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Ke Z, Zhou K, Hou M, Luo H, Li Z, Pan X, Zhou J, Jing T, Ye H. Characterization of the Complete Mitochondrial Genome of the Elongate Loach and Its Phylogenetic Implications in Cobitidae. Animals (Basel) 2023; 13:3841. [PMID: 38136877 PMCID: PMC10740543 DOI: 10.3390/ani13243841] [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: 10/25/2023] [Revised: 12/01/2023] [Accepted: 12/02/2023] [Indexed: 12/24/2023] Open
Abstract
The elongate loach is an endemic fish in China. Previous studies have provided some insights into the mitochondrial genome composition and the phylogenetic relationships of the elongate loach inferred using protein-coding genes (PCGs), yet detailed information about it remains limited. Therefore, in this study we sequenced the complete mitochondrial genome of the elongate loach and analyzed its structural characteristics. The PCGs and mitochondrial genome were used for selective stress analysis and genomic comparative analysis. The complete mitochondrial genome of the elongate loach, together with those of 35 Cyprinidae species, was used to infer the phylogenetic relationships of the Cobitidae family through maximum likelihood (ML) reconstruction. The results showed that the genome sequence has a full length of 16,591 bp, which includes 13 PCGs, 22 transfer RNA genes (tRNA), 2 ribosomal RNA genes (rRNA), and 2 non-coding regions (CR D-loop and light chain sub-chain replication origin OL). Overall, the elongate loach shared the same gene arrangement and composition of the mitochondrial genes with other teleost fishes. The Ka/Ks ratios of all mitochondrial PCGs were less than 1, indicating that all of the PCGs were evolving under purifying selection. Genome comparison analyses showed a significant sequence homology of species of Leptobotia. A significant identity between L. elongata and the other five Leptobotia species was observed in the visualization result, except for L. mantschurica, which lacked the tRNA-Arg gene and had a shorter tRNA-Asp gene. The phylogenetic tree revealed that the Cobitidae species examined here can be grouped into two clades, with the elongate loach forming a sister relationship with L. microphthalma. This study could provide additional inferences for a better understanding of the phylogenetic relationships among Cobitidae species.
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Affiliation(s)
- Zhenlin Ke
- Integrative Science Center of Germplasm Creation in Western China (Chongqing) Science City, Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, College of Fisheries, Southwest University, Chongqing 402460, China; (Z.K.); (M.H.); (H.L.); (T.J.)
- Key Laboratory of Aquatic Science of Chongqing, Chongqing 400175, China
| | - Kangqi Zhou
- Guangxi Key Laboratory of Aquatic Genetic Breeding and Healthy Aquaculture, Guangxi Academy of Fishery Sciences, Nanning 530021, China; (K.Z.); (Z.L.); (X.P.)
| | - Mengdan Hou
- Integrative Science Center of Germplasm Creation in Western China (Chongqing) Science City, Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, College of Fisheries, Southwest University, Chongqing 402460, China; (Z.K.); (M.H.); (H.L.); (T.J.)
- Key Laboratory of Aquatic Science of Chongqing, Chongqing 400175, China
| | - Hui Luo
- Integrative Science Center of Germplasm Creation in Western China (Chongqing) Science City, Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, College of Fisheries, Southwest University, Chongqing 402460, China; (Z.K.); (M.H.); (H.L.); (T.J.)
- Key Laboratory of Aquatic Science of Chongqing, Chongqing 400175, China
| | - Zhe Li
- Guangxi Key Laboratory of Aquatic Genetic Breeding and Healthy Aquaculture, Guangxi Academy of Fishery Sciences, Nanning 530021, China; (K.Z.); (Z.L.); (X.P.)
| | - Xianhui Pan
- Guangxi Key Laboratory of Aquatic Genetic Breeding and Healthy Aquaculture, Guangxi Academy of Fishery Sciences, Nanning 530021, China; (K.Z.); (Z.L.); (X.P.)
| | - Jian Zhou
- Fisheries Institute, Sichuan Academy of Agricultural Sciences, Chengdu 611731, China
| | - Tingsen Jing
- Integrative Science Center of Germplasm Creation in Western China (Chongqing) Science City, Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, College of Fisheries, Southwest University, Chongqing 402460, China; (Z.K.); (M.H.); (H.L.); (T.J.)
- Key Laboratory of Aquatic Science of Chongqing, Chongqing 400175, China
| | - Hua Ye
- Integrative Science Center of Germplasm Creation in Western China (Chongqing) Science City, Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, College of Fisheries, Southwest University, Chongqing 402460, China; (Z.K.); (M.H.); (H.L.); (T.J.)
- Key Laboratory of Aquatic Science of Chongqing, Chongqing 400175, China
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2
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Li CYJ, Tsai WP, Ranatunga RRMKP, Samidon M, Liu SYV. Genetic stock structure of the silky shark Carcharhinus falciformis in the Indo-Pacific Ocean. PLoS One 2023; 18:e0292743. [PMID: 37824585 PMCID: PMC10569576 DOI: 10.1371/journal.pone.0292743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 09/27/2023] [Indexed: 10/14/2023] Open
Abstract
The silky shark, Carcharhinus falciformis, is a cosmopolitan species commonly caught as a bycatch for longline fisheries. However, the genetic stock structure for the Indo-Pacific Ocean is not well-defined yet. Here, we used eight microsatellite loci to examine the genetic stock structure and effective population size of 307 silky sharks across 5 Indo-Pacific sampling locations. A major genetic break was found between Aceh and the remaining locations (FST = 0.0505-0.0828, p = 0.001). The Indian Ocean displayed a slightly lower effective population estimate (Ne) compared to the Pacific Ocean, potentially due to the higher fishing pressure in the Indian Ocean region. The lowest Ne was found in the Aceh population (Ne = 2.3), suggesting it might be a small and endemic population. These findings offer valuable information for the conservation and management of the silky shark. We suggest that the population around Aceh waters constitutes a distinct stock and should be managed independently. Further investigations into migratory and movement patterns are needed to define the boundaries of different stocks, ensuring effective management the silky shark across the Indo-Pacific region.
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Affiliation(s)
- Chia-Yun Joanne Li
- Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung, Taiwan
| | - Wen-Pei Tsai
- Department of Fisheries Production and Management, National Kaohsiung University of Science and Technology, Kaohsiung, Taiwan
| | - R. R. M. K. P. Ranatunga
- Centre for Marine Science and Technology, Department of Zoology, University of Sri Jayewardenepura, Nugegoda, Sri Lanka
| | - Munandar Samidon
- Department of Marine Science, Teuku Umar University, Aceh Barat, Indonesia
| | - Shang Yin Vanson Liu
- Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung, Taiwan
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3
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Kottillil S, Rao C, Bowen BW, Shanker K. Phylogeography of sharks and rays: a global review based on life history traits and biogeographic partitions. PeerJ 2023; 11:e15396. [PMID: 37283899 PMCID: PMC10239618 DOI: 10.7717/peerj.15396] [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: 06/13/2022] [Accepted: 04/20/2023] [Indexed: 06/08/2023] Open
Abstract
Considerable research exists on the life history traits, evolutionary history, and environmental factors that shape the population genetic structure of marine organisms, including sharks and rays. Conservation concerns are particularly strong for this group as they are highly susceptible to anthropogenic stressors due to a combination of life history traits including late maturity and low fecundity. Here, we provide a review and synthesis of the global phylogeography of sharks and rays. We examined existing data for 40 species of sharks belonging to 17 genera and 19 species of rays belonging to 11 genera. Median joining haplotype networks were constructed for each species for the mtDNA cytochrome C oxidase subunit I (COI), and an Analysis of Molecular Variance (AMOVA) was conducted to understand patterns of genetic diversity and structure across the three major ocean basins-the Indian, Atlantic and Pacific Oceans. Haplotype networks showed very shallow coalescence in most species, a finding previously reported for marine teleosts. Star topologies were predominant among sharks while complex mutational topologies predominated among rays, a finding we attribute to extremely limited dispersal in the early life history of rays. Population structuring varied amongst species groups, apparently due to differences in life history traits including reproductive philopatry, site fidelity, pelagic habitat, migratory habits, and dispersal ability. In comparison to reef-associated and demersal species, pelagic and semi pelagic species showed lower levels of structure between and within ocean basins. As expected, there is variation between taxa and groups, but there are also some broad patterns that can guide management and conservation strategies.
