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Sepúlveda-Espinoza F, Cofré-Serrano A, Veloso-Valeria T, Quesada-Calderon S, Guillemin ML. Characterization of the organellar genomes of Mazzaella laminarioides and Mazaella membranacea (Gigartinaceae, Rhodophyta). JOURNAL OF PHYCOLOGY 2024. [PMID: 38944824 DOI: 10.1111/jpy.13478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Revised: 05/08/2024] [Accepted: 05/28/2024] [Indexed: 07/02/2024]
Abstract
Mazzaella, a genus with no genomic resources available, has extensive distribution in the cold waters of the Pacific, where they represent ecologically and economically important species. In this study, we aimed to sequence, assemble, and annotate the complete mitochondrial and chloroplast genomes from two Mazzaella spp. and characterize the intraspecific variation among them. We report for the first time seven whole organellar genomes (mitochondria: OR915856, OR947465, OR947466, OR947467, OR947468, OR947469, OR947470; chloroplast: OR881974, OR909680, OR909681, OR909682, OR909683, OR909684, OR909685) obtained through high-throughput sequencing for six M. laminarioides sampled from three Chilean regions and one M. membranacea. Sequenced Mazzaella mitogenomes have identical gene number, gene order, and genome structure. The same results were observed for assembled plastomes. A total of 52 genes were identified in mitogenomes, and a total of 235 genes were identified in plastomes. Although the M. membranacea plastome included a full-length pbsA gene, in all M. laminarioides samples, the pbsA gene was split in three open reading frames (ORFs). Within M. laminarioides, we observed important plastome lineage-specific variations, such as the pseudogenization of the two hypothetical protein-coding genes, ycf23 and ycf45. Nonsense mutations in the ycf23 and ycf45 genes were only detected in the northern lineage. These results are consistent with phylogenetic reconstructions and divergence time estimation using concatenated coding sequences that not only support the monophyly of M. laminarioides but also underscore that the three M. laminarioides lineages are in an advanced stage of divergence. These new results open the question of the existence of still undisclosed species in M. laminarioides.
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Affiliation(s)
- Francisco Sepúlveda-Espinoza
- Facultad de Ciencias, Instituto de Ciencias Ambientales y Evolutivas, Universidad Austral de Chile, Valdivia, Chile
- Laboratorio de Epigenética Vegetal, Facultad de Ciencias Forestales, Universidad de Concepción, Concepción, Chile
| | - Angela Cofré-Serrano
- Facultad de Ciencias, Instituto de Ciencias Ambientales y Evolutivas, Universidad Austral de Chile, Valdivia, Chile
| | - Tomás Veloso-Valeria
- Facultad de Ciencias, Instituto de Ciencias Ambientales y Evolutivas, Universidad Austral de Chile, Valdivia, Chile
| | - Suany Quesada-Calderon
- Facultad de Ciencias, Instituto de Ciencias Ambientales y Evolutivas, Universidad Austral de Chile, Valdivia, Chile
- AUSTRAL-Omics, Vicerrectoría de Investigación, desarrollo y creación artística (VIDCA), Universidad Austral de Chile, Valdivia, Chile
| | - Marie-Laure Guillemin
- Facultad de Ciencias, Instituto de Ciencias Ambientales y Evolutivas, Universidad Austral de Chile, Valdivia, Chile
- Núcleo Milenio MASH, Instituto de Ciencias Ambientales y Evolutivas, Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile
- Centro FONDAP de Investigación en Dinámica de Ecosistemas Marinos de Altas Latitudes (IDEAL), Valdivia, Chile
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Huanel OR, Montecinos AE, Sepúlveda-Espinoza F, Guillemin ML. Impact of persistent barrier to gene flow and catastrophic events on red algae evolutionary history along the Chilean coast. Front Genet 2024; 15:1336427. [PMID: 38525243 PMCID: PMC10957783 DOI: 10.3389/fgene.2024.1336427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Accepted: 02/23/2024] [Indexed: 03/26/2024] Open
Abstract
Historical vicariance events, linked to the existence of stable physical barriers to gene flow, generate concordant genetic breaks in co-distributed species while stochastic processes (e.g., costal uplift) could cause species-specific genetic breaks as a result of local strong demographic bottlenecks or extinction. In Chile, previous studies show that the area of the 30°S-33°S could correspond to a stable barrier to gene flow that have affected the genetic structure of various algae and marine invertebrates. Here we sequenced two organellar genes (COI and rbcL) in four taxonomically accepted co-distributed red seaweeds species characterized by a low dispersal potential: Mazzaella laminarioides, M. membranacea, Asterfilopsis disciplinalis, and Ahnfeltiopsis vermicularis. Our results revealed the existence of ten strongly differentiated linages in the taxa studied. Strong genetic breaks, concordant in both space and time (divergence estimated to have occurred some 2.9-12.4 million years ago), were observed between taxa distributed across the 33°S. Conversely, in the Central/South part of the Chilean coast, the localization of the genetic breaks/sub-structure observed varied widely (36°S, 38°S, 39°S, and 40°S). These results suggest that a major historical vicariance event has modeled the genetic structure of several Chilean marine organisms in the north of the Chilean coast during the mid-Miocene, while more recent stochastic events and genetic drift could be the driving forces of genetic divergence/structuration in the central-southern part of the coast.
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Affiliation(s)
- Oscar R. Huanel
- Núcleo Milenio MASH, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
- IRL 3614 Evolutionary Biology and Ecology of Algae, Centre National de la Recherche Scientifique (CNRS), Sorbonne Université, Pontificia Universidad Católica de Chile, Universidad Austral de Chile, Station Biologique, Roscoff, France
- GEMA Center for Genomics, Ecology and Environment, Universidad Mayor, Santiago, Chile
| | - Alejandro E. Montecinos
- Instituto de Ciencias Ambientales y Evolutivas, Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile
| | - Francisco Sepúlveda-Espinoza
- Instituto de Ciencias Ambientales y Evolutivas, Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile
| | - Marie-Laure Guillemin
- IRL 3614 Evolutionary Biology and Ecology of Algae, Centre National de la Recherche Scientifique (CNRS), Sorbonne Université, Pontificia Universidad Católica de Chile, Universidad Austral de Chile, Station Biologique, Roscoff, France
- Instituto de Ciencias Ambientales y Evolutivas, Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile
- Núcleo Milenio MASH, Instituto de Ciencias Ambientales y Evolutivas, Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile
- Centro FONDAP de Investigación de Ecosistemas Marinos de Altas Latitudes (IDEAL), Valdivia, Chile
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Briones C, Nuñez JJ, Pérez M, Garrido O, Campos B, Godoy K, Hartley R, Oyarzún PA, Guiñez R. Linking Acrosome Size and Genetic Divergence in an Inter-Oceanic Mussel from the Pacific and Atlantic Coasts: A Case of Incipient Speciation? Animals (Basel) 2024; 14:674. [PMID: 38473058 DOI: 10.3390/ani14050674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 02/14/2024] [Accepted: 02/19/2024] [Indexed: 03/14/2024] Open
Abstract
In recent years, advances in analyses of the sperm morphology and genetics of Perumytilus purpuratus have allowed to two evolutionary scenarios for this mussel to be suggested: (1) the scenario of cryptic species and (2) the scenario of incipient or in progress speciation. For a better understanding of the evolutionary history of P. purpuratus, we performed extensive sampling along a latitudinal gradient of ca. 7180 km of coastline-from the Southern Pacific Ocean to the Atlantic Ocean-and we delved deeper into the sperm morphology of P. purpuratus, exploring its association with the phylogeny and population genetics to determine whether the variability in sperm traits between the northern and southern regions was a signal of cryptic or incipient species. Overall, our results showed that sperm sizes were strongly correlated with the genetic structure in males of P. purpuratus. We identified at 37° S on the Pacific coast a coincident break of both sperm size and genetic disruption that can be explained by historical events and postglacial recolonization as causal phenomena for the observed divergences. Furthermore, evidence of genetic admixture between lineages was found at 38° S, suggesting the presence of an introgressive hybridization zone and incomplete reproductive isolation in an in fraganti or incipient speciation process.
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Affiliation(s)
- Carolina Briones
- Instituto de Ciencias Naturales Alexander von Humbodt, Facultad de Ciencias del Mar y de Recursos Biológicos, Universidad de Antofagasta, Angamos 601, Antofagasta 1270300, Chile
| | - José J Nuñez
- Instituto de Ciencias Marinas y Limnológicas, Facultad de Ciencias, Universidad Austral de Chile, Casilla 567, Valdivia 5090000, Chile
| | - Montse Pérez
- AquaCOV, Centro Oceanográfico de Vigo, Instituto Español de Oceanografía, Consejo Superior de Investigaciones Científicas (IEO, CSIC), 36390 Vigo, Spain
| | - Orlando Garrido
- Instituto de Ciencias Marinas y Limnológicas, Facultad de Ciencias, Universidad Austral de Chile, Casilla 567, Valdivia 5090000, Chile
| | | | - Karina Godoy
- Núcleo Científico y Tecnológico de Biorecursos (BIOREN), Universidad de La Frontera, Temuco 4811230, Chile
| | - Ricardo Hartley
- Instituto de Investigación y Postgrado, Facultad de Medicina y Ciencias de la Salud, Universidad Central de Chile, Santiago 8330507, Chile
| | - Pablo A Oyarzún
- Centro de Investigación Marina Quintay (CIMARQ), Universidad Andrés Bello, Quintay 2340000, Chile
| | - Ricardo Guiñez
- Instituto de Ciencias Naturales Alexander von Humbodt, Facultad de Ciencias del Mar y de Recursos Biológicos, Universidad de Antofagasta, Angamos 601, Antofagasta 1270300, Chile
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Aldea C, Hernández C, Novoa L, Olivera F, Haeger C, Bello N. Biotopes of the intertidal zone in Clarence Island (south of the Strait of Magellan). Biodivers Data J 2023; 11:e105726. [PMID: 37455699 PMCID: PMC10339110 DOI: 10.3897/bdj.11.e105726] [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] [Received: 04/29/2023] [Accepted: 06/25/2023] [Indexed: 07/18/2023] Open
Abstract
Background The characteristics of the Strait of Magellan promote the formation of unique environments, with diverse habitats and marine organisms. This fragmentation of the landscape generates diverse little-explored ecological associations, especially in the zone of sub-Antarctic islands of the Tierra del Fuego archipelago. One way to address this lack of knowledge is through the biotope characterization methodology, with ecological units composed of the habitat and the communities associated with these environments, obtaining data and information on the dominant and incidental taxonomic groups. This is a good research model to conduct baseline studies in coastal benthic marine environments. New information A data set in Darwin Core standard is presented of the species that make up the intertidal biotopes of Clarence Island (Tierra del Fuego Archipelago, south of the Strait of Magellan). This includes 50 identified species and the specific coordinates for each sampled location, with a total of 1400 georeferenced records. Mollusks were the most diverse taxon with 21 species, followed by algae (14 species). Sessile organisms such as the barnacles Elminiuskingii and Austromegabalanuspsittacus predominate in these ecosystems, followed by bivalve mollusks such as Choromytiluschorus and Mytiluschilensis, which together with Nacellamagellanica and the alga Hildenbrandia sp. make up more than 50% of the total records. The inclusion of biotope patterns in this study complements the information on benthic marine flora and fauna in the intertidal zone, including new records for the coast in the Clarence Island area, which is within the boundary of the Kawésqar National Park.
