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Hänfling B, Smith A. The genome sequence of the nine-spined stickleback, Pungitius pungitius (Linnaeus, 1758). Wellcome Open Res 2023; 8:555. [PMID: 39114814 PMCID: PMC11303943 DOI: 10.12688/wellcomeopenres.20354.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/02/2023] [Indexed: 08/10/2024] Open
Abstract
We present a genome assembly from an individual male Pungitius pungitius (the nine-spined stickleback; Chordata; Actinopteri; Gasterosteiformes; Gasterosteidae). The genome sequence is 480.4 megabases in span. Most of the assembly is scaffolded into 21 chromosomal pseudomolecules. The mitochondrial genome has also been assembled and is 16.57 kilobases in length.
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Affiliation(s)
- Bernd Hänfling
- Institute for Biodiversity and Freshwater Conservation, University of Highlands and Islands, Inverness, Scotland, UK
| | - Alan Smith
- School of Natural Sciences, University of Hull, Hull, England, UK
| | | | | | - Tree of Life Core Informatics collective
- Institute for Biodiversity and Freshwater Conservation, University of Highlands and Islands, Inverness, Scotland, UK
- School of Natural Sciences, University of Hull, Hull, England, UK
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2
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Krieg CP, Chambers SM. The ecology and physiology of fern gametophytes: A methodological synthesis. APPLICATIONS IN PLANT SCIENCES 2022; 10:e11464. [PMID: 35495196 PMCID: PMC9039797 DOI: 10.1002/aps3.11464] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2021] [Revised: 12/21/2021] [Accepted: 01/10/2022] [Indexed: 05/14/2023]
Abstract
All green plants alternate between the gametophyte and sporophyte life stages, but only seed-free vascular plants (ferns and lycophytes) have independent, free-living gametophytes. Fern and lycophyte gametophytes are significantly reduced in size and morphological complexity relative to their sporophytic counterparts and have often been overlooked in ecological and physiological studies. Understanding the ecological and physiological factors that directly impact this life stage is of critical importance because the ultimate existence of a sporophyte is dependent upon successful fertilization in the gametophyte generation. Furthermore, previous research has shown that the dual nature of the life cycle and the high dispersibility of spores can result in different geographic patterns between gametophytes and their respective sporophytes. This variation in distribution patterns likely exacerbates the separation of selective pressures acting on gametophyte and sporophyte generations, and can uniquely impact a species' ecology and physiology. Here, we provide a review of historical and contemporary methodologies used to examine ecological and physiological aspects of fern gametophytes, as well as those that allow for comparisons between the two generations. We conclude by suggesting methodological approaches to answer currently outstanding questions. We hope that the information covered herein will serve as a guide to current researchers and stimulate future discoveries in fern gametophyte ecology and physiology.
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Affiliation(s)
| | - Sally M. Chambers
- Department of BotanyMarie Selby Botanical GardensSarasotaFlorida34236USA
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3
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Denys GPJ, Persat H, Dettai A, Geiger MF, Freyhof J, Fesquet J, Keith P. Genetic and morphological discrimination of three species of ninespined stickleback Pungitius
spp. (Teleostei, Gasterosteidae) in France with the revalidation of Pungitius vulgaris
(Mauduyt, 1848). J ZOOL SYST EVOL RES 2017. [DOI: 10.1111/jzs.12178] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Gaël P. J. Denys
- Unité Biologie des organismes et écosystèmes aquatiques (BOREA, UMR 7208); Sorbonne Universités; Muséum national d'Histoire naturelle; Université Pierre et Marie Curie; Université de Caen Basse-Normandie; CNRS; IRD; Paris France
| | - Henri Persat
- Écologie des Hydrosystèmes Naturels et Anthropisés; LEHNA UMR 5023; Bat. Forel; Université Claude Bernard Lyon 1; Villeurbanne Cedex France
| | - Agnès Dettai
- Institut de Systématique, Evolution, Biodiversité; ISYEB - UMR 7205 - CNRS; MNHN; UPMC; EPHE; Muséum national d'Histoire naturelle; Sorbonne Universités; Paris France
| | - Matthias F. Geiger
- Zoologisches Forschungsmuseum Alexander Koenig; Leibniz Institute for Animal Biodiversity; Bonn Germany
| | - Jörg Freyhof
- Leibniz Institute of Freshwater Ecology and Inland Fisheries; Berlin Germany
| | - Justine Fesquet
- Unité Biologie des organismes et écosystèmes aquatiques (BOREA, UMR 7208); Sorbonne Universités; Muséum national d'Histoire naturelle; Université Pierre et Marie Curie; Université de Caen Basse-Normandie; CNRS; IRD; Paris France