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Affiliation(s)
- Sudha Kottillil
- Centre for Ecological Sciences, Indian Institute of Science, Bengaluru, Karnataka, India
- Department of Energy and Environment, TERI School of Advanced Studies, New Delhi, India
| | - Chetan Rao
- Dakshin Foundation, Bengaluru, Karnataka, India
| | - Brian W. Bowen
- Hawai‘i Institute of Marine Biology, University of Hawaii, Kaneohe, Hawai‘i, United States of America
| | - Kartik Shanker
- Centre for Ecological Sciences, Indian Institute of Science, Bengaluru, Karnataka, India
- Dakshin Foundation, Bengaluru, Karnataka, India
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4
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Characterization of mitochondrial genome of Indian Ocean blue-spotted maskray, Neotrygon indica and its phylogenetic relationship within Dasyatidae Family. Int J Biol Macromol 2022; 223:458-467. [PMID: 36347369 DOI: 10.1016/j.ijbiomac.2022.10.277] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2022] [Revised: 10/11/2022] [Accepted: 10/28/2022] [Indexed: 11/06/2022]
Abstract
The present study characterized complete mitochondrial genome of Blue-spotted maskray, Neotrygon indica and studied the evolutionary relationship of the species within the Dasyatidae family. The total length of the mitogenome was 17,974 bp including 37 genes and a non-coding control region. The average frequency of nucleotides in protein-coding genes was A: 29.1 %, T: 30.2 %, G: 13.0 % and C: 27.7 % with AT content of 59.3 %. The values of AT and GC skewness were -0.018 and -0.338, respectively. Comparative analyses showed a large number of average synonymous substitutions per synonymous site (Ks) in gene NADH4 (5.07) followed by NADH5 (4.72). High values of average number of non-synonymous substitutions per non-synonymous site (Ka) were observed in genes ATPase8 (0.54) and NADH2 (0.44). Genes NADH4L and NADH2 showed high interspecific genetic distance values of 0.224 ± 0.001 and 0.213 ± 0.002, respectively. Heat map analysis showed variation in codon usage among different species of the Dasyatidae family. The phylogenetic tree showed a sister relationship between the Dasyatinae and the Neotrygoninae subfamilies. Neotrygon indica formed as a sister species to the clade consisting of N. varidens and N. orientalis. Based on the present results, Neotrygon indica could have diverged from the common ancestor of the two latter in the Plio-Pleistocene. The present study showed distinct characteristics of N. indica from its congeners through comparative mitogenomics.
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5
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Jamaludin NA, Jamaluddin JAF, Rahim MA, Mohammed Akib NA, Ratmuangkhwang S, Mohd Arshaad W, Mohd Nor SA. Mitochondrial marker implies fishery separate management units for spotted sardinella, Amblygaster sirm (Walbaum, 1792) populations in the South China Sea and the Andaman Sea. PeerJ 2022; 10:e13706. [PMID: 35860045 PMCID: PMC9290996 DOI: 10.7717/peerj.13706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 06/19/2022] [Indexed: 01/17/2023] Open
Abstract
The spotted sardinella, Amblygaster sirm (Walbaum, 1792), is a commercial sardine commonly caught in Malaysia. Lack of management of these marine species in Malaysian waters could lead to overfishing and potentially declining fish stock populations. Therefore, sustainable management of this species is of paramount importance to ensure its longevity. As such, molecular information is vital in determining the A. sirm population structure and management strategy. In the present study, mitochondrial DNA Cytochrome b was sequenced from 10 A. sirm populations: the Andaman Sea (AS) (two), South China Sea (SCS) (six), Sulu Sea (SS) (one), and Celebes Sea (CS) (one). Accordingly, the intra-population haplotype diversity (Hd) was high (0.91-1.00), and nucleotide diversity (π) was low (0.002-0.009), which suggests a population bottleneck followed by rapid population growth. Based on the phylogenetic trees, minimum spanning network (MSN), population pairwise comparison, and F ST,and supported by analysis of molecular variance (AMOVA) and spatial analysis of molecular variance (SAMOVA) tests, distinct genetic structures were observed (7.2% to 7.6% genetic divergence) between populations in the SCS and its neighboring waters, versus those in the AS. Furthermore, the results defined A. sirm stock boundaries and evolutionary between the west and east coast (which shares the same waters as western Borneo) of Peninsular Malaysia. In addition, genetic homogeneity was revealed throughout the SCS, SS, and CS based on the non-significant F STpairwise comparisons. Based on the molecular evidence, separate management strategies may be required for A. sirm of the AS and the SCS, including its neighboring waters.
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Affiliation(s)
- Noorul Azliana Jamaludin
- Centre for Global Sustainability Studies (CGSS), Universiti Sains Malaysia, Penang, Malaysia,Marine Capture Fisheries Division, Fisheries Research Institute, Sitiawan, Perak, Malaysia
| | | | | | - Noor Adelyna Mohammed Akib
- Centre for Global Sustainability Studies (CGSS), Universiti Sains Malaysia, Penang, Malaysia,School of Biology, Universiti Sains Malaysia, Penang, Malaysia
| | - Sahat Ratmuangkhwang
- Andaman Coastal Research Station for Development, Kasetsart University, Ranong, Thailand
| | - Wahidah Mohd Arshaad
- Southeast Asia Fisheries Development Center (SEAFDEC), Marine Fisheries Resources Development and Management Department (MFRDMD), Kuala Terengganu, Terengganu, Malaysia
| | - Siti Azizah Mohd Nor
- Institute of Marine Biotechnology, Universiti Malaysia Terengganu, Kuala Terengganu, Terengganu, Malaysia
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6
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Canfield SJ, Galván-Magaña F, Bowen BW. Little Sharks in a Big World: Mitochondrial DNA Reveals Small-scale Population Structure in the California Horn Shark (Heterodontus francisci). J Hered 2022; 113:298-310. [PMID: 35438775 DOI: 10.1093/jhered/esac008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 02/22/2022] [Indexed: 11/13/2022] Open
Abstract
The California horn shark (Heterodontus francisci) is a small demersal species distributed from southern California and the Channel Islands to Baja California and the Gulf of California. These nocturnal reef predators maintain small home-ranges as adults, and lay auger-shaped egg cases that become wedged into the substrate. While population trends are not well documented, this species is subject to fishing pressure through portions of its range and has been identified as vulnerable to overexploitation. Here we present a survey of 318 specimens from across the range, using mtDNA control region sequences to provide the first genetic assessment of H. francisci. Overall population structure (ΦST = 0.266, P < 0.001) is consistent with limited dispersal as indicated by life history, with two distinct features. Population structure along the continuous coastline is low, with no discernable breaks from Santa Barbara, CA to Bahia Tortugas (Baja California Sur, Mexico); however, there is a notable partition at Punta Eugenia (BCS), a well-known biogeographic break between tropical and subtropical marine faunas. In contrast, population structure is much higher (max ΦST = 0.601, P < 0.05) between the coast and adjacent Channel Islands, a minimum distance of 19 km, indicating that horn sharks rarely disperse across deep habitat and open water. Population structure in most elasmobranchs is measured on a scale of hundreds to thousands of kilometers, but the California Horn Shark has population partitions on an unprecedented small scale, indicating a need for localized management strategies which ensure adequate protection of distinct stocks.