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Affiliation(s)
- Cristian Aldea
- Departamento de Ciencias y Recursos Naturales, Universidad de Magallanes, Punta Arenas, ChileDepartamento de Ciencias y Recursos Naturales, Universidad de MagallanesPunta ArenasChile
- Centro de Investigación Gaia-Antártica, Universidad de Magallanes, Punta Arenas, ChileCentro de Investigación Gaia-Antártica, Universidad de MagallanesPunta ArenasChile
| | - Cristina Hernández
- Departamento de Ciencias y Recursos Naturales, Universidad de Magallanes, Punta Arenas, ChileDepartamento de Ciencias y Recursos Naturales, Universidad de MagallanesPunta ArenasChile
| | - Leslie Novoa
- Departamento de Ciencias y Recursos Naturales, Universidad de Magallanes, Punta Arenas, ChileDepartamento de Ciencias y Recursos Naturales, Universidad de MagallanesPunta ArenasChile
| | - Francisco Olivera
- GEOGAMA, Empresa de Base Científico Tecnológica, Puerto Aysén, ChileGEOGAMA, Empresa de Base Científico TecnológicaPuerto AysénChile
| | - Christian Haeger
- GEOGAMA, Empresa de Base Científico Tecnológica, Puerto Aysén, ChileGEOGAMA, Empresa de Base Científico TecnológicaPuerto AysénChile
| | - Nadja Bello
- GEOGAMA, Empresa de Base Científico Tecnológica, Puerto Aysén, ChileGEOGAMA, Empresa de Base Científico TecnológicaPuerto AysénChile
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Boo GH, Bottalico A, Le Gall L, Yoon HS. Genetic Diversity and Phylogeography of a Turf-Forming Cosmopolitan Marine Alga, Gelidium crinale (Gelidiales, Rhodo-Phyta). Int J Mol Sci 2023; 24:ijms24065263. [PMID: 36982334 PMCID: PMC10049384 DOI: 10.3390/ijms24065263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 03/03/2023] [Accepted: 03/07/2023] [Indexed: 03/12/2023] Open
Abstract
Cosmopolitan species are rare in red algae, which have a low-dispersal capacity unless they are dispersed by human-mediated introductions. Gelidium crinale, a turf-forming red alga, has a widespread distribution in tropical and temperate waters. To decipher the genetic diversity and phylogeography of G. crinale, we analyzed mitochondrial COI-5P and plastid rbcL sequences from collections in the Atlantic, Indian, and Pacific Oceans. Phylogenies of both markers statistically supported the monophyly of G. crinale, with a close relationship to G. americanum and G. calidum from the Western Atlantic. Based on the molecular analysis from these materials, Pterocladia heteroplatos from India is here merged with G. crinale. Phylogeny and TCS networks of COI-5P haplotypes revealed a geographic structure of five groups: (i) Atlantic-Mediterranean, (ii) Ionian, (iii) Asian, (iv) Adriatic-Ionian, and (v) Australasia-India-Tanzania-Easter Island. The most common ancestor of G. crinale likely diverged during the Pleistocene. The Bayesian Skyline Plots suggested the pre-LGM population expansion. Based on geographical structure, lineage-specific private haplotypes, the absence of shared haplotypes between lineages, and AMOVA, we propose that the cosmopolitan distribution of G. crinale has been shaped by Pleistocene relicts. The survival of the turf species under environmental stresses is briefly discussed.
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Affiliation(s)
- Ga Hun Boo
- Department of Biological Sciences, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Antonella Bottalico
- Department of Biosciences, Biotechnologies and Environment, University of Bari “A. Moro”, Via E. Orabona 4, 70125 Bari, Italy
| | - Line Le Gall
- Institut de Systématique, Evolution, Biodiversité (ISYEB), Muséum National d’Histoire Naturelle, CNRS, Sorbonne Université, EPHE, 75005 Paris, France
| | - Hwan Su Yoon
- Department of Biological Sciences, Sungkyunkwan University, Suwon 16419, Republic of Korea
- Correspondence:
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Pinochet R, Pardo LM, Cárdenas L. Assessing diversity of King Crab
Lithodes
spp. in the south‐eastern pacific using phylogeny and molecular species delimitation methods. Ecol Evol 2022; 12:e9143. [PMID: 35923941 PMCID: PMC9339758 DOI: 10.1002/ece3.9143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 06/28/2022] [Accepted: 07/01/2022] [Indexed: 11/08/2022] Open
Abstract
The purpose of this study was to test the hypothesis that the genetic diversity of commercially significant species of King Crabs (Lithodes spp.) along the south‐eastern Pacific (SEP) comprises different independent evolutionary units (IEUs) with spatially isolated distribution. Nine localities from inner and open waters along the SEP Chilean coast (39°S‐55°S) were sampled. We analyzed sequences from 173 individuals for the mitochondrial gene Cytochrome oxidase I (COX‐I), 151 individuals for the Internal Transcribed Spacer 1 (ITS) and 135 for the structural ribosomal RNA (28S). Genetic delimitation was performed through three analytical methods: ABGD, GMYC, and its Bayesian implementation, bGMYC. Bayesian phylogenetic analyses and haplotype networks were also performed. Divergence time between clades was assessed for the COX‐I marker and estimated from known evolutionary rates for this marker in other crustacean species and fossil calibration from other Anomuran species. Delimitation analyses, phylogenetic analyses, and mitochondrial haplotype networks suggested the presence of two deeply divergent mitochondrial lineages of Lithodes in the SEP, referred to as Clade1 and Clade 2. Nuclear markers showed low phylogenetic resolution and therefore were unsuitable for molecular species delimitation. Divergence time analysis of the mitochondrial lineages suggests a separation between Clades of approximately 2.3 Mya. The divergence time obtained suggested that Pliocene glaciations and deglaciations cycles could be involved in hybridization events between Lithodes IEUs at southern tip of South American coasts. The different frequencies of Lithodes haplotypes in inner and open water environments along SEP coasts could be explained by events such as the last glacial maximum or by differences in the adaptation of each clade to different environments. These findings support the necessity of evaluating the taxonomic status of Lithodes individuals found along SEP coasts under an integrative taxonomy approach or through markers with other evolution rates than those already used.
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Affiliation(s)
- Ramona Pinochet
- Programa de Doctorado en Biología Marina, Facultad de Ciencias Universidad Austral de Chile Valdivia Chile
- Centro de Investigación de Dinámica de Ecosistemas Marinos de Altas Latitudes (IDEAL) Valdivia Chile
| | - Luis Miguel Pardo
- Centro de Investigación de Dinámica de Ecosistemas Marinos de Altas Latitudes (IDEAL) Valdivia Chile
- Instituto de Ciencias Marinas y Limnológicas, Facultad de Ciencias Universidad Austral de Chile Valdivia Chile
| | - Leyla Cárdenas
- Centro de Investigación de Dinámica de Ecosistemas Marinos de Altas Latitudes (IDEAL) Valdivia Chile
- Instituto de Ciencias ambientales y evolutivas, Facultad de Ciencias Universidad Austral de Chile Valdivia Chile
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7
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Fica-Rojas E, Catalán AM, Broitman BR, Pérez-Matus A, Valdivia N. Independent Effects of Species Removal and Asynchrony on Invariability of an Intertidal Rocky Shore Community. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.866950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Ecological stability depends on interactions between different levels of biological organization. The insurance effects occur when increasing species diversity leads to more temporally invariable (i.e., more stable) community-level properties, due in part to asynchronous population-level fluctuations. While the study of insurance effects has received considerable attention, the role of dominant species that contribute with particular functional traits across different level of organizations is less understood. Using a field-based manipulative experiment, we investigated how species richness and different types of parameters at the population level, such as the invariability of dominants, population invariability, and population asynchrony, influence the community invariability. The experiment involved the repetitive removal of the canopy forming alga Mazzaella laminarioides (hereafter “Mazzaella”) during 32 months in two rocky intertidal sites of northern-central Chile. We predicted that the invariability of dominants enhances community invariability, that the effect of multispecies population-level parameters on community invariability are dependent on species richness, and that subdominant algae are unable to fully compensate the loss of canopies of the dominant species. Biomass of algae and mobile invertebrates was quantified over time. We observed independent effects of Mazzaella removal and community-wide asynchrony on community invariability. While canopy removal reduced community invariability, population asynchrony boosted community invariability regardless of the presence of canopies. In addition, filamentous and foliose algae were unable to compensate the loss of biomass triggered by the experimental removal of Mazzaella. Canopy removal led to a severe decrement in the biomass of macrograzers, while, at the same time, increased the biomass of mesograzers. Asynchrony stemmed from compensatory trophic responses of mesograzers to increased abundances of opportunistic algae. Thus, further work on consumer-resource interactions will improve our understanding of the links between population- and community-level aspects of stability.
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Saenz‐Agudelo P, Peluso L, Nespolo R, Broitman BR, Haye PA, Lardies MA. Population genomic analyses reveal hybridization and marked differences in genetic structure of
Scurria
limpet sister species with parapatric distributions across the South Eastern Pacific. Ecol Evol 2022; 12:e8888. [PMID: 35571762 PMCID: PMC9078047 DOI: 10.1002/ece3.8888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Revised: 03/30/2022] [Accepted: 04/08/2022] [Indexed: 11/08/2022] Open
Affiliation(s)
- Pablo Saenz‐Agudelo
- Instituto de Ciencias Ambientales y Evolutivas Universidad Austral de Chile Valdivia Chile
- ANID‐ Millennium Science Initiative Nucleus (NUTME) Las Cruces Chile
| | - Lívia Peluso
- Instituto de Ciencias Ambientales y Evolutivas Universidad Austral de Chile Valdivia Chile
- Doctorado en Ciencias Mención Ecología y Evolución Escuela de Graduados Facultad de Ciencias Universidad Austral de Chile Valdivia Chile
| | - Roberto Nespolo
- Instituto de Ciencias Ambientales y Evolutivas Universidad Austral de Chile Valdivia Chile
- ANID‐ Millennium Science Initiative Nucleus (LiLi) Valdivia Chile
- Center for Applied Ecology and Sustainability (CAPES) Santiago Chile
- Millennium Institute for Integrative Biology (iBio) Santiago Chile
| | - Bernardo R. Broitman
- Departamento de Ciencias Facultad de Artes Liberales Universidad Adolfo Ibañez Santiago Chile
- ANID‐ Millennium Science Initiative Nucleus UPWELL Santiago Chile
- Instituto Milenio en Socio‐Ecología Costera (SECOS) Santiago Chile
| | - Pilar A. Haye
- Instituto Milenio en Socio‐Ecología Costera (SECOS) Santiago Chile
- Departamento de Biología Marina Universidad Católica del Norte Coquimbo Chile
| | - Marco A. Lardies
- Departamento de Ciencias Facultad de Artes Liberales Universidad Adolfo Ibañez Santiago Chile
- Instituto Milenio en Socio‐Ecología Costera (SECOS) Santiago Chile
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9
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Tonicelli GA, Croce ME, Díaz-Tapia P, Fredericq S, Freshwater DW, Gauna MC, Parodi ER, Verbruggen H, Hommersand MH. Meridionella gen. nov., a New Genus of Cystocloniaceae (Gigartinales, Rhodophyta) from the Southern Hemisphere, Including M. obtusangula comb. nov. and M. antarctica sp. nov. JOURNAL OF PHYCOLOGY 2021; 57:797-816. [PMID: 33450046 DOI: 10.1111/jpy.13127] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 10/28/2020] [Accepted: 10/29/2020] [Indexed: 06/12/2023]
Abstract
The classification of Cystoclonium obtusangulum has been questioned since the species was first described by Hooker and Harvey as Gracilaria? obtusangula. The objective of this study was to provide the first comprehensive taxonomic analysis of Cystoclonium obtusangulum, based on DNA sequences coupled with morphological observations made on syntype specimens and new collections. Sequence divergences of rbcL, UPA, and COI-5P, and maximum-likelihood phylogenies for rbcL and 18S demonstrated that specimens identified as Cystoclonium obtusangulum represent a clade of two distinct species that are distantly related to the generitype Cystoclonium purpureum. A new genus, Meridionella gen. nov., is proposed for this clade. The two species placed in this new genus were morphologically indistinguishable cryptic species, but have disjunct distributions, with Meridionella obtusangula comb. nov. found from temperate to cold coasts of South America and the Falkland Islands and Meridionella antarctica sp. nov., occurring in Antarctic waters. Vegetative and reproductive characters of Meridionella gen. nov. are described, and implications of our results for the biogeography of the family Cystocloniaceae are discussed.
