Kleinrock M, Martinez F, Naar DF, Rodrigo C, Bohnenstiehl D, Pardee D. Hydrothermal venting along Earth's fastest spreading center: East Pacific Rise, 27.5°-32.3°. ACTA ACUST UNITED AC 2002. [DOI: 10.1029/2001jb000651] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- E. T. Baker
- Pacific Marine Environmental Laboratory; NOAA; Seattle Washington USA
| | - R. N. Hey
- Hawaii Institute of Geophysics and Planetology; University of Hawaii; Honolulu Hawaii USA
| | - J. E. Lupton
- Pacific Marine Environmental Laboratory; NOAA; Newport Oregon USA
| | - J. A. Resing
- Joint Institute for the Study of the Atmosphere and Ocean; University of Washington; Seattle Washington USA
| | - R. A. Feely
- Pacific Marine Environmental Laboratory; NOAA; Seattle Washington USA
| | - J. J. Gharib
- Department of Oceanography; University of Hawaii; Honolulu Hawaii USA
| | - G. J. Massoth
- Pacific Marine Environmental Laboratory; NOAA; Seattle Washington USA
| | - F. J. Sansone
- Department of Oceanography; University of Hawaii; Honolulu Hawaii USA
| | - M. Kleinrock
- Department of Geology; Vanderbilt University; Nashville Tennessee USA
| | - F. Martinez
- Hawaii Institute of Geophysics and Planetology; University of Hawaii; Honolulu Hawaii USA
| | - D. F. Naar
- Department of Marine Science; University of South Florida; St. Petersburg Florida USA
| | - C. Rodrigo
- Servicio Hidrografico y Oceanografico de la Armada; Valparaiso Chile
| | - D. Bohnenstiehl
- Department of Geology; Vanderbilt University; Nashville Tennessee USA
| | - D. Pardee
- Hawaii Institute of Geophysics and Planetology; University of Hawaii; Honolulu Hawaii USA
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Manighetti I, Tapponnier P, Courtillot V, Gallet Y, Jacques E, Gillot PY. Strain transfer between disconnected, propagating rifts in Afar. ACTA ACUST UNITED AC 2001. [DOI: 10.1029/2000jb900454] [Citation(s) in RCA: 102] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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20
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Kingsley RH, Schilling JG. Plume-ridge interaction in the Easter-Salas y Gomez seamount chain-Easter Microplate system: Pb isotope evidence. ACTA ACUST UNITED AC 1998. [DOI: 10.1029/98jb01496] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Nakanishi M, Winterer EL. Tectonic history of the Pacific-Farallon-Phoenix triple junction from Late Jurassic to Early Cretaceous: An abandoned Mesozoic spreading system in the Central Pacific Basin. ACTA ACUST UNITED AC 1998. [DOI: 10.1029/98jb00754] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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22
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Bird RT, Naar DF, Larson RL, Searle RC, Scotese CR. Plate tectonic reconstructions of the Juan Fernandez microplate: Transformation from internal shear to rigid rotation. ACTA ACUST UNITED AC 1998. [DOI: 10.1029/97jb02133] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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23
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Kruse SE, Liu ZJ, Naar DF, Duncan RA. Effective elastic thickness of the lithosphere along the Easter Seamount Chain. ACTA ACUST UNITED AC 1997. [DOI: 10.1029/97jb02158] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Tebbens SF, Cande SC, Kovacs L, Parra JC, LaBrecque JL, Vergara H. The Chile ridge: A tectonic framework. ACTA ACUST UNITED AC 1997. [DOI: 10.1029/96jb02581] [Citation(s) in RCA: 103] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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