Global Phylogeography with Mixed-Marker Analysis Reveals Male-Mediated Dispersal in the Endangered Scalloped Hammerhead Shark (Sphyrna lewini)

Background: The scalloped hammerhead shark, Sphyrna lewini, is a large endangered predator with a circumglobal distribution, observed in the open ocean but linked ontogenetically to coastal embayments for parturition and juvenile development. A previous survey of maternal (mtDNA) markers demonstrated strong genetic partitioning overall (global W ST = 0.749) and significant population separations across oceans and between discontinuous continental coastlines. Methodology/Principal Findings: We surveyed the same global range with increased sample coverage (N = 403) and 13 microsatellite loci to assess the male contribution to dispersal and population structure. Biparentally inherited microsatellites reveal low or absent genetic structure across ocean basins and global genetic differentiation (FST = 0.035) over an order of magnitude lower than the corresponding measures for maternal mtDNA lineages (W ST = 0.749). Nuclear allelic richness and heterozygosity are high throughout the Indo-Pacific, while genetic structure is low. In contrast, allelic diversity is low while population structure is higher for populations at the ends of the range in the West Atlantic and East Pacific. Conclusions/Significance: These data are consistent with the proposed Indo-Pacific center of origin for S. lewini, and indicate that females are philopatric or adhere to coastal habitats while males facilitate gene flow across oceanic expanses. This study includes the largest sampling effort and the most molecular loci ever used to survey the complete range of

Mercury stable isotope values for zooplankton collected during R/V Kilo Moana cruises KM1418 and KM1506 around Station ALOHA in 2014 and 2015

Dataset: Hg Isotopes ZooplanktonThis dataset contains the mercury stable isotope ratios collected in zooplankton during R/V Kilo Moana cruises around Station ALOHA (22.75N, 158W). These data were published in Motta et al., (2019) with supporting information. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/788512NSF Division of Ocean Sciences (NSF OCE) OCE-143384

Mercury stable isotope values for marine particles from R/V Kilo Moana cruises KM1418, KM1407 and KM1506 around station ALOHA in 2014 and 2015

Dataset: Hg Isotopes ParticlesThis dataset contains the mercury stable isotope ratios collected in marine particles during R/V Kilo Moana cruises around Station ALOHA. These data were published in Motta et al., (2019) with supporting information. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/788753NSF Division of Ocean Sciences (NSF OCE) OCE-143384

Mercury stable isotope values for precipitation collected around Station ALOHA from 2005 to 2014

Dataset: Hg Isotopes PrecipitationThis dataset contains the mercury stable isotope ratios collected in precipitation during R/V Kilo Moana cruises around Station ALOHA. These data were published in Motta et al., (2019) with supporting information. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/788727NSF Division of Ocean Sciences (NSF OCE) OCE-143384

Reference materials analyzed in the laboratory for THg isotopic composition

Dataset: Hg Isotopes Reference MaterialsThis dataset contains the reference materials analyzed in the laboratory for THg isotopic composition. These data were published in Motta et al., (2019) with supporting information. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/788780NSF Division of Ocean Sciences (NSF OCE) OCE-143384

Comparison of pairwise <i>F</i>_ST values between all sampling sites.

<p>Observed <i>F</i>_ST values are shown on the bottom, and <i>F′</i>_ST is on the top. <i>F′</i>_ST indicates values that have been corrected using Meirmans' standardization approach for Pairwise <i>F</i>_ST (Meirmans 2006). TEP = Tropical East Pacific, HH = Hawaii, TW = Taiwan, PH = Philippines, EA = East Australia, W = West Australia, SY = Seychelles, SA = South Africa, WAF = West Africa, SCA = South Carolina, and GM = Gulf of Mexico.</p>†<p>weakly significant (0.05≥P≥0.01).</p><p>*statistically significant (P≤0.01).</p><p>**statistically significant (P≤0.001).</p

Description of the thirteen loci used in this study averaged across all sites.

<p><i>T_a</i> = annealing temperature, <i>H_o</i> = average observed heterozygosity, <i>H_e</i> = expected average heterozygosity, <i>P</i> = significance value from comparison between <i>H_o</i> and <i>H_e</i>, <i>r</i> = frequency of null alleles, <i>A_s</i> = average number of alleles per collection site, <i>A</i> = total alleles observed at each locus.</p>1<p>Non-species-specific markers.</p>†<p>weakly significant (0.05≥P≥0.01).</p

Description of the eleven geographic sites sampled for this study, averaged across loci.

<p><i>N</i> = number of samples per site, <i>H_o</i> = average observed heterozygosity, <i>H_e</i> = expected average heterozygosity, <i>A_r</i> = allelic richness.</p

Proportions of population ancestry from each of four multi-locus lineages (C1–C4) defined by Structure [<b>52</b>].

<p>Pie charts in the top figure indicate the relative proportion of individuals from each sampling site that assign to each lineage, and the bottom figure shows individual genotypic assignments in a conventional bar plot, organized by sampling site. TEP = Tropical East Pacific, HH = Hawaii, TW = Taiwan, PH = Philippines, EA = East Australia, W = West Australia, SY = Seychelles, SA = South Africa, WAF = West Africa, SC = South Carolina, and GM = Gulf of Mexico.</p

Map showing collection sites.

<p>TEP = Tropical East Pacific, HH = Hawaii, TW = Taiwan, PH = Philippines, EA = East Australia, W = West Australia, SY = Seychelles, SA = South Africa, WAF = West Africa, SC = South Carolina, and GM = Gulf of Mexico. Sample numbers for each site are in parentheses.</p