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Affiliation(s)
- Gina A Tonicelli
- Instituto Argentino de Oceanografía, CONICET-UNS, Camino La carrindanga km 7.5, Bahía Blanca, 8000, Argentina
- Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur, San Juan 670, Bahía Blanca, 8000, Argentina
| | - Maria Emilia Croce
- Instituto Argentino de Oceanografía, CONICET-UNS, Camino La carrindanga km 7.5, Bahía Blanca, 8000, Argentina
- Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur, San Juan 670, Bahía Blanca, 8000, Argentina
| | - Pilar Díaz-Tapia
- Coastal Biology Research Group, Faculty of Sciences and Centre for Advanced Scientific Research (CICA), University of A Coruña, 15071, A Coruña, Spain
- Instituto Español de Oceanografía (IEO), Centro Oceanográfico de A Coruña, Apdo, 130, 15080, A Coruña, Spain
| | - Suzanne Fredericq
- Department of Biology, University of Louisiana at Lafayette, Lafayette, Louisiana, 70504-3602, USA
| | - David Wilson Freshwater
- Center for Marine Science, University of North Carolina at Wilmington, 5600 Marvin Moss Lane, Wilmington, North Carolina, 28409, USA
| | - Maria Cecilia Gauna
- Instituto Argentino de Oceanografía, CONICET-UNS, Camino La carrindanga km 7.5, Bahía Blanca, 8000, Argentina
- Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur, San Juan 670, Bahía Blanca, 8000, Argentina
| | - Elisa R Parodi
- Instituto Argentino de Oceanografía, CONICET-UNS, Camino La carrindanga km 7.5, Bahía Blanca, 8000, Argentina
- Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur, San Juan 670, Bahía Blanca, 8000, Argentina
| | - Heroen Verbruggen
- School of BioSciences, University of Melbourne, Melbourne, Victoria, 3010, Australia
| | - Max H Hommersand
- Department of Biology, University of North Carolina at Chapel Hill, Coker Hall, Chapel Hill, North Carolina, 27599-3280, USA
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10
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Huanel OR, Nelson WA, Robitzch V, Mauger S, Faugeron S, Preuss M, Zuccarello GC, Guillemin ML. Comparative phylogeography of two Agarophyton species in the New Zealand archipelago. JOURNAL OF PHYCOLOGY 2020; 56:1575-1590. [PMID: 32609871 DOI: 10.1111/jpy.13046] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2020] [Accepted: 06/23/2020] [Indexed: 06/11/2023]
Abstract
Molecular studies have reported the coexistence of two species of Agarophyton in New Zealand: the newly described A.transtasmanicum with an apparently restricted distribution to some sites in the North Island, and the more widespread A.chilense. Here, we compared the distribution, genetic diversity, and structure of both Agarophyton species throughout the archipelago using sequences of the nuclear Internal Transcribed Spacer 2 (ITS2) marker. Agarophyton chilense's distribution was continuous and extensive along the North and South Islands, Stewart Island, and Chatham Island, and the genetic clusters were mostly concordant with boundaries between biogeographic regions. In contrast, specimens of A.transtasmanicum were collected in four sites broadly distributed in both the North and South Islands, with no clear spatial structure of the genetic diversity. Populations, where the species co-occurred, tended to display similar levels in genetic diversity for the two species. Demographic inferences supported a postglacial demographic expansion for two A.chilense genetic clusters, one present in the South Island and the eastern coast of the North Island, and the other present in northern South Island. A third genetic cluster located on the western coast of the North Island had a signature of long-term demographic stability. For A.transtasmanicum, the skyline plot also suggested a postglacial demographic expansion. Last, we developed a new molecular tool to quickly and easily distinguish between the two Agarophyton species, which could be used to ease future fine-scale population studies, especially in areas where the two species coexist.
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Affiliation(s)
- Oscar R Huanel
- Departamento de Ecología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Casilla 114-D, Santiago, Chile
- CNRS, Sorbonne Université, UMI 3614, Evolutionary Biology and Ecology of Algae, Station Biologique de Roscoff, CS 90074, Place G. Tessier, 296888, Roscoff, France
| | - Wendy A Nelson
- National Institute of Water and Atmospheric Research, Wellington, 6021, New Zealand
- School of Biological Sciences, University of Auckland, Auckland, 1142, New Zealand
| | - Vanessa Robitzch
- Instituto de Ciencias Ambientales y Evolutivas, Facultad de Ciencias, Universidad Austral de Chile, Casilla 567, Valdivia, Chile
| | - Stéphane Mauger
- CNRS, Sorbonne Université, UMI 3614, Evolutionary Biology and Ecology of Algae, Station Biologique de Roscoff, CS 90074, Place G. Tessier, 296888, Roscoff, France
| | - Sylvain Faugeron
- Departamento de Ecología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Casilla 114-D, Santiago, Chile
- CNRS, Sorbonne Université, UMI 3614, Evolutionary Biology and Ecology of Algae, Station Biologique de Roscoff, CS 90074, Place G. Tessier, 296888, Roscoff, France
| | - Maren Preuss
- School of Biological Sciences, Victoria University of Wellington, Wellington, 6140, New Zealand
| | - Giuseppe C Zuccarello
- School of Biological Sciences, Victoria University of Wellington, Wellington, 6140, New Zealand
| | - Marie-Laure Guillemin
- CNRS, Sorbonne Université, UMI 3614, Evolutionary Biology and Ecology of Algae, Station Biologique de Roscoff, CS 90074, Place G. Tessier, 296888, Roscoff, France
- Instituto de Ciencias Ambientales y Evolutivas, Facultad de Ciencias, Universidad Austral de Chile, Casilla 567, Valdivia, Chile
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11
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Márquez F, Trovant B, Van der Molen S, Sepúlveda RD, Doña J, Johnson KP, Vierna J. Two evolutionary units on the South American razor clam Ensis macha (Bivalvia: Pharidae): genetic and morphometric evidence. ORG DIVERS EVOL 2020. [DOI: 10.1007/s13127-020-00441-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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12
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Segovia NI, González-Wevar CA, Haye PA. Signatures of local adaptation in the spatial genetic structure of the ascidian Pyura chilensis along the southeast Pacific coast. Sci Rep 2020; 10:14098. [PMID: 32839518 PMCID: PMC7445245 DOI: 10.1038/s41598-020-70798-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Accepted: 07/21/2020] [Indexed: 11/25/2022] Open
Abstract
The highly heterogeneous Humboldt Current System (HCS) and the 30°S transition zone on the southeast Pacific coast, represent an ideal scenario to test the influence of the environment on the spatial genomic structure in marine near-shore benthic organisms. In this study, we used seascape genomic tools to evaluate the genetic structure of the commercially important ascidian Pyura chilensis, a species that exhibits a low larval transport potential but high anthropogenic dispersal. A recent study in this species recorded significant genetic differentiation across a transition zone around 30°S in putatively adaptive SNPs, but not in neutral ones, suggesting an important role of environmental heterogeneity in driving genetic structure. Here, we aim to understand genomic-oceanographic associations in P. chilensis along the Southeastern Pacific coast using two combined seascape genomic approaches. Using 149 individuals from five locations along the HCS, a total of 2,902 SNPs were obtained by Genotyping-By-Sequencing, of which 29–585 were putatively adaptive loci, depending on the method used for detection. In adaptive loci, spatial genetic structure was better correlated with environmental differences along the study area (mainly to Sea Surface Temperature, upwelling-associated variables and productivity) than to the geographic distance between sites. Additionally, results consistently showed the presence of two groups, located north and south of 30°S, which suggest that local adaptation processes seem to allow the maintenance of genomic differentiation and the spatial genomic structure of the species across the 30°S biogeographic transition zone of the Humboldt Current System, overriding the homogenizing effects of gene flow.
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Affiliation(s)
- Nicolás I Segovia
- Departamento de Biología Marina, Facultad de Ciencias del Mar, Universidad Católica del Norte, Coquimbo, Chile.,Departamento de Ciencias Ecológicas, Facultad de Ciencias, Instituto de Ecología Y Biodiversidad IEB, Universidad de Chile, Santiago, Chile
| | - Claudio A González-Wevar
- Departamento de Ciencias Ecológicas, Facultad de Ciencias, Instituto de Ecología Y Biodiversidad IEB, Universidad de Chile, Santiago, Chile.,Instituto de Ciencias Marinas Y Limnológicas (ICML), Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile.,Centro FONDAP de Investigaciones en Dinámica de Ecosistemas de Altas Latitudes (IDEAL), Universidad Austral de Chile, Valdivia, Chile
| | - Pilar A Haye
- Departamento de Biología Marina, Facultad de Ciencias del Mar, Universidad Católica del Norte, Coquimbo, Chile.
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13
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Aguilera MA, Valdivia N, Broitman BR, Jenkins SR, Navarrete SA. Novel co-occurrence of functionally redundant consumers induced by range expansion alters community structure. Ecology 2020; 101:e03150. [PMID: 32730670 DOI: 10.1002/ecy.3150] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 06/04/2020] [Accepted: 06/19/2020] [Indexed: 11/06/2022]
Abstract
Ongoing climate change is shifting the geographic distributions of some species, potentially imposing rapid changes in local community structure and ecosystem functioning. Besides changes in population-level interspecific interactions, such range shifts may also cause changes in functional structure within the host assemblages, which can result in losses or gains in ecosystem functions. Because consumer-resource dynamics are central to community regulation, functional reorganization driven by introduction of new consumer species can have large consequences on ecosystem functions. Here we experimentally examine the extent to which the recent poleward range expansion of the intertidal grazer limpet Scurria viridula along the coast of Chile has altered the role of the resident congeneric limpet S. zebrina, and whether the net collective impacts, and functional structure, of the entire herbivore guild have been modified by the introduction of this new member. We examined the functional role of Scurria species in controlling ephemeral algal cover, bare rock availability, and species richness and diversity, and compared the effects in the region of range overlap against their respective "native" abutted ranges. Experiments showed depression of per capita effects of the range-expanded species within the region of overlap, suggesting environmental conditions negatively affect individual performance. In contrast, effects of S. zebrina were commonly invariant at its range edge. When comparing single species versus polycultures, effects on bare rock cover were altered by the presence of the other Scurria species, suggesting competition between Scurria species. Importantly, although the magnitude of S. viridula effects at the range overlap was reduced, its addition to the herbivore guild seems to complement and intensify the role of the guild in reducing green algal cover, species richness and increasing bare space provision. Our study thus highlights that range expansion of an herbivore can modify the functional guild structure in the recipient community. It also highlights the complexity of predicting how functional structure may change in the face of natural or human-induced range expansions. There is a need for more field-based examination of regional functional compensation, complementarity, or inhibition before we can construct a conceptual framework to anticipate the consequences of species range expansions.