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Affiliation(s)
- Sean J Canfield
- School of Life Sciences, University of Hawai'i at Mānoa, Honolulu, HI, USA.,Hawai'i Institute of Marine Biology, University of Hawai'i at Mānoa, Kaneohe, HI, USA
| | - Felipe Galván-Magaña
- Instituto Politécnico Nacional, Centro Interdisciplinario de Ciencias Marinas, La Paz, Baja California Sur, México
| | - Brian W Bowen
- Hawai'i Institute of Marine Biology, University of Hawai'i at Mānoa, Kaneohe, HI, USA
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7
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Genomic insights into the historical and contemporary demographics of the grey reef shark. Heredity (Edinb) 2022; 128:225-235. [PMID: 35296830 PMCID: PMC8987070 DOI: 10.1038/s41437-022-00514-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 02/11/2022] [Accepted: 02/13/2022] [Indexed: 11/08/2022] Open
Abstract
Analyses of genetic diversity can shed light on both the origins of biodiversity hotspots, as well as the conservation status of species that are impacted by human activities. With these objectives, we assembled a genomic dataset of 14,935 single nucleotide polymorphisms from 513 grey reef sharks (Carcharhinus amblyrhynchos) sampled across 17 locations in the tropical Indo-Pacific. We analysed geographic variation in genetic diversity, estimated ancient and contemporary effective population size (Ne) across sampling locations (using coalescent and linkage disequilibrium methods) and modelled the history of gene flow between the Coral Triangle and the Coral Sea. Genetic diversity decreased with distance away from the Coral Triangle and north-western Australia, implying that C. amblyrhynchos may have originated in this region. Increases in Ne were detected across almost all sampling locations 40,000-90,000 generations ago (approximately 0.6-1.5 mya, given an estimated generation time of 16.4 years), suggesting a range expansion around this time. More recent, secondary increases in Ne were inferred for the Misool and North Great Barrier Reef sampling locations, but joint modelling did not clarify whether these were due to population growth, migration, or both. Despite the greater genetic diversity and ancient Ne observed at sites around Australia and the Coral Triangle, remote reefs around north-western New Caledonia had the highest contemporary Ne, demonstrating the importance of using multiple population size assessment methods. This study provides insight into both the past and present demographics of C. amblyrhynchos and contributes to our understanding of evolution in marine biodiversity hotspots.
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Pratt EAL, Beheregaray LB, Bilgmann K, Zanardo N, Diaz-Aguirre F, Brauer C, Sandoval-Castillo J, Möller LM. Seascape genomics of coastal bottlenose dolphins along strong gradients of temperature and salinity. Mol Ecol 2022; 31:2223-2241. [PMID: 35146819 DOI: 10.1111/mec.16389] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 02/01/2022] [Accepted: 02/03/2022] [Indexed: 11/30/2022]
Abstract
Heterogeneous seascapes and strong environmental gradients in coastal waters are expected to influence adaptive divergence, particularly in species with large population sizes where selection is expected to be highly efficient. However, these influences might also extend to species characterized by strong social structure, natal philopatry and small home ranges. We implemented a seascape genomic study to test this hypothesis in Indo-Pacific bottlenose dolphins (Tursiops aduncus) distributed along the environmentally heterogeneous coast of southern Australia. The datasets included oceanographic and environmental variables thought to be good predictors of local adaptation in dolphins and 8,081 filtered single nucleotide polymorphisms (SNPs) genotyped for individuals sampled from seven different bioregions. From a neutral perspective, population structure and connectivity of the dolphins were generally influenced by habitat type and social structuring. Genotype-environment association analysis identified 241 candidate adaptive loci and revealed that sea surface temperature and salinity gradients influenced adaptive divergence in these animals at both large- (1,000s km) and fine-scales (<100 km). Enrichment analysis and annotation of candidate genes revealed functions related to sodium-activated ion transport, kidney development, adipogenesis and thermogenesis. The findings of spatial adaptive divergence and inferences of putative physiological adaptations challenge previous suggestions that marine megafauna is most likely to be affected by environmental and climatic changes via indirect, trophic effects. Our work contributes to conservation management of coastal bottlenose dolphins subjected to anthropogenic disturbance and to efforts of clarifying how seascape heterogeneity influences adaptive diversity and evolution in small cetaceans.
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Affiliation(s)
- Eleanor A L Pratt
- Molecular Ecology Laboratory, College of Science and Engineering, Flinders University, Bedford Park, 5042, South Australia, Australia.,Cetacean Ecology, Behaviour and Evolution Laboratory, College of Science and Engineering, Flinders University, Bedford Park, 5042, South Australia, Australia
| | - Luciano B Beheregaray
- Molecular Ecology Laboratory, College of Science and Engineering, Flinders University, Bedford Park, 5042, South Australia, Australia
| | - Kerstin Bilgmann
- Department of Biological Sciences, Macquarie University, 2109, New South Wales, Australia
| | - Nikki Zanardo
- Molecular Ecology Laboratory, College of Science and Engineering, Flinders University, Bedford Park, 5042, South Australia, Australia.,Cetacean Ecology, Behaviour and Evolution Laboratory, College of Science and Engineering, Flinders University, Bedford Park, 5042, South Australia, Australia.,Department of Environment and Water, Adelaide, 5000, South Australia, Australia
| | - Fernando Diaz-Aguirre
- Molecular Ecology Laboratory, College of Science and Engineering, Flinders University, Bedford Park, 5042, South Australia, Australia.,Cetacean Ecology, Behaviour and Evolution Laboratory, College of Science and Engineering, Flinders University, Bedford Park, 5042, South Australia, Australia
| | - Chris Brauer
- Molecular Ecology Laboratory, College of Science and Engineering, Flinders University, Bedford Park, 5042, South Australia, Australia
| | - Jonathan Sandoval-Castillo
- Molecular Ecology Laboratory, College of Science and Engineering, Flinders University, Bedford Park, 5042, South Australia, Australia
| | - Luciana M Möller
- Molecular Ecology Laboratory, College of Science and Engineering, Flinders University, Bedford Park, 5042, South Australia, Australia.,Cetacean Ecology, Behaviour and Evolution Laboratory, College of Science and Engineering, Flinders University, Bedford Park, 5042, South Australia, Australia
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Brown banded bamboo shark (Chiloscyllium punctatum) shows high genetic diversity and differentiation in Malaysian waters. Sci Rep 2021; 11:14874. [PMID: 34290296 PMCID: PMC8295251 DOI: 10.1038/s41598-021-94257-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 07/07/2021] [Indexed: 02/06/2023] Open
Abstract
The demersal brown banded bamboo shark Chiloscyllium punctatum is a major component of sharks landed in Malaysia. However, little is known about their population structure and the effect of high fishing pressure on these weak swimming sharks. Both mitochondrial DNA control region (1072 bp) and NADH dehydrogenase subunit 2 (1044 bp) were used to elucidate the genetic structure and connectivity of C. punctatum among five major areas within the Sundaland region. Our findings revealed (i) strong genetic structure with little present day mixing between the major areas, (ii) high intra-population genetic diversity with unique haplotypes, (iii) significant correlation between genetic differentiation and geographical distance coupled with detectable presence of fine scale geographical barriers (i.e. the South China Sea), (iv) historical directional gene flow from the east coast of Peninsular Malaysia towards the west coast and Borneo, and (v) no detectable genetic differentiation along the coastline of east Peninsular Malaysia. Genetic patterns inferred from the mitochondrial DNA loci were consistent with the strong coastal shelf association in this species, the presence of contemporary barriers shaped by benthic features, and limited current-driven egg dispersal. Fine scale population structure of C. punctatum highlights the need to improve genetic understanding for fishery management and conservation of other small-sized sharks.
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Pirog A, Ravigné V, Fontaine MC, Rieux A, Gilabert A, Cliff G, Clua E, Daly R, Heithaus MR, Kiszka JJ, Matich P, Nevill JEG, Smoothey AF, Temple AJ, Berggren P, Jaquemet S, Magalon H. Population structure, connectivity, and demographic history of an apex marine predator, the bull shark Carcharhinus leucas. Ecol Evol 2019; 9:12980-13000. [PMID: 31871624 PMCID: PMC6912899 DOI: 10.1002/ece3.5597] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 07/23/2019] [Accepted: 07/28/2019] [Indexed: 01/16/2023] Open
Abstract
Knowledge of population structure, connectivity, and effective population size remains limited for many marine apex predators, including the bull shark Carcharhinus leucas. This large-bodied coastal shark is distributed worldwide in warm temperate and tropical waters, and uses estuaries and rivers as nurseries. As an apex predator, the bull shark likely plays a vital ecological role within marine food webs, but is at risk due to inshore habitat degradation and various fishing pressures. We investigated the bull shark's global population structure and demographic history by analyzing the genetic diversity of 370 individuals from 11 different locations using 25 microsatellite loci and three mitochondrial genes (CR, nd4, and cytb). Both types of markers revealed clustering between sharks from the Western Atlantic and those from the Western Pacific and the Western Indian Ocean, with no contemporary gene flow. Microsatellite data suggested low differentiation between the Western Indian Ocean and the Western Pacific, but substantial differentiation was found using mitochondrial DNA. Integrating information from both types of markers and using Bayesian computation with a random forest procedure (ABC-RF), this discordance was found to be due to a complete lack of contemporary gene flow. High genetic connectivity was found both within the Western Indian Ocean and within the Western Pacific. In conclusion, these results suggest important structuring of bull shark populations globally with important gene flow occurring along coastlines, highlighting the need for management and conservation plans on regional scales rather than oceanic basin scale.