| | - Philippe Keith
- Unité Biologie des organismes et écosystèmes aquatiques (BOREA, UMR 7208); Sorbonne Universités; Muséum national d'Histoire naturelle; Université Pierre et Marie Curie; Université de Caen Basse-Normandie; CNRS; IRD; Paris France
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4
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Allometric analysis of a morphological anti-predator trait in geographic populations of Japanese crucian carp. Sci Rep 2017; 7:41943. [PMID: 28150742 PMCID: PMC5288778 DOI: 10.1038/srep41943] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Accepted: 12/29/2016] [Indexed: 11/17/2022] Open
Abstract
Costly anti-predator traits tend to be expressed only in high-predation conditions. For the cyprinid fish genus Carassius, deeper body depth is more adaptive to avoid predation by gape-limited piscivorous fish, but it raises swimming costs. It is therefore predicted that the relative body depth will decrease when the prey fish has reached a size larger than the predator gape-size. This prediction was tested by allometric analysis of the relation between body depth and standard length of triploid asexual females of the Japanese crucian carp (Carassius auratus sspp.) sampled from 13 geographic populations. The overall allometric relation was not significantly different from isometry. The estimate of the common major-axis slope was close to 1 (near-isometry). The mean relative body depth differed significantly among populations. A significant positive correlation was found with the mean annual air temperature. The geographic variation suggests that local selection pressures vary. In conclusion, the hypothesis that larger fish will have lower body depth was not supported, perhaps indicating that deep body depth in large fish is adaptive for some reason other than defense against piscivorous fish.
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Wang C, Agrawal S, Laudien J, Häussermann V, Held C. Discrete phenotypes are not underpinned by genome-wide genetic differentiation in the squat lobster Munida gregaria (Crustacea: Decapoda: Munididae): a multi-marker study covering the Patagonian shelf. BMC Evol Biol 2016; 16:258. [PMID: 27903261 PMCID: PMC5131467 DOI: 10.1186/s12862-016-0836-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Accepted: 11/21/2016] [Indexed: 12/02/2022] Open
Abstract
BACKGROUND DNA barcoding has demonstrated that many discrete phenotypes are in fact genetically distinct (pseudo)cryptic species. Genetically identical, isogenic individuals, however, can also express similarly different phenotypes in response to a trigger condition, e.g. in the environment. This alternative explanation to cryptic speciation often remains untested because it requires considerable effort to reject the hypothesis that the observed underlying genetic homogeneity of the different phenotypes may be trivially caused by too slowly evolving molecular markers. The widespread squat lobster Munida gregaria comprises two discrete ecotypes, gregaria s. str. and subrugosa, which were long regarded as different species due to marked differences in morphological, ecological and behavioral traits. We studied the morphometry and genetics of M. gregaria s. l. and tested (1) whether the phenotypic differences remain stable after continental-scale sampling and inclusion of different life stages, (2) and whether each phenotype is underpinned by a specific genotype. RESULTS A total number of 219 gregaria s. str. and subrugosa individuals from 25 stations encompassing almost entire range in South America were included in morphological and genetic analyses using nine unlinked hypervariable microsatellites and new COI sequences. Results from the PCA and using discriminant functions demonstrated that the morphology of the two forms remains discrete. The mitochondrial data showed a shallow, star-like haplotype network and complete overlap of genetic distances within and among ecotypes. Coalescent-based species delimitation methods, PTP and GMYC, coherently suggested that haplotypes of both ecotypes forms a single species. Although all microsatellite markers possess sufficient genetic variation, AMOVA, PCoA and Bayesian clustering approaches revealed no genetic clusters corresponding to ecotypes or geographic units across the entire South-American distribution. No evidence of isolation-by-distance could be detected for this species in South America. CONCLUSIONS Despite their pronounced bimodal morphologies and different lifestyles, the gregaria s. str. and subrugosa ecotypes form a single, dimorphic species M. gregaria s. l.. Based on adequate geographic coverage and multiple independent polymorphic loci, there is no indication that each phenotype may have a unique genetic basis, leaving phenotypic plasticity or localized genomic islands of speciation as possible explanations.
