Marine & Environmental Sciences Faculty Articles
Genetic Connectivity of a Coral Reef Ecosystem Predator: The Population Genetic Structure and Evolutionary History of the Caribbean Reef Shark (Carcharhinus perezi)
ResearcherID
G-4080-2013
Document Type
Article
Publication Title
Journal of Biogeography
ISSN
0305-0270
Publication Date
7-26-2017
Keywords
Coral reefs, Elasmobranch, Evolutionary history, Marine biogeography, Microsatellite DNA, Mitochondrial DNA, Population structure, Western Atlantic
Abstract
Aim
The Caribbean reef shark (Carcharhinus perezi) is one of few extant reef sharks inhabiting the Atlantic Ocean. Its variability in movements across habitat types suggests the possibility of a complex genetic population structure. Here, we use mitochondrial and nuclear DNA to investigate the genetic connectivity of the Caribbean reef shark across contemporary and evolutionary time-scales and relate our findings to the ecology of this understudied species.
Location
Tropical western Atlantic and Caribbean.
Methods
Samples were obtained from 216 individuals from six western Atlantic and Caribbean locations. Individuals were genotyped at seven nuclear microsatellite DNA loci and sequenced at two mitochondrial (control region [CR]; NADH dehydrogenase subunit 4 [ND4]) and one nuclear locus (lactate dehydrogenase [LDH]). Analyses to resolve the population genetic structure and evolutionary history of this species were adopted.
Results
Sequencing of the CR (1,068 bp, n = 216), ND4 (741 bp, n = 213) and LDH (258 bp, n = 165) loci, resolved 11, 8 and 13 unique haplotypes (or alleles), respectively. Overall, Caribbean reef sharks showed low levels of genetic diversity and most marker sets identified strong genetic differences (FSTand ΦST) between sharks sampled in Brazil versus all other locations (msat FST > 0.017; CR-ND4 ΦST > 0.013). Mitochondrial DNA showed evidence of increased genetic partitioning among western North Atlantic sampling sites, although widespread haplotype sharing (~85%–92%) and a shallow population history were found.
Main Conclusions
Findings of genetic differentiation are concordant with previous movement studies showing residency and/or site-fidelity to specific locations by individuals. However, similar to other reef shark studies, we found that the level of genetic connectivity among populations was context dependent—i.e., sharks occupying isolated habitats showed greater genetic differentiation compared with those sharks occupying semi-isolated or continuous reef habitats. Furthermore, low genetic diversity and a shallow mitochondrial population history were found, suggesting historical demographic fluctuations, including population collapse and more recent expansions.
DOI
10.1111/jbi.13062
First Page
1
Last Page
13
Additional Comments
Sao Paulo Research Foundation grant #: FAPESP #1998/15080-8
NSUWorks Citation
Andrea Bernard, Rebekah L. Horn, Demian D. Chapman, Kevin A. Feldheim, Ricardo C. Garla, Edd J. Brooks, Mauvis A. Gore, and Mahmood S. Shivji. 2017. Genetic Connectivity of a Coral Reef Ecosystem Predator: The Population Genetic Structure and Evolutionary History of the Caribbean Reef Shark (Carcharhinus perezi) .Journal of Biogeography : 1 -13. https://nsuworks.nova.edu/occ_facarticles/809.
Comments
©2017 John Wiley & Sons Ltd