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Affiliation(s)
- Agathe Pirog
- UMR ENTROPIE (Université de La Réunion/IRD/CNRS)Université de La RéunionSaint DenisFrance
| | | | - Michaël C. Fontaine
- Laboratoire MIVEGEC (Université de Montpellier UMR CNRS 5290, IRD 229)Centre IRD de MontpellierMontpellierFrance
- Groningen Institute for Evolutionary Life Sciences (GELIFES)University of GroningenGroningenThe Netherlands
| | | | | | - Geremy Cliff
- KwaZulu‐Natal Sharks BoardUmhlanga RocksSouth Africa
- School of Life SciencesUniversity of KwaZulu‐NatalDurbanSouth Africa
| | - Eric Clua
- EPHECNRS UPVDUSR 3278 CRIOBEPSL Research UniversityPerpignanFrance
- Laboratoire d'Excellence CORAILPerpignanFrance
| | - Ryan Daly
- Oceanographic Research InstituteDurbanSouth Africa
- South African Institute for Aquatic BiodiversityGrahamstownSouth Africa
| | - Michael R. Heithaus
- Department of Biological SciencesFlorida International UniversityNorth MiamiFLUSA
| | - Jeremy J. Kiszka
- Department of Biological SciencesFlorida International UniversityNorth MiamiFLUSA
| | - Philip Matich
- Department of Biological SciencesFlorida International UniversityNorth MiamiFLUSA
| | | | - Amy F. Smoothey
- NSW Department of Primary IndustriesSydney Institute of Marine ScienceMosmanNSWAustralia
| | - Andrew J. Temple
- School of Natural and Environmental SciencesNewcastle UniversityNewcastle‐upon‐TyneUK
| | - Per Berggren
- School of Natural and Environmental SciencesNewcastle UniversityNewcastle‐upon‐TyneUK
| | - Sébastien Jaquemet
- UMR ENTROPIE (Université de La Réunion/IRD/CNRS)Université de La RéunionSaint DenisFrance
| | - Hélène Magalon
- UMR ENTROPIE (Université de La Réunion/IRD/CNRS)Université de La RéunionSaint DenisFrance
- Laboratoire d'Excellence CORAILPerpignanFrance
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11
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Dahl RB, Sigsgaard EE, Mwangi G, Thomsen PF, Jørgensen RD, Torquato FDO, Olsen L, Møller PR. The Sandy Zebra Shark: A New Color Morph of the Zebra Shark Stegostoma tigrinum, with a Redescription of the Species and a Revision of Its Nomenclature. COPEIA 2019. [DOI: 10.1643/cg-18-115] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Affiliation(s)
- Rikke Beckmann Dahl
- Natural History Museum of Denmark, University of Copenhagen, Universitetsparken 15, 2100 Copenhagen, Denmark; (RBD) rikke. ; (FOT) ; and (PRM) . Send reprint requests to RBD
| | - Eva Egelyng Sigsgaard
- Department of Bioscience, University of Aarhus, Ny Munkegade 116, Building 1540, 8000 Aarhus C, Denmark; (EES) ; and (PFT)
| | - Gorret Mwangi
- Kenya Tropical Sealife Ltd, P.O Box 10570-80101, Bamburi, Kenya; (GM) ; and (RDJ)
| | - Philip Francis Thomsen
- Department of Bioscience, University of Aarhus, Ny Munkegade 116, Building 1540, 8000 Aarhus C, Denmark; (EES) ; and (PFT)
| | | | - Felipe de Oliveira Torquato
- Natural History Museum of Denmark, University of Copenhagen, Universitetsparken 15, 2100 Copenhagen, Denmark; (RBD) rikke. ; (FOT) ; and (PRM) . Send reprint requests to RBD
| | - Lars Olsen
- Danish National Aquarium (Den Blå Planet) Jacob Fortlingsvej 1, 2770 Kastrup, Denmark;
| | - Peter Rask Møller
- Natural History Museum of Denmark, University of Copenhagen, Universitetsparken 15, 2100 Copenhagen, Denmark; (RBD) rikke. ; (FOT) ; and (PRM) . Send reprint requests to RBD
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Corrigan S, Lowther AD, Beheregaray LB, Bruce BD, Cliff G, Duffy CA, Foulis A, Francis MP, Goldsworthy SD, Hyde JR, Jabado RW, Kacev D, Marshall L, Mucientes GR, Naylor GJP, Pepperell JG, Queiroz N, White WT, Wintner SP, Rogers PJ. Population Connectivity of the Highly Migratory Shortfin Mako (Isurus oxyrinchus Rafinesque 1810) and Implications for Management in the Southern Hemisphere. Front Ecol Evol 2018. [DOI: 10.3389/fevo.2018.00187] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Larson SE, Daly-Engel TS, Phillips NM. Review of Current Conservation Genetic Analyses of Northeast Pacific Sharks. ADVANCES IN MARINE BIOLOGY 2017; 77:79-110. [PMID: 28882215 DOI: 10.1016/bs.amb.2017.06.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Conservation genetics is an applied science that utilizes molecular tools to help solve problems in species conservation and management. It is an interdisciplinary specialty in which scientists apply the study of genetics in conjunction with traditional ecological fieldwork and other techniques to explore molecular variation, population boundaries, and evolutionary relationships with the goal of enabling resource managers to better protect biodiversity and identify unique populations. Several shark species in the northeast Pacific (NEP) have been studied using conservation genetics techniques, which are discussed here. The primary methods employed to study population genetics of sharks have historically been nuclear microsatellites and mitochondrial (mt) DNA. These markers have been used to assess genetic diversity, mating systems, parentage, relatedness, and genetically distinct populations to inform management decisions. Novel approaches in conservation genetics, including next-generation DNA and RNA sequencing, environmental DNA (eDNA), and epigenetics are just beginning to be applied to elasmobranch evolution, physiology, and ecology. Here, we review the methods and results of past studies, explore future directions for shark conservation genetics, and discuss the implications of molecular research and techniques for the long-term management of shark populations in the NEP.
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Affiliation(s)
| | | | - Nicole M Phillips
- The University of Southern Mississippi, Hattiesburg, MS, United States
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Switch from sexual to parthenogenetic reproduction in a zebra shark. Sci Rep 2017; 7:40537. [PMID: 28091617 PMCID: PMC5238396 DOI: 10.1038/srep40537] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Accepted: 11/28/2016] [Indexed: 11/08/2022] Open
Abstract
Parthenogenesis is a natural form of asexual reproduction in which embryos develop in the absence of fertilisation. Most commonly found in plants and invertebrate organisms, an increasing number of vertebrate species have recently been reported employing this reproductive strategy. Here we use DNA genotyping to report the first demonstration of an intra-individual switch from sexual to parthenogenetic reproduction in a shark species, the zebra shark Stegostoma fasciatum. A co-housed, sexually produced daughter zebra shark also commenced parthenogenetic reproduction at the onset of maturity without any prior mating. The demonstration of parthenogenesis in these two conspecific individuals with different sexual histories provides further support that elasmobranch fishes may flexibly adapt their reproductive strategy to environmental circumstances.