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Affiliation(s)
- Moisés A Aguilera
- Departamento de Biología Marina, Facultad de Ciencias del Mar, Universidad Católica del Norte, Larrondo, 1281, Coquimbo, Chile.,Centro de Estudios Avanzados en Zonas Áridas (CEAZA), Ossandón 877, Coquimbo, Chile
| | - Nelson Valdivia
- Instituto de Ciencias Marinas y Limnológicas, Facultad de Ciencias, Universidad Austral de Chile, Campus Isla Teja, Valdivia, 5110236, Chile.,Centro FONDAP de Investigación de Dinámicas de Ecosistemas Marinos de Altas Latitudes (IDEAL), Chile
| | - Bernardo R Broitman
- Departamento de Ciencias Biológicas, Facultad de Artes Liberales, Universidad Adolfo Ibáñez, Viña de Mar, Chile
| | - Stuart R Jenkins
- School of Ocean Sciences, Bangor University, Menai Bridge, Anglesey, LL59 5AB, UK
| | - Sergio A Navarrete
- Estación Costera de Investigaciones Marinas, Las Cruces, Center for Applied Ecology and Sustainability (CAPES), Pontificia Universidad Católica de Chile, Casilla 114-D, Santiago, Chile
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14
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Lipidic profile of sub-Antarctic seaweed Mazzaella laminarioides (Gigartinales, Rhodophyta) in distinct developmental phases and cell cytotoxicity in bladder cancer. ALGAL RES 2020. [DOI: 10.1016/j.algal.2020.101936] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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15
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Boo GH, Qiu YX, Kim JY, Ang PO, Bosch S, De Clerck O, He P, Higa A, Huang B, Kogame K, Liu SL, van Nguyen T, Suda S, Terada R, Miller KA, Boo SM. Contrasting patterns of genetic structure and phylogeography in the marine agarophytes Gelidiophycus divaricatus and G. freshwateri (Gelidiales, Rhodophyta) from East Asia. JOURNAL OF PHYCOLOGY 2019; 55:1319-1334. [PMID: 31390066 DOI: 10.1111/jpy.12910] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 07/19/2019] [Indexed: 06/10/2023]
Abstract
The evolutionary and population demographic history of marine red algae in East Asia is poorly understood. Here, we reconstructed the phylogeographies of two upper intertidal species endemic to East Asia, Gelidiophycus divaricatus and G. freshwateri. Phylogenetic and phylogeographic inferences of 393 mitochondrial cox1, 128 plastid rbcL, and 342 nuclear ITS2 sequences were complemented with ecological niche models. Gelidiophycus divaricatus, a southern species adapted to warm water, is characterized by a high genetic diversity and a strong geographical population structure, characteristic of stable population sizes and sudden reduction to recent expansion. In contrast, G. freshwateri, a northern species adapted to cold temperate conditions, is genetically relatively homogeneous with a shallow population structure resulting from steady population growth and recent equilibrium. The overlap zone of the two species roughly matches summer and winter isotherms, indicating that surface seawater temperature is a key feature influencing species range. Unidirectional genetic introgression was detected at two sites on Jeju Island where G. divaricatus was rare while G. freshwateri was common, suggesting the occurrence of asymmetric natural hybrids, a rarely reported event for rhodophytes. Our results illustrate that Quaternary climate oscillations have left strong imprints on the current day genetic structure and highlight the importance of seawater temperature and sea level change in driving speciation in upper intertidal seaweed species.
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Affiliation(s)
- Ga Hun Boo
- University Herbarium, University of California, 1001 Valley Life Sciences Building #2465, Berkeley, California, 94720, USA
- Department of Biology, Chungnam National University, Daejeon, 34134, Korea
| | - Ying-Xiong Qiu
- Key Laboratory of Conservation Biology for Endangered Wildlife of the Ministry of Education, and College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Jung Yeon Kim
- Department of Biology, Chungnam National University, Daejeon, 34134, Korea
| | - Put O Ang
- Marine Science Laboratory, The Chinese University of Hong Kong, Shatin N.T, Hong Kong SAR, China
| | - Samuel Bosch
- Phycology Research Group and Center for Molecular Phylogenetics and Evolution, Ghent University, Krijgslaan 281 (S8), 9000, Gent, Belgium
| | - Olivier De Clerck
- Phycology Research Group and Center for Molecular Phylogenetics and Evolution, Ghent University, Krijgslaan 281 (S8), 9000, Gent, Belgium
| | - Peimin He
- College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, 201306, China
| | - Atsushi Higa
- Okinawa Environmental Analysis Center Co. Ltd, 3-7-24 Maehara, Ginowan, Okinawa, 901-2215, Japan
| | - Bangqin Huang
- Key Laboratory of Coastal Ecology and Environmental Studies, Xiamen University, Fujian, China
| | - Kazuhiro Kogame
- Department of Natural History Sciences, Faculty of Science, Hokkaido University, Sapporo, 060-0810, Japan
| | - Shao-Lun Liu
- Department of Life Science, Tunghai University, Taichung, 40704, Taiwan
| | - Tu van Nguyen
- Department of Ecology, Institute of Tropical Biology, Vietnam Academy of Science and Technology, 85 Tran Quoc Toan, District 3, Ho Chi Minh City, Vietnam
| | - Shoichiro Suda
- Department of Chemistry, Biology & Marine Science, Faculty of Science, University of the Ryukyus, Okinawa, 903-0213, Japan
| | - Ryuta Terada
- United Graduate School of Agricultural Sciences, Kagoshima University, Korimoto 1-21-24, Kagoshima, 890-0065, Japan
| | - Kathy Ann Miller
- University Herbarium, University of California, 1001 Valley Life Sciences Building #2465, Berkeley, California, 94720, USA
| | - Sung Min Boo
- Department of Biology, Chungnam National University, Daejeon, 34134, Korea
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16
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Ayres-Ostrock LM, Valero M, Mauger S, Oliveira MC, Plastino EM, Guillemin ML, Destombe C. Dual influence of terrestrial and marine historical processes on the phylogeography of the Brazilian intertidal red alga Gracilaria caudata. JOURNAL OF PHYCOLOGY 2019; 55:1096-1114. [PMID: 31206679 DOI: 10.1111/jpy.12892] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Accepted: 05/24/2019] [Indexed: 06/09/2023]
Abstract
In this study, we explored how past terrestrial and marine climate changes have interacted to shape the phylogeographic patterns of the intertidal red seaweed Gracilaria caudata, an economically important species exploited for agar production in the Brazilian north-east. Seven sites were sampled along the north-east tropical and south-east sub-tropical Brazilian coast. The genetic diversity and structure of G. caudata was inferred using a combination of mitochondrial (COI and cox2-3), chloroplast (rbcL) and 15 nuclear microsatellite markers. A remarkable congruence between nuclear, mitochondrial and chloroplast data revealed clear separation between the north-east (from 03° S to 08° S) and the south-east (from 20° S to 23° S) coast of Brazil. These two clades differ in their demographic histories, with signatures of recent demographic expansions in the north-east and divergent populations in the south-east, suggesting the maintenance of several refugia during the last glacial maximum due to sea-level rise and fall. The Bahia region (around 12° S) occupies an intermediate position between both clades. Microsatellites and mtDNA markers showed additional levels of genetic structure within each sampled site located south of Bahia. The separation between the two main groups in G. caudata is likely recent, probably occurring during the Quaternary glacial cycles. The genetic breaks are concordant with (i) those separating terrestrial refugia, (ii) major river outflows and (iii) frontiers between tropical and subtropical regions. Taken together with previously published eco-physiological studies that showed differences in the physiological performance of the strains from distinct locations, these results suggest that the divergent clades in G. caudata correspond to distinct ecotypes in the process of incipient speciation and thus should be considered for the management policy of this commercially important species.
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Affiliation(s)
- Lígia M Ayres-Ostrock
- Instituto de Biociências, Universidade de São Paulo, Rua do Matão 277, CEP: 05508-090, São Paulo, SP, Brazil
| | - Myriam Valero
- CNRS, Sorbonne Université, UMI 3614, Evolutionary Biology and Ecology of Algae, Station Biologique de Roscoff, CS 90074, 29688, Roscoff, France
| | - Stéphane Mauger
- CNRS, Sorbonne Université, UMI 3614, Evolutionary Biology and Ecology of Algae, Station Biologique de Roscoff, CS 90074, 29688, Roscoff, France
| | - Mariana C Oliveira
- Instituto de Biociências, Universidade de São Paulo, Rua do Matão 277, CEP: 05508-090, São Paulo, SP, Brazil
| | - Estela M Plastino
- Instituto de Biociências, Universidade de São Paulo, Rua do Matão 277, CEP: 05508-090, São Paulo, SP, Brazil
| | - Marie-Laure Guillemin
- CNRS, Sorbonne Université, UMI 3614, Evolutionary Biology and Ecology of Algae, Station Biologique de Roscoff, CS 90074, 29688, Roscoff, France
- Instituto de Ciencias Ambientales y Evolutivas, Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile
| | - Christophe Destombe
- CNRS, Sorbonne Université, UMI 3614, Evolutionary Biology and Ecology of Algae, Station Biologique de Roscoff, CS 90074, 29688, Roscoff, France
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17
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Morales‐González S, Giles EC, Quesada‐Calderón S, Saenz‐Agudelo P. Fine-scale hierarchical genetic structure and kinship analysis of the ascidian Pyura chilensis in the southeastern Pacific. Ecol Evol 2019; 9:9855-9868. [PMID: 31534699 PMCID: PMC6745665 DOI: 10.1002/ece3.5526] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Revised: 07/12/2019] [Accepted: 07/12/2019] [Indexed: 12/26/2022] Open
Abstract
Studying population structure and genetic diversity at fine spatial scales is key for a better understanding of demographic processes that influence population connectivity. This is particularly important in marine benthic organisms that rely on larval dispersal to maintain connectivity among populations. Here, we report the results of a genetic survey of the ascidian Pyura chilensis from three localities along the southeastern Pacific. This study follows up on a previous report that described a genetic break in this region among localities only 20 km apart. By implementing a hierarchical sampling design at four spatial levels and using ten polymorphic microsatellite markers, we test whether differences in fine-scale population structure explain the previously reported genetic break. We compared genetic spatial autocorrelations, as well as kinship and relatedness distributions within and among localities adjacent to the genetic break. We found no evidence of significant autocorrelation at the scale up to 50 m despite the low dispersal potential of P. chilensis that has been reported in the literature. We also found that the proportion of related individuals in close proximity (<1 km) was higher than the proportion of related individuals further apart. These results were consistent in the three localities. Our results suggest that the spatial distribution of related individuals can be nonrandom at small spatial scales and suggests that dispersal might be occasionally limited in this species or that larval cohorts can disperse in the plankton as clustered groups. Overall, this study sheds light on new aspects of the life of this ascidian as well as confirms the presence of a genetic break at 39°S latitude. Also, our data indicate there is not enough evidence to confirm that this genetic break can be explained by differences in fine-scale genetic patterns among localities.