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Affiliation(s)
- Chen Wang
- Alfred Wegener Institute, Helmholtz Center for Polar- and Marine Research, Am Handelshafen 12, 27570 Bremerhaven, Germany
| | - Shobhit Agrawal
- Alfred Wegener Institute, Helmholtz Center for Polar- and Marine Research, Am Handelshafen 12, 27570 Bremerhaven, Germany
| | - Jürgen Laudien
- Alfred Wegener Institute, Helmholtz Center for Polar- and Marine Research, Am Handelshafen 12, 27570 Bremerhaven, Germany
| | - Vreni Häussermann
- Universidad Católica de Valparaíso, Facultad de Recursos Naturales, Escuela de Ciencias del Mar, Avda. Brasil 2950, Valparaíso, Chile
- Huinay Scientific Field Station, Huinay, Los Lagos Chile
| | - Christoph Held
- Alfred Wegener Institute, Helmholtz Center for Polar- and Marine Research, Am Handelshafen 12, 27570 Bremerhaven, Germany
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Ozerov MY, Himberg M, Aykanat T, Sendek DS, Hägerstrand H, Verliin A, Krause T, Olsson J, Primmer CR, Vasemägi A. Generation of a neutral F
ST
baseline for testing local adaptation on gill raker number within and between European whitefish ecotypes in the Baltic Sea basin. J Evol Biol 2015; 28:1170-83. [DOI: 10.1111/jeb.12645] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Revised: 04/09/2015] [Accepted: 04/10/2015] [Indexed: 01/17/2023]
Affiliation(s)
- M. Y. Ozerov
- Department of Biology; University of Turku; Turku Finland
| | - M. Himberg
- Faculty of Science and Engineering; Åbo Akademi University; Turku Finland
| | - T. Aykanat
- Department of Biology; University of Turku; Turku Finland
| | - D. S. Sendek
- State Research Institute on Lake and River Fisheries (GosNIORKh); St. Petersburg Russia
| | - H. Hägerstrand
- Faculty of Science and Engineering; Åbo Akademi University; Turku Finland
| | - A. Verliin
- Estonian Marine Institute; University of Tartu; Tartu Estonia
| | - T. Krause
- Institute of Agricultural and Environmental Sciences; Estonian University of Life Sciences; Tartu Estonia
| | - J. Olsson
- Department of Aquatic Resources; Institute for Coastal Research; Swedish University of Agricultural Sciences; Öregrund Sweden
| | - C. R. Primmer
- Department of Biology; University of Turku; Turku Finland
| | - A. Vasemägi
- Department of Biology; University of Turku; Turku Finland
- Institute of Agricultural and Environmental Sciences; Estonian University of Life Sciences; Tartu Estonia
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7
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Bruneaux M, Nikinmaa M, Laine VN, Lindström K, Primmer CR, Vasemägi A. Differences in the metabolic response to temperature acclimation in nine-spined stickleback (Pungitius pungitius) populations from contrasting thermal environments. ACTA ACUST UNITED AC 2014; 321:550-65. [PMID: 25389079 DOI: 10.1002/jez.1889] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Revised: 07/27/2014] [Accepted: 08/06/2014] [Indexed: 11/06/2022]
Abstract
Metabolic responses to temperature changes are crucial for maintaining the energy balance of an individual under seasonal temperature fluctuations. To understand how such responses differ in recently isolated populations (<11,000 years), we studied four Baltic populations of the nine-spined stickleback (Pungitius pungitius L.) from coastal locations (seasonal temperature range, 0-29°C) and from colder, more thermally stable spring-fed ponds (1-19°C). Salinity and predation pressure also differed between these locations. We acclimatized wild-caught fish to 6, 11, and 19°C in common garden conditions for 4-6 months and determined their aerobic scope and hepatosomatic index (HSI). The freshwater fish from the colder (2-14°C), predator-free pond population exhibited complete temperature compensation for their aerobic scope, whereas the coastal populations underwent metabolic rate reduction during the cold treatment. Coastal populations had higher HSI than the colder pond population at all temperatures, with cold acclimation accentuating this effect. The metabolic rates and HSI for freshwater fish from the pond with higher predation pressure were more similar to those of the coastal ones. Our results suggest that ontogenic effects and/or genetic differentiation are responsible for differential energy storage and metabolic responses between these populations. This work demonstrates the metabolic versatility of the nine-spined stickleback and the pertinence of an energetic framework to better understand potential local adaptations. It also demonstrates that instead of using a single acclimation temperature thermal reaction norms should be compared when studying individuals originating from different thermal environments in a common garden setting.