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Bernard AM, Feldheim KA, Heithaus MR, Wintner SP, Wetherbee BM, Shivji MS. Global population genetic dynamics of a highly migratory, apex predator shark. Mol Ecol 2016; 25:5312-5329. [DOI: 10.1111/mec.13845] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Revised: 08/09/2016] [Accepted: 08/25/2016] [Indexed: 01/19/2023]
Affiliation(s)
- Andrea M. Bernard
- Save Our Seas Shark Research Center Halmos College of Natural Sciences & Oceanography Nova Southeastern University 8000 N. Ocean Drive Dania Beach FL 33004 USA
| | - Kevin A. Feldheim
- The Field Museum of Natural History Pritzker Laboratory for Molecular Systematics and Evolution 1400 South Lake Shore Drive Chicago IL 60605 USA
| | - Michael R. Heithaus
- School of Environment and Society Florida International University Miami FL USA
| | - Sabine P. Wintner
- KwaZulu‐Natal Sharks Board Private Bag 2 Umhlanga Rocks 4320 South Africa
- Biomedical Resource Unit University of KwaZulu‐Natal Durban 4000 South Africa
| | - Bradley M. Wetherbee
- Department of Biological Sciences University of Rhode Island Kingston RI USA
- Guy Harvey Research Institute Dania Beach, FL 33004 USA
| | - Mahmood S. Shivji
- Save Our Seas Shark Research Center and Guy Harvey Research Institute Halmos College of Natural Sciences & Oceanography Nova Southeastern University 8000 N. Ocean Drive Dania Beach FL 33004 USA
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Díaz-Jaimes P, Bayona-Vásquez NJ, Adams DH, Uribe-Alcocer M. Complete mitochondrial DNA genome of bonnethead shark, Sphyrna tiburo, and phylogenetic relationships among main superorders of modern elasmobranchs. Meta Gene 2016; 7:48-55. [PMID: 27014583 PMCID: PMC4794228 DOI: 10.1016/j.mgene.2015.11.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Revised: 11/18/2015] [Accepted: 11/19/2015] [Indexed: 11/30/2022] Open
Abstract
Elasmobranchs are one of the most diverse groups in the marine realm represented by 18 orders, 55 families and about 1200 species reported, but also one of the most vulnerable to exploitation and to climate change. Phylogenetic relationships among main orders have been controversial since the emergence of the Hypnosqualean hypothesis by Shirai (1992) that considered batoids as a sister group of sharks. The use of the complete mitochondrial DNA (mtDNA) may shed light to further validate this hypothesis by increasing the number of informative characters. We report the mtDNA genome of the bonnethead shark Sphyrna tiburo, and compare it with mitogenomes of other 48 species to assess phylogenetic relationships. The mtDNA genome of S. tiburo, is quite similar in size to that of congeneric species but also similar to the reported mtDNA genome of other Carcharhinidae species. Like most vertebrate mitochondrial genomes, it contained 13 protein coding genes, two rRNA genes and 22 tRNA genes and the control region of 1086 bp (D-loop). The Bayesian analysis of the 49 mitogenomes supported the view that sharks and batoids are separate groups.
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Key Words
- ATP, Adenosine triphosphate
- Bonnethead
- CO, Cytochrome oxidase
- Cytb, Cytochrome B
- D-loop, Control region
- Hypnosqualea hypothesis
- ML, Maximum likelihood
- Mitogenome
- ND, Nicotine adenine dehydrogenase
- PCR, Polymerase chain reaction
- Phylogeny
- bp, Base pairs
- mt, Mitochondrial
- myr, Million years
- rRNA, Ribosomal RNA
- tRNA, Transference RNA
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Affiliation(s)
- Píndaro Díaz-Jaimes
- Laboratorio de Genética de Organismos Acuáticos, Instituto de
Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Apdo.
Postal 70-305, México D.F. 04510, Mexico
| | - Natalia J. Bayona-Vásquez
- Laboratorio de Genética de Organismos Acuáticos, Instituto de
Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Apdo.
Postal 70-305, México D.F. 04510, Mexico
| | - Douglas H. Adams
- Florida Fish and Wildlife Conservation Commission, Fish and
Wildlife Research Institute, 1220 Prospect Avenue, Suite 285, Melbourne, FL
32901, USA
| | - Manuel Uribe-Alcocer
- Laboratorio de Genética de Organismos Acuáticos, Instituto de
Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Apdo.
Postal 70-305, México D.F. 04510, Mexico
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Osgood GJ, Baum JK. Reef sharks: recent advances in ecological understanding to inform conservation. JOURNAL OF FISH BIOLOGY 2015; 87:1489-1523. [PMID: 26709218 DOI: 10.1111/jfb.12839] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 10/09/2015] [Indexed: 06/05/2023]
Abstract
Sharks are increasingly being recognized as important members of coral-reef communities, but their overall conservation status remains uncertain. Nine of the 29 reef-shark species are designated as data deficient in the IUCN Red List, and three-fourths of reef sharks had unknown population trends at the time of their assessment. Fortunately, reef-shark research is on the rise. This new body of research demonstrates reef sharks' high site restriction, fidelity and residency on coral reefs, their broad trophic roles connecting reef communities and their high population genetic structure, all information that should be useful for their management and conservation. Importantly, recent studies on the abundance and population trends of the three classic carcharhinid reef sharks (grey reef shark Carcharhinus amblyrhynchos, blacktip reef shark Carcharhinus melanopterus and whitetip reef shark Triaenodon obesus) may contribute to reassessments identifying them as more vulnerable than currently realized. Because over half of the research effort has focused on only these three reef sharks and the nurse shark Ginglymostoma cirratum in only a few locales, there remain large taxonomic and geographic gaps in reef-shark knowledge. As such, a large portion of reef-shark biodiversity remains uncharacterized despite needs for targeted research identified in their red list assessments. A research agenda for the future should integrate abundance, life history, trophic ecology, genetics, habitat use and movement studies, and expand the breadth of such research to understudied species and localities, in order to better understand the conservation requirements of these species and to motivate effective conservation solutions.
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Affiliation(s)
- G J Osgood
- Department of Biology, University of Victoria, P. O. Box 1700 STN CSC, Victoria, BC V8W 2Y2, Canada
| | - J K Baum
- Department of Biology, University of Victoria, P. O. Box 1700 STN CSC, Victoria, BC V8W 2Y2, Canada
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Gledhill KS, Kessel ST, Guttridge TL, Hansell AC, Bester-van der Merwe AE, Feldheim KA, Gruber SH, Chapman DD. Genetic structure, population demography and seasonal occurrence of blacktip shark Carcharhinus limbatus in Bimini, the Bahamas. JOURNAL OF FISH BIOLOGY 2015; 87:1371-1388. [PMID: 26709212 DOI: 10.1111/jfb.12821] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2015] [Accepted: 09/18/2015] [Indexed: 06/05/2023]
Abstract
A longline survey was conducted from 2004 to 2014 to investigate the demographic population structure and seasonal abundance of the blacktip shark Carcharhinus limbatus in the Bimini Islands, the Bahamas. All individuals sampled (n = 242) were sub-adult or adults [70·1-145·1 cm pre-caudal length (LPC) range] with no neonates or YOY recorded in Bimini. Carcharhinus limbatus abundance peaked in September, coincident with the largest ratio of female to male sharks and a peak in fresh mating wounds on females. Mitochondrial control region (mtCR) DNA sequences were obtained from C. limbatus at Bimini to test whether Bimini C. limbatus are most closely related to geographically proximate populations sampled on the south-eastern coast of the U.S.A., the closest known nursery areas for this species. Nine mtCR haplotypes were observed in 32 individuals sampled at Bimini [haplotype diversity (h) = 0·821, nucleotide diversity (π) = 0·0015]. Four haplotypes observed from Bimini matched those previously found in the northern Yucatan (Mexico)-Belize and two matched a haplotype previously found in the U.S.A. Four haplotypes were novel but were closely related to the northern Yucatan-Belizean haplotypes. Pair-wise ΦST analysis showed that Bimini was significantly differentiated from all of the populations previously sampled (U.S.A. Atlantic, U.S.A. Gulf of Mexico, northern Yucatan, Belize and Brazil). This indicates that C. limbatus sampled from Bimini are unlikely from the described, proximate U.S.A. nurseries.