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Affiliation(s)
- Sarai Morales‐González
- Instituto de Ciencias Ambientales y EvolutivasFacultad de CienciasUniversidad Austral de ChileValdiviaChile
- Magister en Ciencias Mención GenéticaEscuela de GraduadosFacultad de CienciasUniversidad Austral de ChileValdiviaChile
| | - Emily C. Giles
- Instituto de Ciencias Ambientales y EvolutivasFacultad de CienciasUniversidad Austral de ChileValdiviaChile
- Doctorado en Ciencias Mención Ecología y EvoluciónEscuela de GraduadosFacultad de CienciasUniversidad Austral de ChileValdiviaChile
| | - Suany Quesada‐Calderón
- Instituto de Ciencias Ambientales y EvolutivasFacultad de CienciasUniversidad Austral de ChileValdiviaChile
- Doctorado en Ciencias Mención Ecología y EvoluciónEscuela de GraduadosFacultad de CienciasUniversidad Austral de ChileValdiviaChile
| | - Pablo Saenz‐Agudelo
- Instituto de Ciencias Ambientales y EvolutivasFacultad de CienciasUniversidad Austral de ChileValdiviaChile
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18
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Haye PA, Segovia NI, Varela AI, Rojas R, Rivadeneira MM, Thiel M. Genetic and morphological divergence at a biogeographic break in the beach-dwelling brooder Excirolana hirsuticauda Menzies (Crustacea, Peracarida). BMC Evol Biol 2019; 19:118. [PMID: 31185884 PMCID: PMC6560899 DOI: 10.1186/s12862-019-1442-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Accepted: 05/27/2019] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND There is a biogeographic break located at 30°S in the southeast Pacific, in a coastal area of strong environmental discontinuities. Several marine benthic taxa with restricted dispersal have a coincident phylogeographic break at 30°S, indicating that genetic structure is moulded by life history traits that limit gene flow and thereby promote divergence and speciation. In order to evaluate intraspecific divergence at this biogeographic break, we investigated the genetic and morphological variation of the directly developing beach isopod Excirolana hirsuticauda along 1900 km of the southeast Pacific coast, across 30°S. RESULTS The COI sequences and microsatellite data both identified a strong discontinuity between populations of E. hirsuticauda to the north and south of 30°S, and a second weaker phylogeographic break at approximately 35°S. The three genetic groups were evidenced by different past demographic and genetic diversity signatures, and were also clearly distinguished with microsatellite data clustering. The COI sequences established that the genetic divergence of E. hirsuticauda at 30°S started earlier than divergence at 35°. Additionally, the three groups have different past demographic signatures, with probable demographic expansion occurring earlier in the southern group (south of 35°S), associated with Pleistocene interglacial periods. Interestingly, body length, multivariate morphometric analyses, and the morphology of a fertilization-related morphological character in males, the appendix masculina, reinforced the three genetic groups detected with genetic data. CONCLUSIONS The degree of divergence of COI sequences, microsatellite data, and morphology was concordant and showed two geographic areas in which divergence was promoted at differing historical periods. Variation in the appendix masculina of males has probably promoted reproductive isolation. This variation together with gene flow restrictions promoted by life history traits, small body size, oceanographic discontinuities and sandy-beach habitat continuity, likely influenced species divergence at 30°S in the southeast Pacific coast. The degree of genetic and morphological differentiation of populations to the north and south of 30°S suggests that E. hirsuticauda harbours intraspecific divergence consistent with reproductive isolation and an advanced stage of speciation. The speciation process within E. hirsuticauda has been shaped by both restrictions to gene flow and a prezygotic reproductive barrier.
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Affiliation(s)
- Pilar A. Haye
- Departamento de Biología Marina, Facultad de Ciencias del Mar, Universidad Católica del Norte, Larrondo, 1281 Coquimbo, Chile
| | - Nicolás I. Segovia
- Departamento de Biología Marina, Facultad de Ciencias del Mar, Universidad Católica del Norte, Larrondo, 1281 Coquimbo, Chile
| | - Andrea I. Varela
- Departamento de Biología Marina, Facultad de Ciencias del Mar, Universidad Católica del Norte, Larrondo, 1281 Coquimbo, Chile
- Núcleo Milenio de Ecología y Manejo Sustentable de Islas Oceánicas (ESMOI), Universidad Católica del Norte, Coquimbo, Chile
| | - Rodrigo Rojas
- Departamento de Biología Marina, Facultad de Ciencias del Mar, Universidad Católica del Norte, Larrondo, 1281 Coquimbo, Chile
| | - Marcelo M. Rivadeneira
- Departamento de Biología Marina, Facultad de Ciencias del Mar, Universidad Católica del Norte, Larrondo, 1281 Coquimbo, Chile
- Centro de Estudios Avanzados en Zonas Áridas (CEAZA), Coquimbo, Chile
| | - Martin Thiel
- Departamento de Biología Marina, Facultad de Ciencias del Mar, Universidad Católica del Norte, Larrondo, 1281 Coquimbo, Chile
- Núcleo Milenio de Ecología y Manejo Sustentable de Islas Oceánicas (ESMOI), Universidad Católica del Norte, Coquimbo, Chile
- Centro de Estudios Avanzados en Zonas Áridas (CEAZA), Coquimbo, Chile
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19
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Meynard A, Zapata J, Salas N, Betancourtt C, Pérez-Lara G, Castañeda F, Ramírez ME, Bulboa Contador C, Guillemin ML, Contreras-Porcia L. Genetic and morphological differentiation of Porphyra and Pyropia species (Bangiales, Rhodophyta) coexisting in a rocky intertidal in Central Chile. JOURNAL OF PHYCOLOGY 2019; 55:297-313. [PMID: 30570145 DOI: 10.1111/jpy.12829] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Accepted: 08/16/2018] [Indexed: 06/09/2023]
Abstract
A recent molecular taxonomic study along the Chilean coast (18° S-53° S) described 18 candidate species of bladed Bangiales of which only two were formally described. Few studies focused on local genetic and morphological diversity of bladed Bangiales and attempted to determine their intertidal distribution in contrasting habitats, and none were performed in Chile. To delimit intertidal distributions of genetic species, 66 samples of bladed Bangiales were collected at Maitencillo (32° S) in four zones: a rocky platform, a rocky wall, and two boulders zones surrounded by sandy and rocky bottoms, respectively. These samples were identified based on sequences of the mitochondrial COI and chloroplast rbcL markers. We also collected 87 specimens for morphological characterization of the most common species, rapidly assessing their putative species identity using newly developed species-diagnostic (PCR-RFLP) markers. Eight microscopic and two macroscopic morphological traits were measured. We described and named three of four species that predominate in Maitencillo (including Pyropia orbicularis): Pyropia variabilis Zapata, Meynard, Ramírez, Contreras-Porcia, sp. nov., Porphyra luchea Meynard, Ramírez, Contreras-Porcia sp. nov., and Porphyra longissima Meynard, Ramírez, Contreras-Porcia, sp. nov. With the exception of Po. longissima restricted to boulders surrounded by sandy bottom, and a morphotype of Py. variabilis restricted to rocky walls, the other species/morphotypes have overlapping intertidal distributions. Except for Po. longissima, which is clearly differentiated morphologically (longest and thinnest blades), we conclude that morphology is not sufficient to differentiate bladed Bangiales. Our findings underscore the importance of refining our knowledge of intrinsic and environmental determinants on the distribution of bladed Bangiales.
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Affiliation(s)
- Andrés Meynard
- Departamento de Ecología y Biodiversidad, Facultad de Ciencias de la Vida, Universidad Andres Bello, República 440, Santiago, Chile
- Centro de Investigación Marina Quintay (CIMARQ), Facultad de Ciencias de la Vida, Universidad Andres Bello, Quintay, Chile
| | - Javier Zapata
- Departamento de Ecología y Biodiversidad, Facultad de Ciencias de la Vida, Universidad Andres Bello, República 440, Santiago, Chile
- Centro de Investigación Marina Quintay (CIMARQ), Facultad de Ciencias de la Vida, Universidad Andres Bello, Quintay, Chile
| | - Nicolás Salas
- Departamento de Ecología y Biodiversidad, Facultad de Ciencias de la Vida, Universidad Andres Bello, República 440, Santiago, Chile
- Centro de Investigación Marina Quintay (CIMARQ), Facultad de Ciencias de la Vida, Universidad Andres Bello, Quintay, Chile
| | - Claudia Betancourtt
- Departamento de Ecología y Biodiversidad, Facultad de Ciencias de la Vida, Universidad Andres Bello, República 440, Santiago, Chile
- Centro de Investigación Marina Quintay (CIMARQ), Facultad de Ciencias de la Vida, Universidad Andres Bello, Quintay, Chile
| | - Gabriel Pérez-Lara
- Departamento de Ecología y Biodiversidad, Facultad de Ciencias de la Vida, Universidad Andres Bello, República 440, Santiago, Chile
- Centro de Investigación Marina Quintay (CIMARQ), Facultad de Ciencias de la Vida, Universidad Andres Bello, Quintay, Chile
| | - Francisco Castañeda
- Departamento de Ecología y Biodiversidad, Facultad de Ciencias de la Vida, Universidad Andres Bello, República 440, Santiago, Chile
- Centro de Investigación Marina Quintay (CIMARQ), Facultad de Ciencias de la Vida, Universidad Andres Bello, Quintay, Chile
| | - María Eliana Ramírez
- Departamento de Ecología y Biodiversidad, Facultad de Ciencias de la Vida, Universidad Andres Bello, República 440, Santiago, Chile
- Museo Nacional de Historia Natural, Área Botánica, Casilla 787, Santiago, Chile
| | - Cristian Bulboa Contador
- Departamento de Ecología y Biodiversidad, Facultad de Ciencias de la Vida, Universidad Andres Bello, República 440, Santiago, Chile
| | - Marie-Laure Guillemin
- Instituto de Ciencias Ambientales y Evolutivas, Universidad Austral de Chile, Casilla 567, Valdivia, Chile
- CNRS, Sorbonne Universités, UPMC University Paris VI, PUC, UACH, UMI 3614, Evolutionary Biology and Ecology of Algae, Station Biologique de Roscoff, CS 90074, Place G. Teissier, 29680, Roscoff, France
- Centro FONDAP de Investigación en Dinámica de Ecosistemas Marinos de Altas Latitudes (IDEAL), Valdivia, Chile
| | - Loretto Contreras-Porcia
- Departamento de Ecología y Biodiversidad, Facultad de Ciencias de la Vida, Universidad Andres Bello, República 440, Santiago, Chile
- Centro de Investigación Marina Quintay (CIMARQ), Facultad de Ciencias de la Vida, Universidad Andres Bello, Quintay, Chile
- Center of Applied Ecology and Sustainability (CAPES), Santiago, Chile
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Mendes CB, Norenburg JL, Solferini VN, Andrade SCS. Hidden diversity: Phylogeography of genus Ototyphlonemertes Diesing, 1863 (Ototyphlonemertidae: Hoplonemertea) reveals cryptic species and high diversity in Chilean populations. PLoS One 2018; 13:e0195833. [PMID: 29698411 PMCID: PMC5919620 DOI: 10.1371/journal.pone.0195833] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Accepted: 04/01/2018] [Indexed: 11/18/2022] Open
Abstract
Ototyphlonemertes is a cosmopolitan genus of meiofaunal nemerteans. Their morphological characters are insufficient to reliably identify and delimit species. Consequently, some of the species are considered cosmopolitan despite anticipated low dispersion capability of the adults and a short planktonic larval phase. Indeed, recent studies show that some species actually comprise cryptic species, and populations are connected by stochastic events of long-distance dispersion. Based solely on morphological traits, a Lactea and a Pallida morph of Ototyphlonemertes are recognized here from collections at eight and five locations respectively along the Chilean coast. To assess the phylogeographic patterns of their populations, two mitochondrial markers (COI and COX3) of 162 specimens of Lactea and 25 of Pallida were sequenced. Final sequences are 605bp and 362bp for COI and COX3, respectively. Results from phylogenetic and haplotype network analyses suggest that the Lactea morph comprises up to three independent evolutionary units (one with only COX3 sequences). A COI gene tree including other previously published Ototyphlonemertes sequences groups the Chilean Lactea with other Lactea, while the Chilean Pallida is grouped with other Pallida. Different structuring and gene flow patterns found for the four groups support the hypothesis that these are four independent evolutionary entities with different ecological, dispersal and demographical characteristics.
