Isolation by environment in the highly mobile olive ridley turtle (Lepidochelys olivacea) in the eastern Pacific
File(s)
Accepted version
Author(s)
Rodríguez-Zárate, Clara J
Sandoval-Castillo, Jonathan
van Sebille, Erik
Keane, Robert G
Rocha-Olivares, Axayácatl
Type
Journal Article
Abstract
Spatial and temporal scales at which processes modulate genetic diversity over the landscape are usually overlooked, impacting the design of conservation management practices for widely distributed species. We examine processes shaping population divergence in highly mobile species by re-assessing the case of panmixia in the iconic olive ridley turtle from the eastern Pacific. We implemented a biophysical model of connectivity and a seascape genetic analysis based on nuclear DNA variation of 634 samples collected from 27 nesting areas. Two genetically distinct populations largely isolated during reproductive migrations and mating were detected, each composed of multiple nesting sites linked by high connectivity. This pattern was strongly associated with a steep environmental gradient and also influenced by ocean currents. These findings relate to meso-scale features of a dynamic oceanographic interface in the eastern tropical Pacific (ETP) region, a scenario that possibly provides different cost-benefit solutions and selective pressures for sea turtles during both the mating and migration periods. We reject panmixia and propose a new paradigm for olive ridley turtles where reproductive isolation due to assortative mating is linked to its environment. Our study demonstrates the relevance of integrative approaches for assessing the role of environmental gradients and oceanographic currents as drivers of genetic differentiation in widely distributed marine species. This is relevant for the conservation management of species of highly mobile behaviour, and assists the planning and development of large-scale conservation strategies for the threatened olive ridley turtles in the ETP.
Date Issued
2018-05-16
Date Acceptance
2018-04-10
Citation
Proceedings of the Royal Society B: Biological Sciences, 2018, 285 (1878)
ISSN
1471-2954
Publisher
Royal Society, The
Journal / Book Title
Proceedings of the Royal Society B: Biological Sciences
Volume
285
Issue
1878
Copyright Statement
© 2018 The Author(s) Published by the Royal Society. All rights reserved.
Identifier
https://www.ncbi.nlm.nih.gov/pubmed/29720414
PII: rspb.2018.0264
Subjects
conservation genetics
landscape genetics
marine connectivity
panmixia
sea turtles
seascape genetics
Publication Status
Published
Coverage Spatial
England
Date Publish Online
2018-05-02