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Affiliation(s)
- K S Gledhill
- South African Shark Conservancy, Old Harbour Museum, Hermanus 7200, South Africa
| | - S T Kessel
- Great Lakes Institute for Environmental Research, University of Windsor, Windsor, ON N9B 3P4, Canada
| | - T L Guttridge
- Bimini Biological Field Station Foundation, 15 Elizabeth Drive, South Bimini, Bahamas
| | - A C Hansell
- Department of Fisheries Oceanography, School for Marine Science and Technology, University of Massachusetts - Dartmouth, Fairhaven, MA 02719, U.S.A
| | - A E Bester-van der Merwe
- Molecular Breeding and Biodiversity Group, Department of Genetics, Stellenbosch University, Stellenbosch 7600, South Africa
| | - K A Feldheim
- Pritzker Laboratory for Molecular Systematics and Evolution, Field Museum of Natural History, 1400 South Lake Shore Drive, Chicago, IL 60605, U.S.A
| | - S H Gruber
- Bimini Biological Field Station Foundation, 15 Elizabeth Drive, South Bimini, Bahamas
- Rosenstiel School of Marine and Atmospheric Sciences, University of Miami, Miami, FL 33124, U.S.A
| | - D D Chapman
- Institute for Ocean Conservation Science/School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, NY 11794-5000, U.S.A
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20
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Bester-van der Merwe AE, Gledhill KS. Molecular species identification and population genetics of chondrichthyans in South Africa: current challenges, priorities and progress. AFRICAN ZOOLOGY 2015. [DOI: 10.1080/15627020.2015.1063408] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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21
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The relationship between abundance and genetic effective population size in elasmobranchs: an example from the globally threatened zebra shark Stegostoma fasciatum within its protected range. CONSERV GENET 2015. [DOI: 10.1007/s10592-015-0752-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Spaet JLY, Jabado RW, Henderson AC, Moore ABM, Berumen ML. Population genetics of four heavily exploited shark species around the Arabian Peninsula. Ecol Evol 2015; 5:2317-32. [PMID: 26120422 PMCID: PMC4475365 DOI: 10.1002/ece3.1515] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Revised: 04/22/2015] [Accepted: 04/23/2015] [Indexed: 01/31/2023] Open
Abstract
The northwestern Indian Ocean harbors a number of larger marine vertebrate taxa that warrant the investigation of genetic population structure given remarkable spatial heterogeneity in biological characteristics such as distribution, behavior, and morphology. Here, we investigate the genetic population structure of four commercially exploited shark species with different biological characteristics (Carcharhinus limbatus, Carcharhinus sorrah, Rhizoprionodon acutus, and Sphyrna lewini) between the Red Sea and all other water bodies surrounding the Arabian Peninsula. To assess intraspecific patterns of connectivity, we constructed statistical parsimony networks among haplotypes and estimated (1) population structure; and (2) time of most recent population expansion, based on mitochondrial control region DNA and a total of 20 microsatellites. Our analysis indicates that, even in smaller, less vagile shark species, there are no contemporary barriers to gene flow across the study region, while historical events, for example, Pleistocene glacial cycles, may have affected connectivity in C. sorrah and R. acutus. A parsimony network analysis provided evidence that Arabian S. lewini may represent a population segment that is distinct from other known stocks in the Indian Ocean, raising a new layer of conservation concern. Our results call for urgent regional cooperation to ensure the sustainable exploitation of sharks in the Arabian region.
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Affiliation(s)
- Julia L Y Spaet
- Red Sea Research Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology23955-6900, Thuwal, Saudi Arabia
| | - Rima W Jabado
- Gulf Elasmo ProjectP.O. Box 29588, Dubai, United Arab Emirates
| | - Aaron C Henderson
- Department of Marine Science & Fisheries, College of Agricultural & Marine Sciences, Sultan Qaboos UniversityMuscat, Oman
| | - Alec B M Moore
- RSK Environment Ltd, Spring LodgeHelsby, Cheshire, WA6 0AR, UK
| | - Michael L Berumen
- Red Sea Research Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology23955-6900, Thuwal, Saudi Arabia
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White WT. Species composition and aspects of the biology of Orectolobiformes from Indonesian waters. JOURNAL OF FISH BIOLOGY 2015; 86:484-492. [PMID: 25546571 DOI: 10.1111/jfb.12569] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Accepted: 09/28/2014] [Indexed: 06/04/2023]
Abstract
The biological aspects of members of the order Orectolobiformes exploited in Indonesian waters are given. Seven species belonging to five families were recorded in the catches at various landing sites in southern Indonesia. Of these, Chiloscyllium punctatum was the most abundant species landed, contributing >50% of the number of orectolobiforms recorded. The biological data obtained varied greatly between the species listed. The total length (LT ) at maturity for some species, e.g. C. punctatum and Nebrius ferrugineus, varied from that which has been previously recorded for those species in other regions. This highlights the need for regional-specific biological data for fisheries managers and conservation assessors.
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Affiliation(s)
- W T White
- CSIRO Oceans & Atmosphere Flagship, G. P. O. Box 1538, Hobart TAS 7001, Australia
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Mitogenomics of the Speartooth Shark challenges ten years of control region sequencing. BMC Evol Biol 2014; 14:232. [PMID: 25406508 PMCID: PMC4245800 DOI: 10.1186/s12862-014-0232-x] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Accepted: 11/04/2014] [Indexed: 11/23/2022] Open
Abstract
Background Mitochondrial DNA markers have long been used to identify population boundaries and are now a standard tool in conservation biology. In elasmobranchs, evolutionary rates of mitochondrial genes are low and variation between distinct populations can be hard to detect with commonly used control region sequencing or other single gene approaches. In this study we sequenced the whole mitogenome of 93 Critically Endangered Speartooth Shark Glyphis glyphis from the last three river drainages they inhabit in northern Australia. Results Genetic diversity was extremely low (π =0.00019) but sufficient to demonstrate the existence of barriers to gene flow among river drainages (AMOVA ΦST =0.28283, P <0.00001). Surprisingly, the comparison with single gene sub-datasets revealed that ND5 and 12S were the only ones carrying enough information to detect similar levels of genetic structure. The control region exhibited only one mutation, which was not sufficient to detect any structure among river drainages. Conclusions This study strongly supports the use of single river drainages as discrete management units for the conservation of G. glyphis. Furthermore when genetic diversity is low, as is often the case in elasmobranchs, our results demonstrate a clear advantage of using the whole mitogenome to inform population structure compared to single gene approaches. More specifically, this study questions the extensive use of the control region as the preferential marker for elasmobranch population genetic studies and whole mitogenome sequencing will probably uncover a large amount of cryptic population structure in future studies. Electronic supplementary material The online version of this article (doi:10.1186/s12862-014-0232-x) contains supplementary material, which is available to authorized users.
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Geraghty PT, Williamson JE, Macbeth WG, Blower DC, Morgan JAT, Johnson G, Ovenden JR, Gillings MR. Genetic structure and diversity of two highly vulnerable carcharhinids in Australian waters. ENDANGER SPECIES RES 2014. [DOI: 10.3354/esr00580] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Marranzino A. The use of positive reinforcement in training zebra sharks (Stegostoma fasciatum). J APPL ANIM WELF SCI 2014; 16:239-53. [PMID: 23795687 DOI: 10.1080/10888705.2013.798555] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Positive reinforcement training (PRT) was used on 4 adult zebra sharks, Stegostoma fasciatum, housed at the Downtown Aquarium, Denver, to determine the ability of zebra sharks to become desensitized to various stimuli associated with veterinary procedures. One male and 3 female sharks were trained for 12 weeks. As a result of PRT, all 4 zebra sharks were desensitized to staying within a closed holding tank off of the main exhibit, the presence of multiple trainers in the closed holding tank, and tactile stimulation. One of the 4 zebra sharks was also successfully desensitized to the presence of a stretcher being brought into the holding tank. All of these procedures are common in veterinary examinations, and it is hoped that desensitization to these stimuli will reduce the stress associated with examinations. The training accomplished has allowed for easier maintenance of the zebra sharks by the aquarium staff and an improvement in the care of the sharks.