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Affiliation(s)
- Cecili B. Mendes
- Laboratório de Diversidade Genômica, Departamento de Genética e Biologia Evolutiva, IB (USP), São Paulo, SP, Brazil
| | - Jon L. Norenburg
- National Museum of Natural History, Smithsonian Institution, Washington, DC, United States of America
| | - Vera N. Solferini
- Laboratório de Diversidade Genética, Departamento de Genética, Evolução Microbiologia e Imunologia, IB (UNICAMP), Campinas, SP, Brazil
| | - Sónia C. S. Andrade
- Laboratório de Diversidade Genômica, Departamento de Genética e Biologia Evolutiva, IB (USP), São Paulo, SP, Brazil
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21
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Camus C, Faugeron S, Buschmann AH. Assessment of genetic and phenotypic diversity of the giant kelp, Macrocystis pyrifera, to support breeding programs. ALGAL RES 2018. [DOI: 10.1016/j.algal.2018.01.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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22
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Comparative phylogeography of six red algae along the Antarctic Peninsula: extreme genetic depletion linked to historical bottlenecks and recent expansion. Polar Biol 2018. [DOI: 10.1007/s00300-017-2244-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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23
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Troncoso AJ, Bertin A, Osorio R, Arancio G, Gouin N. Comparative population genetics of two dominant plant species of high Andean wetlands reveals complex evolutionary histories and conservation perspectives in Chile’s Norte Chico. CONSERV GENET 2017. [DOI: 10.1007/s10592-017-0957-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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24
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López BA, Macaya EC, Tala F, Tellier F, Thiel M. The variable routes of rafting: stranding dynamics of floating bull kelp Durvillaea antarctica (Fucales, Phaeophyceae) on beaches in the SE Pacific. JOURNAL OF PHYCOLOGY 2017; 53:70-84. [PMID: 27734500 DOI: 10.1111/jpy.12479] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Accepted: 09/05/2016] [Indexed: 06/06/2023]
Abstract
Dispersal on floating seaweeds depends on availability, viability, and trajectories of the rafts. In the southern hemisphere, the bull kelp Durvillaea antarctica is one of the most common floating seaweeds, but phylogeographic studies had shown low connectivity between populations from continental Chile, which could be due to limitations in local supply and dispersal of floating kelps. To test this hypothesis, the spatiotemporal dynamics of kelp strandings were examined in four biogeographic districts along the Chilean coast (28°-42°S). We determined the biomass and demography of stranded individuals on 33 beaches for three subsequent years (2013, 2014, 2015) to examine whether rafting is restricted to certain districts and seasons (winter or summer). Stranded kelps were found on all beaches. Most kelps had only one stipe (one individual), although we also frequently found coalesced holdfasts with mature males and females, which would facilitate successful rafting dispersal, gamete release, and reproduction upon arrival. High biomasses of stranded kelps occurred in the northern-central (30°S-33°S) and southernmost districts (37°S-42°S), and lower biomasses in the northernmost (28°S-30°S) and southern-central districts (33°S-37°S). The highest percentages and sizes of epibionts (Lepas spp.), indicative of prolonged floating periods, were found on stranded kelps in the northernmost and southernmost districts. Based on these results, we conclude that rafting dispersal can vary regionally, being more common in the northernmost and southernmost districts, depending on intrinsic (seaweed biology) and extrinsic factors (shore morphology and oceanography) that affect local supply of kelps and regional hydrodynamics.
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Affiliation(s)
- Boris A López
- Facultad de Ciencias del Mar, Universidad Católica del Norte, Larrondo 1281, Coquimbo, Chile
- Departamento de Acuicultura y Recursos Agroalimentarios, Universidad de Los Lagos, Avenida Fuchslocher 1305, Osorno, Chile
| | - Erasmo C Macaya
- Laboratorio de Estudios Algales (ALGALAB), Departamento de Oceanografía, Universidad de Concepción, Casilla 160-C, Concepción, Chile
- Millennium Nucleus Ecology and Sustainable Management of Oceanic Island (ESMOI), Coquimbo, Chile
- Centro FONDAP de Investigaciones en Dinámica de Ecosistemas Marinos de Altas Latitudes (IDEAL), Valdivia, Chile
| | - Fadia Tala
- Facultad de Ciencias del Mar, Universidad Católica del Norte, Larrondo 1281, Coquimbo, Chile
- Centro de Investigación y Desarrollo Tecnológico en Algas (CIDTA), Universidad Católica del Norte, Larrondo 1281, Coquimbo, Chile
| | - Florence Tellier
- Departamento de Ecología, Facultad de Ciencias, Universidad Católica de la Santísima Concepción, Casilla 297, Concepción, Chile
- Centro de Investigación en Biodiversidad y Ambientes Sustentables (CIBAS), Universidad Católica de la Santísima Concepción, Casilla 297, Concepción, Chile
| | - Martin Thiel
- Facultad de Ciencias del Mar, Universidad Católica del Norte, Larrondo 1281, Coquimbo, Chile
- Millennium Nucleus Ecology and Sustainable Management of Oceanic Island (ESMOI), Coquimbo, Chile
- Centro de Estudios Avanzados en Zonas Áridas, CEAZA, Coquimbo, Chile
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25
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Transverse Alpine Speciation Driven by Glaciation. Trends Ecol Evol 2016; 31:916-926. [DOI: 10.1016/j.tree.2016.08.009] [Citation(s) in RCA: 96] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Revised: 08/26/2016] [Accepted: 08/26/2016] [Indexed: 01/19/2023]
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26
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Guillemin ML, Valero M, Morales Collio K, Pinochet Sanchez R, Henríquez Espinosa M, Silva AX. Microsatellite markers and cytoplasmic sequences reveal contrasting pattern of spatial genetic structure in the red algae species complex Mazzaella laminarioides. JOURNAL OF PHYCOLOGY 2016; 52:806-816. [PMID: 27317474 DOI: 10.1111/jpy.12440] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Accepted: 05/04/2016] [Indexed: 06/06/2023]
Abstract
Mazzaella laminarioides is a common haploid-diploid red alga that forms dense beds. This alga has a wide distributional range, covering 3,500 km of the Chilean coast, but is restricted to high rocky intertidal zones. Recently, the existence of three highly divergent genetic lineages was demonstrated for this taxon, and two cytoplasmic markers were used to determine that these lineages are distributed in strict parapatry. Here, using 454 next-generation sequencing, we developed polymorphic microsatellite loci that cross amplify in all three cytoplasmic lineages. Six sites (i.e., two sites within each lineage) were analyzed using nine microsatellite loci. Our work shows that, although substantial cytoplasmic differentiation occurs within M. laminarioides, the microsatellite loci did not retrieve three nuclear genetic clusters as expected. Indeed, while the northernmost and southernmost cytoplasmic lineages form two strongly divergent nuclear groups characterized by diagnostic alleles, the third cytoplasmic lineage did not form a third nuclear independent group. It is possible that inter-lineage gene exchange has occurred, particularly at sites along the contact zone between the different cytoplasmic lineages. This nuclear-cytoplasmic incongruence in M. laminarioides could be explained by incomplete lineage sorting of the nuclear genes or asymmetric introgressive hybridization between the lineages. Finally, highly significant heterozygote deficiencies (suggesting occurrence of intergametophytic selfing) were observed in the three small northernmost sites while the large southernmost sites generally approached panmixia.
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Affiliation(s)
- Marie-Laure Guillemin
- Instituto de Ciencias Ambientales y Evolutivas, Facultad de Ciencias, Universidad Austral de Chile, Casilla 567, Valdivia, Chile
- CNRS, Sorbonne Universités, UPMC University Paris VI, UMI 3614, Evolutionary Biology and Ecology of Algae, Station Biologique de Roscoff, CS 90074, Place G. Tessier, 296888, Roscoff, France
| | - Myriam Valero
- CNRS, Sorbonne Universités, UPMC University Paris VI, UMI 3614, Evolutionary Biology and Ecology of Algae, Station Biologique de Roscoff, CS 90074, Place G. Tessier, 296888, Roscoff, France
| | - Kennia Morales Collio
- Instituto de Ciencias Ambientales y Evolutivas, Facultad de Ciencias, Universidad Austral de Chile, Casilla 567, Valdivia, Chile
| | - Ramona Pinochet Sanchez
- Instituto de Ciencias Ambientales y Evolutivas, Facultad de Ciencias, Universidad Austral de Chile, Casilla 567, Valdivia, Chile
| | - Miguel Henríquez Espinosa
- Instituto de Ciencias Ambientales y Evolutivas, Facultad de Ciencias, Universidad Austral de Chile, Casilla 567, Valdivia, Chile
| | - Andrea X Silva
- AUSTRAL-omics, Facultad de Ciencias, Universidad Austral de Chile, Casilla 567, Valdivia, Chile
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Ewers‐Saucedo C, Pringle JM, Sepúlveda HH, Byers JE, Navarrete SA, Wares JP. The oceanic concordance of phylogeography and biogeography: a case study in Notochthamalus. Ecol Evol 2016; 6:4403-20. [PMID: 27386084 PMCID: PMC4930989 DOI: 10.1002/ece3.2205] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Revised: 04/27/2016] [Accepted: 05/02/2016] [Indexed: 11/11/2022] Open
Abstract
Dispersal and adaptation are the two primary mechanisms that set the range distributions for a population or species. As such, understanding how these mechanisms interact in marine organisms in particular - with capacity for long-range dispersal and a poor understanding of what selective environments species are responding to - can provide useful insights for the exploration of biogeographic patterns. Previously, the barnacle Notochthamalus scabrosus has revealed two evolutionarily distinct lineages with a joint distribution that suggests an association with one of the two major biogeographic boundaries (~30°S) along the coast of Chile. However, spatial and genomic sampling of this system has been limited until now. We hypothesized that given the strong oceanographic and environmental shifts associated with the other major biogeographic boundary (~42°S) for Chilean coastal invertebrates, the southern mitochondrial lineage would dominate or go to fixation in locations further to the south. We also evaluated nuclear polymorphism data from 130 single nucleotide polymorphisms to evaluate the concordance of the signal from the nuclear genome with that of the mitochondrial sample. Through the application of standard population genetic approaches along with a Lagrangian ocean connectivity model, we describe the codistribution of these lineages through a simultaneous evaluation of coastal lineage frequencies, an approximation of larval behavior, and current-driven dispersal. Our results show that this pattern could not persist without the two lineages having distinct environmental optima. We suggest that a more thorough integration of larval dynamics, explicit dispersal models, and near-shore environmental analysis can explain much of the coastal biogeography of Chile.
