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Genomic data are being produced and archived at a prodigious rate, and current studies could become historical baselines for future global genetic diversity analyses and monitoring programs. However, when we evaluated the potential utility of genomic data from wild and domesticated eukaryote species in the world's largest genomic data repository, we found that most archived genomic datasets (86%) lacked the spatiotemporal metadata necessary for genetic biodiversity surveillance. Labor-intensive scouring of a subset of published papers yielded geospatial coordinates and collection years for only 33% (39% if place names were considered) of these genomic datasets. Streamlined data input processes, updated metadata deposition policies, and enhanced scientific community awareness are urgently needed to preserve these irreplaceable records of today's genetic biodiversity and to plug the growing metadata gap.

Coral reefs are among the most sensitive ecosystems affected by ocean warming and acidification, and are predicted to collapse over the next few decades. Reefs are predicted to shift from net accreting calcifier-dominated systems with exceptionally high biodiversity to net eroding algal-dominated systems with dramatically reduced biodiversity. Here, we present a two-year experimental study examining the responses of entire mesocosm coral reef communities to warming (+2 ℃), acidification (-0.2 pH units), and combined future ocean (+2 ℃, -0.2 pH) treatments. Contrary to modeled projections, we show that under future ocean conditions, these communities shift structure and composition yet persist as novel calcifying ecosystems with high biodiversity. Our results suggest that if climate change is limited to Paris Climate Agreement targets, coral reefs could persist in an altered state rather than collapse. [ABSTRACT FROM AUTHOR]

Reef-building coral populations are at serious risk of collapse due to the combined effects of ocean warming and acidification. Nonetheless, many corals show potential to adapt to the changing ocean conditions. Here we examine the broad sense heritability (H2) of coral calcification rates across an ecologically and phylogenetically diverse sampling of eight of the primary reef-building corals across the Indo-Pacific. We show that all eight species exhibit relatively high heritability of calcification rates under combined warming and acidification (0.23–0.56). Furthermore, tolerance to each factor is positively correlated and the two factors do not interact in most of the species, contrary to the idea of trade-offs between temperature and pH sensitivity, and all eight species can co-evolve tolerance to elevated temperature and reduced pH. Using these values together with historical data, we estimate potential increases in thermal tolerance of 1.0–1.7°C over the next 50 years, depending on species. None of these species are probably capable of keeping up with a high global change scenario and climate change mitigation is essential if reefs are to persist. Such estimates are critical for our understanding of how corals may respond to global change, accurately parametrizing modelled responses, and predicting rapid evolution. [ABSTRACT FROM AUTHOR]

Life-history traits, especially the mode and duration of larval development, are expected to strongly influence the population connectivity and phylogeography of marine species. Comparative analysis of sympatric, closely related species with differing life histories provides the opportunity to specifically investigate these mechanisms of evolution but have been equivocal in this regard. Here, we sample two sympatric sea stars across the same geographic range in temperate waters of Australia. Using a combination of mitochondrial DNA sequences, nuclear DNA sequences, and microsatellite genotypes, we show that the benthic-developing sea star, Parvulastra exigua, has lower levels of within- and among-population genetic diversity, more inferred genetic clusters, and higher levels of hierarchical and pairwise population structure than Meridiastra calcar, a species with planktonic development. While both species have populations that have diverged since the middle of the second glacial period of the Pleistocene, most P. exigua populations have origins after the last glacial maxima (LGM), whereas most M. calcar populations diverged long before the LGM. Our results indicate that phylogenetic patterns of these two species are consistent with predicted dispersal abilities; the benthic-developing P. exigua shows a pattern of extirpation during the LGM with subsequent recolonization, whereas the planktonic-developing M. calcar shows a pattern of persistence and isolation during the LGM with subsequent post-Pleistocene introgression.

We document an extreme example of reproductive trait evolution that affects population genetic structure in sister species of Parvulastra cushion stars from Australia. Self-fertilization by hermaphroditic adults and brood protection of benthic larvae causes strong inbreeding and range-wide genetic poverty. Most samples were fixed for a single allele at nearly all nuclear loci; heterozygotes were extremely rare (0.18%); mitochondrial DNA sequences were more variable, but few populations shared haplotypes in common. Isolation-with-migration models suggest that these patterns are caused by population bottlenecks (relative to ancestral population size) and low gene flow. Loss of genetic diversity and low potential for dispersal between high-intertidal habitats may have dire consequences for extinction risk and potential for future adaptive evolution in response to climate and other selective agents.

If there is any generalization to be made about populations of commercially harvested marine species, it is that they all show dramatic numerical fluctuations in both space and time. Traditional approaches to fisheries management, based on standard stock-recruitment models, have repeatedly led to overexploitation of commercially valuable stocks throughout management history. Notable examples in California fisheries include the halibut, sardine, anchovy, salmon, and urchin fisheries. A recent survey of Dungeness crab fisheries practices and catch history suggests that this fishery is also in imminent danger of collapse (Orensanz et al. 1998). It is becoming clear that sustainable management of commercially harvested finfish and shellfish with complex life cycles must include an understanding of how patterns of larval distribution, abundance and dispersal regulate adult population dynamics. This, in turn, depends on explicit knowledge of population structure as well as patterns and amount of larval dispersal between localities. However, to date inferences of the patterns and magnitude of gene flow among populations of marine invertebrates have been “deduced only through weak inference” (Hairston 1989).

I isolated and developed primers for 17 microsatellite loci in the anomuran crab Petrolisthes cinctipes as a prelude to a comprehensive analysis of genetic structure in this species. I excluded from subsequent analyses any loci that 1) produced unscorable multiband amplification products; 2) showed evidence of null alleles; 3) failed Slatkin's (1994, 1996) exact test for a fit to the Ewens sampling distribution for selectively neutral alleles; 4) did not amplify a product of the expected size; 5) failed to amplify any product from DNA extracted from the original crab from which the library was developed; or 6) exhibited non-Mendelian patterns of inheritance. Non-Mendelian inheritance was assessed by comparing the genotypes of brooded embryos to their mothers. Amplification of two loci (Pcl60b, and Pc36L) from brooded embryos revealed heterozygous amplification products that did not match either apparent allele amplified from the mother. On the basis of these criteria, 15 of the 17 loci isolated in this study are excluded. The data generated from testing for non-Mendelian inheritance also allows an inference about the mating structure of this crab. Using the two remaining loci, I found that eight often broods analyzed show evidence of multiple paternity. This result suggests that multiple paternity of broods is widespread in Petrolisthes cinctipes.