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Castillo-Páez A, Sosa-Nishizaki O, Sandoval-Castillo J, Galván-Magaña F, Blanco-Parra MDP, Rocha-Olivares A. Strong Population Structure and Shallow Mitochondrial Phylogeny in the Banded Guitarfish, Zapteryx exasperata (Jordan y Gilbert, 1880), from the Northern Mexican Pacific. J Hered 2013; 105:91-100. [DOI: 10.1093/jhered/est067] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Geraghty PT, Williamson JE, Macbeth WG, Wintner SP, Harry AV, Ovenden JR, Gillings MR. Population expansion and genetic structure in Carcharhinus brevipinna in the southern Indo-Pacific. PLoS One 2013; 8:e75169. [PMID: 24086462 PMCID: PMC3783459 DOI: 10.1371/journal.pone.0075169] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Accepted: 08/12/2013] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Quantifying genetic diversity and metapopulation structure provides insights into the evolutionary history of a species and helps develop appropriate management strategies. We provide the first assessment of genetic structure in spinner sharks (Carcharhinus brevipinna), a large cosmopolitan carcharhinid, sampled from eastern and northern Australia and South Africa. METHODS AND FINDINGS Sequencing of the mitochondrial DNA NADH dehydrogenase subunit 4 gene for 430 individuals revealed 37 haplotypes and moderately high haplotype diversity (h = 0.6770 ±0.025). While two metrics of genetic divergence (ΦST and F ST) revealed somewhat different results, subdivision was detected between South Africa and all Australian locations (pairwise ΦST, range 0.02717-0.03508, p values ≤ 0.0013; pairwise F ST South Africa vs New South Wales = 0.04056, p = 0.0008). Evidence for fine-scale genetic structuring was also detected along Australia's east coast (pairwise ΦST = 0.01328, p < 0.015), and between south-eastern and northern locations (pairwise ΦST = 0.00669, p < 0.04). CONCLUSIONS The Indian Ocean represents a robust barrier to contemporary gene flow in C. brevipinna between Australia and South Africa. Gene flow also appears restricted along a continuous continental margin in this species, with data tentatively suggesting the delineation of two management units within Australian waters. Further sampling, however, is required for a more robust evaluation of the latter finding. Evidence indicates that all sampled populations were shaped by a substantial demographic expansion event, with the resultant high genetic diversity being cause for optimism when considering conservation of this commercially-targeted species in the southern Indo-Pacific.
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Affiliation(s)
- Pascal T. Geraghty
- Department of Biological Sciences, Macquarie University, Sydney, New South Wales, Australia
- Cronulla Fisheries Research Centre of Excellence, New South Wales Department of Primary Industries, Sydney, New South Wales, Australia
| | - Jane E. Williamson
- Department of Biological Sciences, Macquarie University, Sydney, New South Wales, Australia
| | - William G. Macbeth
- Cronulla Fisheries Research Centre of Excellence, New South Wales Department of Primary Industries, Sydney, New South Wales, Australia
| | - Sabine P. Wintner
- KwaZulu-Natal Sharks Board, Umhlanga Rocks, KwaZulu-Natal, South Africa
| | - Alastair V. Harry
- Centre for Sustainable Tropical Fisheries and Aquaculture, James Cook University, Townsville, Queensland, Australia
| | - Jennifer R. Ovenden
- Molecular Fisheries Laboratory, the University of Queensland, St. Lucia, Queensland, Australia
| | - Michael R. Gillings
- Department of Biological Sciences, Macquarie University, Sydney, New South Wales, Australia
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Puckridge M, Last PR, White WT, Andreakis N. Phylogeography of the Indo-West Pacific maskrays (Dasyatidae, Neotrygon): a complex example of chondrichthyan radiation in the Cenozoic. Ecol Evol 2012; 3:217-32. [PMID: 23467194 PMCID: PMC3586632 DOI: 10.1002/ece3.448] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2012] [Revised: 11/14/2012] [Accepted: 11/15/2012] [Indexed: 12/03/2022] Open
Abstract
Maskrays of the genus Neotrygon (Dasyatidae) have dispersed widely in the Indo-West Pacific being represented largely by an assemblage of narrow-ranging coastal endemics. Phylogenetic reconstruction methods reproduced nearly identical and statistically robust topologies supporting the monophyly of the genus Neotrygon within the family Dasyatidae, the genus Taeniura being consistently basal to Neotrygon, and Dasyatis being polyphyletic to the genera Taeniurops and Pteroplatytrygon. The Neotrygon kuhlii complex, once considered to be an assemblage of color variants of the same biological species, is the most derived and widely dispersed subgroup of the genus. Mitochondrial (COI, 16S) and nuclear (RAG1) phylogenies used in synergy with molecular dating identified paleoclimatic fluctuations responsible for periods of vicariance and dispersal promoting population fragmentation and speciation in Neotrygon. Signatures of population differentiation exist in N. ningalooensis and N. annotata, yet a large-scale geological event, such as the collision between the Australian and Eurasian Plates, coupled with subsequent sea-level falls, appears to have separated a once homogeneous population of the ancestral form of N. kuhlii into southern Indian Ocean and northern Pacific taxa some 4–16 million years ago. Repeated climatic oscillations, and the subsequent establishment of land and shallow sea connections within and between Australia and parts of the Indo-Malay Archipelago, have both promoted speciation and established zones of secondary contact within the Indian and Pacific Ocean basins.
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Affiliation(s)
- Melody Puckridge
- Institute for Marine and Antarctic Studies, University of Tasmania Private Bag 129, Hobart, TAS, 7001, Australia ; Wealth from Oceans Flagship, CSIRO Marine and Atmospheric Research Castray Esplanade, Hobart, TAS, 7000, Australia
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Faria VV, McDavitt MT, Charvet P, Wiley TR, Simpfendorfer CA, Naylor GJP. Species delineation and global population structure of Critically Endangered sawfishes (Pristidae). Zool J Linn Soc 2012. [DOI: 10.1111/j.1096-3642.2012.00872.x] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
| | - Matthew T. McDavitt
- National Legal Research Group Inc.; 2421 Ivy Road; Charlottesville; VA; 22903-4971; USA
| | - Patricia Charvet
- SENAI/PR; Av. Cândido de Abreu 200; Curitiba; PR; 80530-902; Brazil
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Boomer JJ, Harcourt RG, Francis MP, Stow AJ. Genetic divergence, speciation and biogeography of Mustelus (sharks) in the central Indo-Pacific and Australasia. Mol Phylogenet Evol 2012; 64:697-703. [DOI: 10.1016/j.ympev.2012.05.024] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2012] [Revised: 05/15/2012] [Accepted: 05/21/2012] [Indexed: 10/28/2022]
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Naylor GJP, Caira JN, Jensen K, Rosana KAM, White WT, Last PR. A DNA Sequence–Based Approach To the Identification of Shark and Ray Species and Its Implications for Global Elasmobranch Diversity and Parasitology. BULLETIN OF THE AMERICAN MUSEUM OF NATURAL HISTORY 2012. [DOI: 10.1206/754.1] [Citation(s) in RCA: 282] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Portnoy DS, Heist EJ. Molecular markers: progress and prospects for understanding reproductive ecology in elasmobranchs. JOURNAL OF FISH BIOLOGY 2012; 80:1120-40. [PMID: 22497375 DOI: 10.1111/j.1095-8649.2011.03206.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Application of modern molecular tools is expanding the understanding of elasmobranch reproductive ecology. High-resolution molecular markers provide information at scales ranging from the identification of reproductively isolated populations in sympatry (i.e. cryptic species) to the relationships among parents, offspring and siblings. This avenue of study has not only augmented the current understanding of the reproductive biology of elasmobranchs but has also provided novel insights that could not be obtained through experimental or observational techniques. Sharing of genetic polymorphisms across ocean basins indicates that for some species there may be gene flow on global scales. The presence, however, of morphologically similar but genetically distinct entities in sympatry suggests that reproductive isolation can occur with minimal morphological differentiation. This review discusses the recent findings in elasmobranch reproductive biology like philopatry, hybridization and polyandry while highlighting important molecular and analytical techniques. Furthermore, the review examines gaps in current knowledge and discusses how new technologies may be applied to further the understanding of elasmobranch reproductive ecology.
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Affiliation(s)
- D S Portnoy
- Department of Wildlife and Fisheries Sciences, Center for Biosystematics and Biodiversity, Texas A&M University, College Station, TX 77843-2258, USA.
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Dudgeon CL, Blower DC, Broderick D, Giles JL, Holmes BJ, Kashiwagi T, Krück NC, Morgan JAT, Tillett BJ, Ovenden JR. A review of the application of molecular genetics for fisheries management and conservation of sharks and rays. JOURNAL OF FISH BIOLOGY 2012; 80:1789-1843. [PMID: 22497408 DOI: 10.1111/j.1095-8649.2012.03265.x] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Since the first investigation 25 years ago, the application of genetic tools to address ecological and evolutionary questions in elasmobranch studies has greatly expanded. Major developments in genetic theory as well as in the availability, cost effectiveness and resolution of genetic markers were instrumental for particularly rapid progress over the last 10 years. Genetic studies of elasmobranchs are of direct importance and have application to fisheries management and conservation issues such as the definition of management units and identification of species from fins. In the future, increased application of the most recent and emerging technologies will enable accelerated genetic data production and the development of new markers at reduced costs, paving the way for a paradigm shift from gene to genome-scale research, and more focus on adaptive rather than just neutral variation. Current literature is reviewed in six fields of elasmobranch molecular genetics relevant to fisheries and conservation management (species identification, phylogeography, philopatry, genetic effective population size, molecular evolutionary rate and emerging methods). Where possible, examples from the Indo-Pacific region, which has been underrepresented in previous reviews, are emphasized within a global perspective.