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Affiliation(s)
- Matthieu Bruneaux
- Division of Genetics and Physiology, Department of Biology, University of Turku, Turku, Finland
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8
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Yang J, Shikano T, Li MH, Merilä J. Genome-wide linkage disequilibrium in nine-spined stickleback populations. G3 (BETHESDA, MD.) 2014; 4:1919-29. [PMID: 25122668 PMCID: PMC4199698 DOI: 10.1534/g3.114.013334] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Accepted: 08/09/2014] [Indexed: 11/18/2022]
Abstract
Variation in the extent and magnitude of genome-wide linkage disequilibrium (LD) among populations residing in different habitats has seldom been studied in wild vertebrates. We used a total of 109 microsatellite markers to quantify the level and patterns of genome-wide LD in 13 Fennoscandian nine-spined stickleback (Pungitius pungitius) populations from four (viz. marine, lake, pond, and river) different habitat types. In general, high magnitude (D' > 0.5) of LD was found both in freshwater and marine populations, and the magnitude of LD was significantly greater in inland freshwater than in marine populations. Interestingly, three coastal freshwater populations located in close geographic proximity to the marine populations exhibited similar LD patterns and genetic diversity as their marine neighbors. The greater levels of LD in inland freshwater compared with marine and costal freshwater populations can be explained in terms of their contrasting demographic histories: founder events, long-term isolation, small effective sizes, and population bottlenecks are factors likely to have contributed to the high levels of LD in the inland freshwater populations. In general, these findings shed new light on the patterns and extent of variation in genome-wide LD, as well as the ecological and evolutionary factors driving them.
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Affiliation(s)
- Ji Yang
- CAS Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences (CAS), Beijing 100101, China
| | - Takahito Shikano
- Ecological Genetics Research Unit, Department of Biosciences, FIN-00014 University of Helsinki, Finland
| | - Meng-Hua Li
- CAS Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences (CAS), Beijing 100101, China
| | - Juha Merilä
- Ecological Genetics Research Unit, Department of Biosciences, FIN-00014 University of Helsinki, Finland
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9
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Monzón-Argüello C, Consuegra S, Gajardo G, Marco-Rius F, Fowler DM, DeFaveri J, Garcia de Leaniz C. Contrasting patterns of genetic and phenotypic differentiation in two invasive salmonids in the southern hemisphere. Evol Appl 2014; 7:921-36. [PMID: 25469171 PMCID: PMC4211722 DOI: 10.1111/eva.12188] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Accepted: 06/15/2014] [Indexed: 01/31/2023] Open
Abstract
Invasion success may be expected to increase with residence time (i.e., time since first introduction) and secondary releases (i.e., those that follow the original introduction), but this has rarely been tested in natural fish populations. We compared genetic and phenotypic divergence in rainbow trout and brown trout in Chile and the Falkland Islands to test the prediction that adaptive divergence, measured as PST/FST, would increase with residence time and secondary releases. We also explored whether interspecific competition between invaders could drive phenotypic divergence. Residence time had no significant effect on genetic diversity, phenotypic divergence, effective population size, or signatures of expansion of invasive trout. In contrast, secondary releases had a major effect on trout invasions, and rainbow trout populations mostly affected by aquaculture escapees showed significant divergence from less affected populations. Coexistence with brown trout had a positive effect on phenotypic divergence of rainbow trout. Our results highlight an important role of secondary releases in shaping fish invasions, but do not support the contention that older invaders are more differentiated than younger ones. They also suggest that exotic trout may not have yet developed local adaptations in these recently invaded habitats, at least with respect to growth-related traits.
