Genetic differentiation and signatures of local adaptation revealed by RADseq for a highly dispersive mud crab Scylla olivacea (Herbst, 1796) in the Sulu Sea
View/Download
Date
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Connectivity of marine populations is shaped by complex interactions between biological and physical processes across the seascape. The influence of environmental features on the genetic structure of populations has key implications for the dynamics and persistence of populations, and an understanding of spatial scales and patterns of connectivity is crucial for management and conservation. This study employed a seascape genomics approach combining larval dispersal modeling and population genomic analysis using single nucleotide polymorphisms (SNPs) obtained from RADseq to examine environmental factors influencing patterns of genetic structure and connectivity for a highly dispersive mud crab Scylla olivacea (Herbst, 1796) in the Sulu Sea. Dispersal simulations reveal widespread but asymmetric larval dispersal influenced by persistent southward and westward surface circulation features in the Sulu Sea. Despite potential for widespread dispersal across the Sulu Sea, significant genetic differentiation was detected among eight populations based on 1,655 SNPs (FST = 0.0057, p < .001) and a subset of 1,643 putatively neutral SNP markers (FST = 0.0042, p < .001). Oceanography influences genetic structure, with redundancy analysis (RDA) indicating significant contribution of asymmetric ocean currents to neutral genetic variation (R2adj = 0.133, p = .035). Genetic structure may also reflect demographic factors, with divergent populations characterized by low effective population sizes (Ne < 50). Pronounced latitudinal genetic structure was recovered for loci putatively under selection (FST = 0.2390, p < .001), significantly correlated with sea surface temperature variabilities during peak spawning months for S. olivacea (R2adj = 0.692–0.763; p < .050), suggesting putative signatures of selection and local adaptation to thermal clines. While oceanography and dispersal ability likely shape patterns of gene flow and genetic structure of S. olivacea across the Sulu Sea, the impacts of genetic drift and natural selection influenced by sea surface temperature also appear as likely drivers of population genetic structure. This study contributes to the growing body of literature documenting population genetic structure and local adaptation for highly dispersive marine species, and provides information useful for spatial management of the fishery resource.
Description
This project was funded by the Department of Science and Technology—Philippine Council for Agriculture, Aquatic, and Natural Resources Research and Development (DOST-PCAARRD project no. QSR-IA-MCR.05.01), and implemented by the University of the Philippines—Marine Science Institute (UP-MSI). MJM acknowledges support provided by the DOST-Accelerated Science and Technology Human Resource Development Program (ASTHRDP; Thesis Grant) and the UP-MSI (Thesis Writing Grant). We are deeply thankful to Dr. Evangeline Magdaong, Jeniffer De Maligaya, and Benedict Castro of the Physical Oceanography Laboratory, UP-MSI headed by Dr. Cesar Villanoy for the larval dispersal biophysical modeling, Angela Camille Aguila and Simon Alcantara for laboratory assistance, Bhenjamin Ona for the remote sensing data, Dr. Din Matias for analysis recommendations, Von Yip for QGIS assistance, and Dr. Richard Mualil and Yunadzmal Ong of Mindanao State University (MSU Tawi-Tawi) for sample collection. We also thank Sharon Magnuson and Chris Bird (Genomics Core Lab, Texas A&M University, Corpus Christi) for performing the RAD sequencing. We thank the reviewers whose comments and insights greatly improved the manuscript. This is MSI contribution number 483.
Excerpt
Keywords
Taxonomic Terms
Geographic Names
LC Subjects
Citation
Mendiola, M. J. R., & Ravago‐Gotanco, R. (2021). Genetic differentiation and signatures of local adaptation revealed by RADseq for a highly dispersive mud crab Scylla olivacea (Herbst, 1796) in the Sulu Sea. Ecology and Evolution, 11(12), 7951–7969.