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Affiliation(s)
- C L Dudgeon
- The University of Queensland, St Lucia, Brisbane, Queensland 4072, Australia.
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Nance HA, Klimley P, Galván-Magaña F, Martínez-Ortíz J, Marko PB. Demographic processes underlying subtle patterns of population structure in the scalloped hammerhead shark, Sphyrna lewini. PLoS One 2011; 6:e21459. [PMID: 21789171 PMCID: PMC3137562 DOI: 10.1371/journal.pone.0021459] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2011] [Accepted: 06/02/2011] [Indexed: 12/14/2022] Open
Abstract
Genetic diversity (θ), effective population size (N(e)), and contemporary levels of gene flow are important parameters to estimate for species of conservation concern, such as the globally endangered scalloped hammerhead shark, Sphyrna lewini. Therefore, we have reconstructed the demographic history of S. lewini across its Eastern Pacific (EP) range by applying classical and coalescent population genetic methods to a combination of 15 microsatellite loci and mtDNA control region sequences. In addition to significant population genetic structure and isolation-by-distance among seven coastal sites between central Mexico and Ecuador, the analyses revealed that all populations have experienced a bottleneck and that all current values of θ are at least an order of magnitude smaller than ancestral θ, indicating large decreases in N(e) (θ = 4N(e)μ), where μ is the mutation rate. Application of the isolation-with-migration (IM) model showed modest but significant genetic connectivity between most sampled sites (point estimates of Nm = 0.1-16.7), with divergence times (t) among all populations significantly greater than zero. Using a conservative (i.e., slow) fossil-based taxon-specific phylogenetic calibration for mtDNA mutation rates, posterior probability distributions (PPDs) for the onset of the decline in N(e) predate modern fishing in this region. The cause of decline over the last several thousand years is unknown but is highly atypical as a post-glacial demographic history. Regardless of the cause, our data and analyses suggest that S. lewini was far more abundant throughout the EP in the past than at present.
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Affiliation(s)
- Holly A. Nance
- Department of Biological Sciences, Clemson University, Clemson, South Carolina, United States of America
| | - Peter Klimley
- Department of Wildlife, Fish, and Conservation Biology, University of California Davis, Davis, California, United States of America
| | | | | | - Peter B. Marko
- Department of Biological Sciences, Clemson University, Clemson, South Carolina, United States of America
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Abstract
This article reviews recent developments in Bayesian algorithms that explicitly include geographical information in the inference of population structure. Current models substantially differ in their prior distributions and background assumptions, falling into two broad categories: models with or without admixture. To aid users of this new generation of spatially explicit programs, we clarify the assumptions underlying the models, and we test these models in situations where their assumptions are not met. We show that models without admixture are not robust to the inclusion of admixed individuals in the sample, thus providing an incorrect assessment of population genetic structure in many cases. In contrast, admixture models are robust to an absence of admixture in the sample. We also give statistical and conceptual reasons why data should be explored using spatially explicit models that include admixture.
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Affiliation(s)
- Olivier François
- Grenoble IT, Joseph Fourier University, CNRS UMR 5525, TIMC, Group of Computational and Mathematical Biology, 38706 La Tronche, France
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Veríssimo A, McDowell JR, Graves JE. Global population structure of the spiny dogfish Squalus acanthias, a temperate shark with an antitropical distribution. Mol Ecol 2010; 19:1651-62. [PMID: 20345677 DOI: 10.1111/j.1365-294x.2010.04598.x] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The spiny dogfish (Squalus acanthias) is a temperate, coastal squaloid shark with an antitropical distribution in the Atlantic and Pacific oceans. The global population structure of this species is poorly understood, although individuals are known to undergo extensive migrations within coastal waters and across ocean basins. In this study, an analysis of the global population structure of the spiny dogfish was conducted using eight polymorphic nuclear microsatellite markers and a 566-bp fragment of the mitochondrial ND2 gene region. A low level of genetic divergence was found among collections from the Atlantic and South Pacific basins, whereas a high level of genetic divergence was found among Pacific Ocean collections. Two genetically distinct groups were recovered by both marker classes: one exclusive to North Pacific collections, and one including collections from the South Pacific and Atlantic locations. The strong genetic break across the equatorial Pacific coincides with major regional differences in the life-history characters of spiny dogfish, suggesting that spiny dogfish in areas on either side of the Pacific equator have been evolving independently for a considerable time. Phylogeographic analyses indicate that spiny dogfish populations had a Pacific origin, and that the North Atlantic was colonized as a result of a recent range expansion from the South American coast. Finally, the available data strongly argue for the taxonomic separation of the North Pacific spiny dogfish from S. acanthias and a re-evaluation of the specific status of S. acanthias is warranted.
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Affiliation(s)
- A Veríssimo
- Virginia Institute of Marine Science, College of William & Mary, P.O. Box 1346, Gloucester Point, VA 23062, USA.
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Schluessel V, Broderick D, Collin SP, Ovenden JR. Evidence for extensive population structure in the white-spotted eagle ray within the Indo-Pacific inferred from mitochondrial gene sequences. J Zool (1987) 2010. [DOI: 10.1111/j.1469-7998.2009.00680.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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AHONEN H, HARCOURT RG, STOW AJ. Nuclear and mitochondrial DNA reveals isolation of imperilled grey nurse shark populations (Carcharias taurus). Mol Ecol 2009; 18:4409-21. [DOI: 10.1111/j.1365-294x.2009.04377.x] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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Ovenden JR, Kashiwagi T, Broderick D, Giles J, Salini J. The extent of population genetic subdivision differs among four co-distributed shark species in the Indo-Australian archipelago. BMC Evol Biol 2009; 9:40. [PMID: 19216767 PMCID: PMC2660307 DOI: 10.1186/1471-2148-9-40] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2008] [Accepted: 02/12/2009] [Indexed: 12/01/2022] Open
Abstract
Background The territorial fishing zones of Australia and Indonesia are contiguous to the north of Australia in the Timor and Arafura Seas and in the Indian Ocean to the north of Christmas Island. The area surrounding the shared boundary consists of a variety of bio-diverse marine habitats including shallow continental shelf waters, oceanic trenches and numerous offshore islands. Both countries exploit a variety of fisheries species, including whaler (Carcharhinus spp.) and hammerhead sharks (Sphyrna spp.). Despite their differences in social and financial arrangements, the two countries are motivated to develop complementary co-management practices to achieve resource sustainability. An essential starting point is knowledge of the degree of population subdivision, and hence fisheries stock status, in exploited species. Results Populations of four commercially harvested shark species (Carcharhinus obscurus, Carcharhinus sorrah, Prionace glauca, Sphyrna lewini) were sampled from northern Australia and central Indonesia. Neutral genetic markers (mitochondrial DNA control region sequence and allelic variation at co-dominant microsatellite loci) revealed genetic subdivision between Australian and Indonesian populations of C. sorrah. Further research is needed to address the possibility of genetic subdivision among C. obscurus populations. There was no evidence of genetic subdivision for P. glauca and S. lewini populations, but the sampling represented a relatively small part of their distributional range. For these species, more detailed analyses of population genetic structure is recommended in the future. Conclusion Cooperative management between Australia and Indonesia is the best option at present for P. glauca and S. lewini, while C. sorrah and C. obscurus should be managed independently. On-going research on these and other exploited shark and ray species is strongly recommended. Biological and ecological similarity between species may not be a predictor of population genetic structure, so species-specific studies are recommended to provide new data to assist with sustainable fisheries management.
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Affiliation(s)
- Jenny R Ovenden
- Molecular Fisheries Laboratory, Department of Primary Industries and Fisheries, Queensland Government, Queensland, Australia.
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