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Affiliation(s)
| | - James M. Pringle
- Institute for the Study of Earth, Ocean, and SpaceUniversity of New HampshireDurhamNew Hampshire03824
| | | | - James E. Byers
- Odum School of EcologyUniversity of GeorgiaAthensGeorgia30602
| | - Sergio A. Navarrete
- Estación Costera de Investigaciones Marinas Las Cruces and Center for Marine ConservationPontificia Universidad Católica de ChileCasilla 114DSantiagoChile
| | - John P. Wares
- Odum School of EcologyUniversity of GeorgiaAthensGeorgia30602
- Department of GeneticsUniversity of GeorgiaAthensGeorgia30602
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Aguilera MA, Valdivia N, Broitman BR. Facilitative Effect of a Generalist Herbivore on the Recovery of a Perennial Alga: Consequences for Persistence at the Edge of Their Geographic Range. PLoS One 2015; 10:e0146069. [PMID: 26716986 PMCID: PMC4696856 DOI: 10.1371/journal.pone.0146069] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Accepted: 12/11/2015] [Indexed: 11/22/2022] Open
Abstract
Understanding the impacts of consumers on the abundance, growth rate, recovery and persistence of their resources across their distributional range can shed light on the role of trophic interactions in determining species range shifts. Here, we examined if consumptive effects of the intertidal grazer Scurria viridula positively influences the abundance and recovery from disturbances of the alga Mazzaella laminarioides at the edge of its geographic distributions in northern-central Chilean rocky shores. Through field experiments conducted at a site in the region where M. laminarioides overlaps with the polar range edge of S. viridula, we estimated the effects of grazing on different life stages of M. laminarioides. We also used long-term abundance surveys conducted across ~700 km of the shore to evaluate co-occurrence patterns of the study species across their range overlap. We found that S. viridula had positive net effects on M. laminarioides by increasing its cover and re-growth from perennial basal crusts. Probability of occurrence of M. laminarioides increased significantly with increasing density of S. viridula across the range overlap. The negative effect of S. viridula on the percentage cover of opportunistic green algae—shown to compete for space with corticated algae—suggests that competitive release may be part of the mechanism driving the positive effect of the limpet on the abundance and recovery from disturbance of M. laminarioides. We suggest that grazer populations contribute to enhance the abundance of M. laminarioides, facilitating its recolonization and persistence at its distributional range edge. Our study highlights that indirect facilitation can determine the recovery and persistence of a resource at the limit of its distribution, and may well contribute to the ecological mechanisms governing species distributions and range shifts.
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Affiliation(s)
- Moisés A. Aguilera
- Centro de Estudios Avanzados en Zonas Áridas (CEAZA), Universidad Católica del Norte, Ossandón 877, Coquimbo, Chile
- * E-mail:
| | - Nelson Valdivia
- Instituto de Ciencias Marinas y Limnológicas, Facultad de Ciencias, Universidad Austral de Chile, Campus Isla Teja s/n,Valdivia, Chile
| | - Bernardo R. Broitman
- Centro de Estudios Avanzados en Zonas Áridas (CEAZA), Universidad Católica del Norte, Ossandón 877, Coquimbo, Chile
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The bladed Bangiales (Rhodophyta) of the South Eastern Pacific: Molecular species delimitation reveals extensive diversity. Mol Phylogenet Evol 2015; 94:814-826. [PMID: 26484942 DOI: 10.1016/j.ympev.2015.09.027] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Revised: 09/22/2015] [Accepted: 09/30/2015] [Indexed: 10/22/2022]
Abstract
A molecular taxonomic study of the bladed Bangiales of the South Eastern Pacific (coast of Chile) was undertaken based on sequence data of the mitochondrial COI and chloroplast rbcL for 193 specimens collected from Arica (18°S) in the north to South Patagonia (53°S) in the south. The results revealed for the first time that four genera, Porphyra, Pyropia, Fuscifolium and Wildemania were present in the region. Species delimitation was determined based on a combination of a General Mixed Yule Coalescence model (GMYC) and Automatic Barcode Gap Discovery (ABGD) coupled with detection of monophyly in tree reconstruction. The overall incongruence between the species delimitation methods within each gene was 29%. The GMYC method led to over-splitting groups, whereas the ABGD method had a tendency to lump groups. Taking a conservative approach to the number of putative species, at least 18 were recognized and, with the exception of the recently described Pyropia orbicularis, all were new to the Chilean flora. Porphyra and Pyropia were the most diverse genera with eight 'species' each, whereas only a 'single' species each was found for Fuscifolium and Wildemania. There was also evidence of recently diverging groups: Wildemania sp. was distinct but very closely related to W. amplissima from the Northern Hemisphere and raises questions in relation to such disjunct distributions. Pyropia orbicularis was very closely related to two other species, making species delimitation very difficult but provides evidence of an incipient speciation. The difference between the 'species' discovered and those previously reported for the region is discussed in relation to the difficulty of distinguishing species based on morphological identification.
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30
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Deep genetic divergence between austral populations of the red alga Gigartina skottsbergii reveals a cryptic species endemic to the Antarctic continent. Polar Biol 2015. [DOI: 10.1007/s00300-015-1762-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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31
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Neiva J, Assis J, Coelho NC, Fernandes F, Pearson GA, Serrão EA. Genes Left Behind: Climate Change Threatens Cryptic Genetic Diversity in the Canopy-Forming Seaweed Bifurcaria bifurcata. PLoS One 2015; 10:e0131530. [PMID: 26177545 PMCID: PMC4503591 DOI: 10.1371/journal.pone.0131530] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Accepted: 06/03/2015] [Indexed: 11/30/2022] Open
Abstract
The global redistribution of biodiversity will intensify in the coming decades of climate change, making projections of species range shifts and of associated genetic losses important components of conservation planning. Highly-structured marine species, notably brown seaweeds, often harbor unique genetic variation at warmer low-latitude rear edges and thus are of particular concern. Here, a combination of Ecological Niche Models (ENMs) and molecular data is used to forecast the potential near-future impacts of climate change for a warm-temperate, canopy forming seaweed, Bifurcaria bifurcata. ENMs for B. bifurcata were developed using marine and terrestrial climatic variables, and its range projected for 2040-50 and 2090-2100 under two greenhouse emission scenarios. Geographical patterns of genetic diversity were assessed by screening 18 populations spawning the entire distribution for two organelle genes and 6 microsatellite markers. The southern limit of B. bifurcata was predicted to shift northwards to central Morocco by the mid-century. By 2090-2100, depending on the emission scenario, it could either retreat further north to western Iberia or be relocated back to Western Sahara. At the opposing margin, B. bifurcata was predicted to expand its range to Scotland or even Norway. Microsatellite diversity and endemism were highest in Morocco, where a unique and very restricted lineage was also identified. Our results imply that B. bifurcata will maintain a relatively broad latitudinal distribution. Although its persistence is not threatened, the predicted extirpation of a unique southern lineage or even the entire Moroccan diversity hotspot will erase a rich evolutionary legacy and shrink global diversity to current (low) European levels. NW Africa and similarly understudied southern regions should receive added attention if expected range changes and diversity loss of warm-temperate species is not to occur unnoticed.
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Affiliation(s)
- João Neiva
- Centro de Ciências do Mar da Universidade do Algarve, Faro, Portugal
| | - Jorge Assis
- Centro de Ciências do Mar da Universidade do Algarve, Faro, Portugal
| | - Nelson C. Coelho
- Centro de Ciências do Mar da Universidade do Algarve, Faro, Portugal
| | | | - Gareth A. Pearson
- Centro de Ciências do Mar da Universidade do Algarve, Faro, Portugal
| | - Ester A. Serrão
- Centro de Ciências do Mar da Universidade do Algarve, Faro, Portugal
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Muangmai N, Fraser CI, Zuccarello GC. Contrasting patterns of population structure and demographic history in cryptic species of Bostrychia intricata (Rhodomelaceae, Rhodophyta) from New Zealand. JOURNAL OF PHYCOLOGY 2015; 51:574-585. [PMID: 26986671 DOI: 10.1111/jpy.12305] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Accepted: 02/24/2015] [Indexed: 06/05/2023]
Abstract
Spatial patterns of genetic diversity provide insight into the demography and history of species. Morphologically similar but genetically distinct "cryptic" species are increasingly being recognized in marine organisms through molecular analyses. Such species are, on closer inspection, often discovered to display contrasting life histories or occasionally minor morphological differences; molecular tools can thus be useful indicators of diversity. Bostrychia intricata, a marine red alga, is widely distributed throughout the Southern Hemisphere and comprises many cryptic species. We used mitochondrial cytochrome c oxidase I gene sequences to assess the genetic variation, population genetic structure, and demographic history of B. intricata in New Zealand. Our results supported the existence of three cryptic species of B. intricata (N2, N4, and N5) in New Zealand. Cryptic species N4, which was found throughout New Zealand, showed a higher genetic diversity and wider distribution than the other two species, which were only found in the North Island and northern South Island. Our analyses showed low to moderate genetic differentiation among eastern North Island populations for cryptic species N2, but high differentiation among North and South Island populations for N4, suggesting different population structure between these cryptic species. Data also indicated that N2 has recently undergone population expansion, probably since the Last Glacial Maximum (LGM), while the higher genetic diversity in N4 populations suggests persistence in situ through the LGM. The contrasting population structures and inferred demographic histories of these species highlight that life history can vary greatly even among morphologically indistinguishable taxa.
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Affiliation(s)
- Narongrit Muangmai
- School of Biological Sciences, Victoria University of Wellington, Wellington, 6041, New Zealand
| | - Ceridwen I Fraser
- Fenner School of Environmental and Society, ANU College of Medicine, Biology & Environment, Australian National University, Canberra, ACT, 2601, Australia
| | - Giuseppe C Zuccarello
- School of Biological Sciences, Victoria University of Wellington, Wellington, 6041, New Zealand
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Tapia FJ, Largier JL, Castillo M, Wieters EA, Navarrete SA. Latitudinal discontinuity in thermal conditions along the nearshore of central-northern Chile. PLoS One 2014; 9:e110841. [PMID: 25334020 PMCID: PMC4204934 DOI: 10.1371/journal.pone.0110841] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Accepted: 09/17/2014] [Indexed: 11/18/2022] Open
Abstract
Over the past decade, evidence of abrupt latitudinal changes in the dynamics, structure and genetic variability of intertidal and subtidal benthic communities along central-northern Chile has been found consistently at 30–32°S. Changes in the advective and thermal environment in nearshore waters have been inferred from ecological patterns, since analyses of in situ physical data have thus far been missing. Here we analyze a unique set of shoreline temperature data, gathered over 4–10 years at 15 sites between 28–35°S, and combine it with satellite-derived winds and sea surface temperatures to investigate the latitudinal transition in nearshore oceanographic conditions suggested by recent ecological studies. Our results show a marked transition in thermal conditions at 30–31°S, superimposed on a broad latitudinal trend, and small-scale structures associated with cape-and-bay topography. The seasonal cycle dominated temperature variability throughout the region, but its relative importance decreased abruptly south of 30–31°S, as variability at synoptic and intra-seasonal scales became more important. The response of shoreline temperatures to meridional wind stress also changed abruptly at the transition, leading to a sharp drop in the occurrence of low-temperature waters at northern sites, and a concurrent decrease in corticated algal biomass. Together, these results suggest a limitation of nitrate availability in nearshore waters north of the transition. The localized alongshore change results from the interaction of latitudinal trends (e.g., wind stress, surface warming, inertial period) with a major headland-bay system (Punta Lengua de Vaca at 30.25°S), which juxtaposes a southern stretch of coast characterized by upwelling with a northern stretch of coast characterized by warm surface waters and stratification. This transition likely generates a number of latitude-dependent controls on ecological processes in the nearshore that can explain species-specific effects, and add strength to the suggestion of an oceanography-driven, major spatial transition in coastal communities at 30–31°S.
