Evidence of historical isolation and genetic structuring among broadnose sevengill sharks (Notorynchus cepedianus) from the world’s major oceanic regions

Authors

Alicia C. J. Schmidt-Roach, Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia
Christine C. Bruels, Department of Biological Sciences, Nova Southeastern University, Save Our Seas Foundation Shark Research Center and, Guy Harvey Research Institute, Dania Beach, Florida, USA
Adam Barnett, James Cook University, Cairns, Queensland, Australia
Adam D. Miller, Deakin University, Geelong, Victora, Australia
Craig D. H. Sherman, Deakin University, Geelong, Victora, Australia
David A. Ebert, Pacific Shark Research Center, Moss Landing Marine Laboratories, Moss Landing, California, USA
Sebastian Schmidt-Roach, Red Sea Research Center, King Abdullah University for Science and Technology (KAUST), Thuwal, Saudi Arabia
Charlene da Silva, Department of Environment, Forestry and Fisheries, Fisheries Research and Development, Pretoria, South Africa
Christopher G. Wilke, Department of Environment, Forestry and Fisheries, Fisheries Research and Development, Pretoria, South Africa
Craig Thorburn, Kelly Tarltons Sea Life Aquarium, Auckland, New Zealand
Jeffrey C. Mangel, ProDelphinus, Lima, Peru
Juan Manuel Ezcurra, Monterey Bay Aquarium, Monterey, CA, USA
Alejo Irigoyen, Centro Para el Estudio de Sistemas Marinos (CESIMAR), Consejo Nacional de Investigaciones Científicas y Técnicas (CCT CENPAT – CONICET), Puerto Madryn, Chubut, Argentina
Andrés Javier Jaureguizar, Comisión de Investigaciones Científicas de La Provincia de Buenos Aires (CIC), La Plata, Buenos Aires, República Argentina
Matias Braccini, Department of Primary Industries and Regional Development, Western AustraliaFollow
Joanna Alfaro-Shigueto, ProDelphinus, Lima, Peru
Clinton Duffy, Department of Conservation, Auckland, New Zealand
Mahmood S. Shivji, Department of Biological Sciences, Nova Southeastern University, Save Our Seas Foundation Shark Research Center and, Guy Harvey Research Institute, Dania Beach, Florida, USA

Document Type

Article

Publication Date

3-26-2021

Journal Title

Reviews in Fish Biology and Fisheries

ISSN

Print: 0960-3166 Electronic: 1573-5184

Keywords

Global distribution, Phylogeography, Pleistocene, Population structure patterns, Sharks, Species management

Disciplines

Aquaculture and Fisheries | Data Science | Genetics | Genomics | Marine Biology | Natural Resources and Conservation | Natural Resources Management and Policy | Oceanography | Sustainability

Abstract

Cosmopolitan marine pelagic species display variable patterns of population connectivity among the world’s major oceans. While this information is crucial for informing management, information is lacking for many ecologically important species, including apex predators. In this study we examine patterns of genetic structure in the broadnose sevengill shark, Notorynchus cepedianus across its global distribution. We estimate patterns of connectivity among broadnose sevengill shark populations from three major oceanic regions (South Atlantic, Oceania and Eastern Pacific) by contrasting mitochondrial and nuclear DNA haplotype frequencies. We also produced time calibrated Bayesian Inference phylogenetic reconstructions to analyses global phylogeographic patterns and estimate divergence times among distinctive shark lineages. Our results demonstrate significant genetic differentiation among oceanic regions (ΦST = 0.9789, P < 0.0001) and a lack of genetic structuring within regions (ΦST = − 0.007; P = 0.479). Time calibrated Bayesian Inference phylogenetic reconstructions indicate that the observed patterns of genetic structure among oceanic regions are historical, with regional populations estimated to have diverged from a common ancestor during the early to mid-Pleistocene. Our results indicate significant genetic structuring and a lack of gene flow among broadnose sevengill shark populations from the South Atlantic, Oceania and Eastern Pacific regions. Evidence of deep lineage divergences coinciding with the early to mid-Pleistocene suggests historical glacial cycling has contributed to the vicariant divergence of broadnose sevengill shark populations from different ocean basins. These finding will help inform global management of broadnose sevengill shark populations, and provides new insights into historical and contemporary evolutionary processes shaping populations of this ecologically important apex predator.

Recommended Citation

Schmidt-Roach, A.C.J., Bruels, C.C., Barnett, A. et al. Evidence of historical isolation and genetic structuring among broadnose sevengill sharks (Notorynchus cepedianus) from the world’s major oceanic regions. Rev Fish Biol Fisheries 31, 433–447 (2021). https://doi.org/10.1007/s11160-021-09651-1