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Affiliation(s)
| | | | - Gonzalo Gajardo
- Laboratorio de Genética, Acuicultura y Biodiversidad, Universidad de Los Lagos Osorno, Chile
| | | | | | - Jacquelin DeFaveri
- Ecological Genetics Research Unit, Department of Biosciences, University of Helsinki Helsinki, Finland
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10
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DeFaveri J, Merilä J. Evidence for adaptive phenotypic differentiation in Baltic Sea sticklebacks. J Evol Biol 2013; 26:1700-15. [DOI: 10.1111/jeb.12168] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2013] [Revised: 03/26/2013] [Accepted: 03/27/2013] [Indexed: 12/26/2022]
Affiliation(s)
- J. DeFaveri
- Ecological Genetics Research Unit; Department of Biosciences; University of Helsinki; Helsinki Finland
| | - J. Merilä
- Ecological Genetics Research Unit; Department of Biosciences; University of Helsinki; Helsinki Finland
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11
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Lenz TL, Eizaguirre C, Kalbe M, Milinski M. EVALUATING PATTERNS OF CONVERGENT EVOLUTION AND TRANS-SPECIES POLYMORPHISM AT MHC IMMUNOGENES IN TWO SYMPATRIC STICKLEBACK SPECIES. Evolution 2013; 67:2400-12. [DOI: 10.1111/evo.12124] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2012] [Accepted: 03/26/2013] [Indexed: 01/15/2023]
Affiliation(s)
- Tobias L. Lenz
- Department of Evolutionary Ecology; Max Planck Institute for Evolutionary Biology; August-Thienemann-Str 2 24306 Plön Germany
| | - Christophe Eizaguirre
- Department of Evolutionary Ecology; Max Planck Institute for Evolutionary Biology; August-Thienemann-Str 2 24306 Plön Germany
- Department of Evolutionary Ecology of Marine Fishes; GEOMAR
- Helmholtz Center for Ocean Research; Düsternbrooker Weg 20 24105 Kiel Germany
| | - Martin Kalbe
- Department of Evolutionary Ecology; Max Planck Institute for Evolutionary Biology; August-Thienemann-Str 2 24306 Plön Germany
| | - Manfred Milinski
- Department of Evolutionary Ecology; Max Planck Institute for Evolutionary Biology; August-Thienemann-Str 2 24306 Plön Germany
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12
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Merilä J. Nine-spined stickleback (Pungitius pungitius): an emerging model for evolutionary biology research. Ann N Y Acad Sci 2013; 1289:18-35. [DOI: 10.1111/nyas.12089] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Juha Merilä
- Ecological Genetics Research Unit, Department of Biosciences; University of Helsinki; Helsinki; Finland
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13
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Välimäki K, Herczeg G, Merilä J. Morphological anti-predator defences in the nine-spined stickleback: constitutive, induced or both? Biol J Linn Soc Lond 2012. [DOI: 10.1111/j.1095-8312.2012.01989.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Kaisa Välimäki
- Ecological Genetics Research Unit; University Helsinki; PO Box 65; FI-00014; Helsinki; Finland
| | - Gábor Herczeg
- Ecological Genetics Research Unit; University Helsinki; PO Box 65; FI-00014; Helsinki; Finland
| | - Juha Merilä
- Ecological Genetics Research Unit; University Helsinki; PO Box 65; FI-00014; Helsinki; Finland
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14
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Ab Ghani NI, Herczeg G, Merilä J. Body size divergence in nine-spined sticklebacks: disentangling additive genetic and maternal effects. Biol J Linn Soc Lond 2012. [DOI: 10.1111/j.1095-8312.2012.01956.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- Nurul Izza Ab Ghani
- Ecological Genetics Research Unit; Department of Biosciences; University of Helsinki; PO Box 65 FI-00014 Helsinki Finland
| | - Gábor Herczeg
- Ecological Genetics Research Unit; Department of Biosciences; University of Helsinki; PO Box 65 FI-00014 Helsinki Finland
| | - Juha Merilä
- Ecological Genetics Research Unit; Department of Biosciences; University of Helsinki; PO Box 65 FI-00014 Helsinki Finland
