Best use of scientific knowledge is required to maintain the fundamental role of seafood in human nutrition. While it is acknowledged that genomic-based methods allow the collection of powerful data, their value to inform fisheries management, aquaculture, and biosecurity applications remains underestimated. We review genomic applications of relevance to the sustainable management of seafood resources, illustrate the benefits of, and identify barriers to their integration. We conclude that the value of genomic information towards securing the future of seafood does not need to be further demonstrated. Instead, we need immediate efforts to remove structural roadblocks and focus on ways that support integration of genomic-informed methods into management and production practices. We propose solutions to pave the way forward.

Insight into the processes of evolutionary change can be obtained by studying the distribution of genetic diversity among populations. Such diversity can be shaped by historical colonization events, population connectivity and adaptation to local selection pressures. Here we examine genetic differentiation of Trinidadian guppies, Poecilia reticulata, by genotyping 373 individuals from 15 populations located in three drainages (northern coast, Caroni and Oropouche) with 7 microsatellite loci. Our data provide little evidence to support previous claims of two major genetic lineages of guppies in northern Trinidad but instead suggest a more complex pattern of gene flow among populations from different drainages. First, some of the populations in the Caroni drainage show genetic signatures similar to those in the Oropouche drainage. Second, the populations in the northern coast are all highly differentiated from those in either the Caroni or Oropouche drainages. Despite differing selection regimes owing to predation pressure, populations from upstream and downstream locales typically cluster together, albeit upstream populations consistently have less genetic variability than the corresponding downstream population. There is, however, no overall pattern of isolation by distance. We also find evidence that an artificially transplanted population from the Caroni drainage is successfully invading into other populations within the Oropouche system. Our analysis details the genetic and phylogeographic structure of Trinidadian guppies in the northern range and provides insight into evolutionary processes at different timescales that have shaped genetic heterogeneity in this fish.

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Fluctuating asymmetry (FA), the small random deviations from perfect morphological symmetry that result during development, is ubiquitous throughout the animal kingdom. In many species, FA seems to play a role in mate choice, perhaps because it signals an individual's genetic quality and health. However, the relationship between an individual's FA and behaviour is generally unknown: what do more asymmetric individuals do about their own asymmetry? We now show for the first time that individuals respond behaviourally to their own morphological FA in what appears to be an adaptive manner. During courtship, male guppies exhibiting high FA in ornamental colour, bias their displays towards their more colourful body side, thus potentially increasing their attractiveness by exaggerating the quantity of their orange signal. This appears to be a strictly behavioural male response to cues provided by females, as it does not occur when males court a non-reactive model female. Whether inferior males realize any mating advantage remains uncertain, but our study clearly demonstrates a behavioural response to random morphological asymmetries that appears to be adaptive. We propose that the tendency to show or otherwise use a 'best side' is common in nature, with implications for sexual signalling and the evolution of more pronounced asymmetries.

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The contemporary distribution and genetic structure of a freshwater fish provide insight into its historical geodispersal and geographical isolation following Quaternary climate changes. The short ninespine stickleback, Pungitius kaibarae, is a small gasterosteid fish occurring in freshwater systems on the Korean Peninsula and in southeast Russia. On the Korean Peninsula, P. kaibarae populations are distributed in three geographically separated regions: the NE (northeast coast), SE (southeast coast), and a limited area in the ND (Nakdong River). In this study, we used mitochondrial loci and microsatellites to investigate the evolutionary history of P. kaibarae populations by assessing their pattern of genetic structure. Our analyses revealed a marked level of divergence among three regional populations, suggesting a long history of isolation following colonization, although ND individuals showed relatively higher genetic affinity to populations from SE than those from NE. The populations from NE showed a great degree of interpopulation differentiation, whereas populations from SE exhibited only weak genetic structuring. Upon robust phylogenetic analysis, P. kaibarae formed a monophyletic group with Russian P. sinensis and P. tymensis with strong node confidence values, indicating that P. kaibarae populations on the Korean Peninsula originated from the southward migration of its ancestral lineage around the middle Pleistocene.

Hemistepsin A (HsA), a natural sesquiterpene lactone isolated from Hemistepta lyrata, has been known as a wide range of anti-tumor effects. The aim of this study was to determine whether HsA suppresses hepatocellular carcinoma (HCC) and to figure out the cellular signaling pathways involved in the anti-HCC activities by experiments using the Huh7 cells (a human HCC cell line) and a xenograft HCC model. In this study, HsA completely inhibited HCC cell proliferation, presumably because it induced G0/G1 cell cycle arrest and mitochondrial-related apoptosis. HsA up-regulated p53, p21, cleaved caspase-3 and cleaved PARP (poly (ADP-ribose) polymerase), but reduced cyclin D, CDK6 and Bcl-2 expressions, and it disrupted mitochondrial membrane potential (ΔΨm). Moreover, phosphorylation of AMP-activated protein kinase (AMPK) was increased by HsA as did the resveratrol and 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR, positive controls). Inhibition of AMPK by using compound C, a competent inhibitor of AMPK, attenuated the loss of ΔΨm, p53 up-regulation and cellular senescence. The efficacy of HsA to reduce HCC cell proliferation, compared to that of other known anti-HCC agents, appears to be similar or slightly better. The anti-tumor effect of HsA was also determined in mice, showing reduced growth of xenografted tumors with no weight loss. Overall, the results suggest that HsA should be considered as a candidate anti-HCC drug.

Introduction of exotic species poses a tremendous challenge to the preservation of original biodiversity and productivity in natural ecosystems. The yellow-legged Asian hornet Vespa velutina nigrithorax, which is native to tropical/subtropical areas in Indo-China, was identified in 2003 for the first time in South Korea and has established itself in a short period of time. Population genetic study of invasive species may provide exceptional opportunities to test evolutionary theory as well as patterns of colonization from the beginning of the process. Here, the genetic variability of this invasive hornet was examined using seven microsatellites to estimate the propagule pressure and to expect the spreading pathway of this invasive hornet across its range. Overall, there was a significant loss of genetic diversity in its invaded ranges compared to its native range, suggesting that this invasive hornet was introduced via a very small number of propagules. Our results also support that this invasive hornet has experienced a severe bottleneck, as a large reduction was mainly observed in the number of alleles but not in heterozygosity. No significant genetic structuring among populations was found. This study provides baseline information about the current demographic status of the invaded populations, which will help governing agencies prevent further invasions and manage native ecosystems.