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Affiliation(s)
- Fabian J. Tapia
- Estación Costera de Investigaciones Marinas - Las Cruces, Pontificia Universidad Católica de Chile, Santiago, Chile
- Departamento de Oceanografía & COPAS Sur-Austral, Universidad de Concepción, Concepción, Chile
- * E-mail:
| | - John L. Largier
- Bodega Marine Laboratory, University of California Davis, Davis, California, United States of America
| | - Manuel Castillo
- Estación Costera de Investigaciones Marinas - Las Cruces, Pontificia Universidad Católica de Chile, Santiago, Chile
- Departamento de Oceanografía & COPAS Sur-Austral, Universidad de Concepción, Concepción, Chile
| | - Evie A. Wieters
- Estación Costera de Investigaciones Marinas - Las Cruces, Pontificia Universidad Católica de Chile, Santiago, Chile
- Center for Marine Conservation - Las Cruces, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Sergio A. Navarrete
- Estación Costera de Investigaciones Marinas - Las Cruces, Pontificia Universidad Católica de Chile, Santiago, Chile
- Center for Marine Conservation - Las Cruces, Pontificia Universidad Católica de Chile, Santiago, Chile
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Scorched mussels (BIVALVIA: MYTILIDAE: BRACHIDONTINAE) from the temperate coasts of South America: phylogenetic relationships, trans-Pacific connections and the footprints of Quaternary glaciations. Mol Phylogenet Evol 2014; 82 Pt A:60-74. [PMID: 25451805 DOI: 10.1016/j.ympev.2014.10.002] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Revised: 08/26/2014] [Accepted: 10/03/2014] [Indexed: 11/22/2022]
Abstract
This study addresses aspects of the phylogeny and phylogeography of scorched mussels (BIVALVIA: MYTILIDAE: BRACHIDONTINAE) from southern South America (Argentina and Chile), as well as their ecophylogenetic implications. Relationships were inferred from sequences of two nuclear (28S and 18S) and one mitochondrial (COI) genes, using Bayesian and maximum likelihood analyses. Our results indicate that the monophyletic BRACHIDONTINAE include three well supported clades: [i] Brachidontes Swainson (=Hormomya Mörch), [ii] Ischadium Jukes-Browne+Geukensia van de Poel, and [iii] Austromytilus Laseron+Mytilisepta Habe (usually considered a member of the SEPTIFERINAE)+Perumytilus Olsson. Species of clade [iii] are distributed along the temperate coasts of the Pacific Ocean. Available evidence supports divergence between Austromytilus (Australia) and Perumytilus (South American) following the breakup of Australian, Antarctic and South American shelves. Four brachidontins occur in southern South America: Brachidontes rodriguezii (d'Orbigny), B. granulatus (Hanley), and two genetically distinct clades of Perumytilus. The latter are confined to the Chile-Peru (North Clade) and Magellanic (South Clade) Biogeographic Provinces, respectively warm- and cold-temperate. The South Clade is the only brachidontin restricted to cold-temperate waters. Biogeographic considerations and the fossil record prompted the hypothesis that the South Clade originated from the North Clade by incipient peripatric differentiation, followed by isolation during the Quaternary glaciations, genetic differentiation in the non-glaciated coasts of eastern Patagonia, back-expansion over southern Chile following post-LGM de-glaciation, and development of a secondary contact zone between the two clades in south-central Chile. Evidence of upper Pleistocene expansion of the South Clade parallels similar results on other organisms that have colonized coastal ecosystems from eastern Patagonia since the LGM, apparently occupying free ecological space. We emphasize that the assembly of communities cannot be explained solely in terms of environmental drivers, as history also matters.
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Haye PA, Segovia NI, Muñoz-Herrera NC, Gálvez FE, Martínez A, Meynard A, Pardo-Gandarillas MC, Poulin E, Faugeron S. Phylogeographic structure in benthic marine invertebrates of the southeast Pacific coast of Chile with differing dispersal potential. PLoS One 2014; 9:e88613. [PMID: 24586356 PMCID: PMC3929388 DOI: 10.1371/journal.pone.0088613] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2012] [Accepted: 01/15/2014] [Indexed: 11/18/2022] Open
Abstract
The role of dispersal potential on phylogeographic structure, evidenced by the degree of genetic structure and the presence of coincident genetic and biogeographic breaks, was evaluated in a macrogeographic comparative approach along the north-central coast of Chile, across the biogeographic transition zone at 30°S. Using 2,217 partial sequences of the mitochondrial Cytochrome Oxidase I gene of eight benthic invertebrate species along ca. 2,600 km of coast, we contrasted dispersal potential with genetic structure and determined the concordance between genetic divergence between biogeographic regions and the biogeographic transition zone at 30°S. Genetic diversity and differentiation highly differed between species with high and low dispersal potential. Dispersal potential, sometimes together with biogeographic region, was the factor that best explained the genetic structure of the eight species. The three low dispersal species, and one species assigned to the high dispersal category, had a phylogeographic discontinuity coincident with the biogeographic transition zone at 30°S. Furthermore, coalescent analyses based on the isolation-with-migration model validate that the split between biogeographic regions north and south of 30°S has a historic origin. The signatures of the historic break in high dispersers is parsimoniously explained by the homogenizing effects of gene flow that have erased the genetic signatures, if ever existed, in high dispersers. Of the four species with structure across the break, only two had significant albeit very low levels of asymmetric migration across the transition zone. Historic processes have led to the current biogeographic and phylogeographic structure of marine species with limited dispersal along the north-central coast of Chile, with a strong lasting impact in their genetic structure.
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Affiliation(s)
- Pilar A. Haye
- Laboratorio de Diversidad Molecular, Departamento de Biología Marina, Facultad de Ciencias del Mar, Universidad Católica del Norte & Centro de Estudios Avanzados en Zonas Áridas (CEAZA), Coquimbo, Chile
- Interdisciplinary Center for Aquaculture Research (INCAR), Universidad de Concepción, Concepción, Chile
| | - Nicolás I. Segovia
- Laboratorio de Diversidad Molecular, Departamento de Biología Marina, Facultad de Ciencias del Mar, Universidad Católica del Norte & Centro de Estudios Avanzados en Zonas Áridas (CEAZA), Coquimbo, Chile
- Instituto de Ecología y Biodiversidad, Departamento de Ciencias Ecológicas, Universidad de Chile, Santiago, Chile
| | - Natalia C. Muñoz-Herrera
- Laboratorio de Diversidad Molecular, Departamento de Biología Marina, Facultad de Ciencias del Mar, Universidad Católica del Norte & Centro de Estudios Avanzados en Zonas Áridas (CEAZA), Coquimbo, Chile
- Interdisciplinary Center for Aquaculture Research (INCAR), Universidad de Concepción, Concepción, Chile
| | - Francisca E. Gálvez
- Laboratorio de Diversidad Molecular, Departamento de Biología Marina, Facultad de Ciencias del Mar, Universidad Católica del Norte & Centro de Estudios Avanzados en Zonas Áridas (CEAZA), Coquimbo, Chile
| | - Andrea Martínez
- Instituto de Ecología y Biodiversidad, Departamento de Ciencias Ecológicas, Universidad de Chile, Santiago, Chile
| | - Andrés Meynard
- Centro de Conservación Marina, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - María C. Pardo-Gandarillas
- Instituto de Ecología y Biodiversidad, Departamento de Ciencias Ecológicas, Universidad de Chile, Santiago, Chile
- Centro de Conservación Marina, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Elie Poulin
- Instituto de Ecología y Biodiversidad, Departamento de Ciencias Ecológicas, Universidad de Chile, Santiago, Chile
| | - Sylvain Faugeron
- Centro de Conservación Marina, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
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Haye PA, Muñoz-Herrera NC. Isolation with differentiation followed by expansion with admixture in the tunicate Pyura chilensis. BMC Evol Biol 2013; 13:252. [PMID: 24238017 PMCID: PMC3840596 DOI: 10.1186/1471-2148-13-252] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2013] [Accepted: 10/29/2013] [Indexed: 11/21/2022] Open
Abstract
Background Pyura chilensis, a tunicate commercially exploited as food resource in Chile, is subject to management strategies, including restocking. The goal of this study was to examine the genetic structure of P. chilensis using information from a mitochondrial gene (Cytochrome Oxidase I, COI) and a nuclear gene (Elongation 1 alpha, EF1a), to characterize the geographic distribution of genetic diversity and differentiation, and to identify the main processes that have shaped it. We analyzed 268 and 208 sequences of COI and EF1a, respectively, from samples of eight local populations covering ca. 1800 km. Results For Pyura chilensis, partial sequences of the gene COI revealed three highly supported haplogroups that diverged 260000 to 470000 years ago. Two haplogroups currently are widely distributed and sympatric, while one is dominant only in Los Molinos (LM, 39°50′S). The two widespread COI haplogroups underwent a geographic expansion during an interglacial period of the Late Pleistocene ca. 100000 years ago. The nuclear gene was less divergent and did not resolve the COI haplogroups. Bayesian clustering of the nuclear gene’s SNPs revealed that individuals from the two widespread COI haplogroups were mostly assigned to two of the three detected clusters and had a marked degree of admixture. The third cluster predominated in LM and showed low admixture. Haplotypic diversity of both genes was very high, there was no isolation by distance, and most localities were genetically undifferentiated; only LM was consistently differentiated with both genes analyzed. Conclusions Pyura chilensis has less genetic structure than expected given its life history, which could be a consequence of dispersal on ship hulls. The only differentiated local population analyzed was LM. Coincidentally, it is the one furthest away from main maritime routes along the coast of Chile. The use of mitochondrial and nuclear markers allowed detection of divergent mitochondrial haplogroups in P. chilensis, two of which revealed nuclear admixture. The genetic structure of P. chilensis has likely been shaped by Pleistocene’s climatic effect on sea level leading to population contraction with isolation, followed by geographic range expansions with concomitant secondary contact and admixture.
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Affiliation(s)
- Pilar A Haye
- Laboratorio de Diversidad Molecular, Departamento de Biología Marina, Facultad de Ciencias del Mar, Universidad Católica del Norte, Casilla 117, Coquimbo, Chile.
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