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15
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Lindgren AR, Pankey MS, Hochberg FG, Oakley TH. A multi-gene phylogeny of Cephalopoda supports convergent morphological evolution in association with multiple habitat shifts in the marine environment. BMC Evol Biol 2012; 12:129. [PMID: 22839506 PMCID: PMC3733422 DOI: 10.1186/1471-2148-12-129] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2012] [Accepted: 07/05/2012] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND The marine environment is comprised of numerous divergent organisms living under similar selective pressures, often resulting in the evolution of convergent structures such as the fusiform body shape of pelagic squids, fishes, and some marine mammals. However, little is known about the frequency of, and circumstances leading to, convergent evolution in the open ocean. Here, we present a comparative study of the molluscan class Cephalopoda, a marine group known to occupy habitats from the intertidal to the deep sea. Several lineages bear features that may coincide with a benthic or pelagic existence, making this a valuable group for testing hypotheses of correlated evolution. To test for convergence and correlation, we generate the most taxonomically comprehensive multi-gene phylogeny of cephalopods to date. We then create a character matrix of habitat type and morphological characters, which we use to infer ancestral character states and test for correlation between habitat and morphology. RESULTS Our study utilizes a taxonomically well-sampled phylogeny to show convergent evolution in all six morphological characters we analyzed. Three of these characters also correlate with habitat. The presence of an autogenic photophore (those relying upon autonomous enzymatic light reactions) is correlated with a pelagic habitat, while the cornea and accessory nidamental gland correlate with a benthic lifestyle. Here, we present the first statistical tests for correlation between convergent traits and habitat in cephalopods to better understand the evolutionary history of characters that are adaptive in benthic or pelagic environments, respectively. DISCUSSION Our study supports the hypothesis that habitat has influenced convergent evolution in the marine environment: benthic organisms tend to exhibit similar characteristics that confer protection from invasion by other benthic taxa, while pelagic organisms possess features that facilitate crypsis and communication in an environment lacking physical refuges. Features that have originated multiple times in distantly related lineages are likely adaptive for the organisms inhabiting a particular environment: studying the frequency and evolutionary history of such convergent characters can increase understanding of the underlying forces driving ecological and evolutionary transitions in the marine environment.
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Affiliation(s)
- Annie R Lindgren
- Department of Ecology, Evolution, and Marine Biology, University of California, Santa Barbara, CA 93106, USA
- Present Address: Department of Biology, Portland State University, PO Box 751, Portland, OR 97207, USA
| | - Molly S Pankey
- Department of Ecology, Evolution, and Marine Biology, University of California, Santa Barbara, CA 93106, USA
| | - Frederick G Hochberg
- Department of Invertebrate Zoology, Santa Barbara Museum of Natural History, 2559 Puesta del Sol Rd, Santa Barbara, CA, 93105, USA
| | - Todd H Oakley
- Department of Ecology, Evolution, and Marine Biology, University of California, Santa Barbara, CA 93106, USA
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16
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Leinonen T, McCairns RJS, Herczeg G, Merilä J. MULTIPLE EVOLUTIONARY PATHWAYS TO DECREASED LATERAL PLATE COVERAGE IN FRESHWATER THREESPINE STICKLEBACKS. Evolution 2012. [DOI: 10.1111/j.1558-5646.2012.01724.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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