Preference versus performance: Investigating the dissociation between objective measures and subjective ratings of usability for schematic metro maps and intuitive theories of design

Three experiments are reported in which objective measures and subjective ratings of schematic metro map usability were investigated. Experiment 1 used a within-subjects design to compare octolinear and curvilinear Paris Metro maps. This replicated and extended Roberts et al. (2013); the curvilinear map was associated with faster journey planning times, and yet preference between the two was unrelated to this measure. In Experiment 2, nine matched versions of the London Underground map were rated for usability and attractiveness, and a clear octolinear bias was displayed. It was also possible to identify individuals who held a simplicity theory of effective design, versus an octolinearity theory. Experiment 3 investigated the relationship between usability ratings and journey planning times for three Berlin network maps, all optimized for simplicity of line trajectories. No differences in times were found, and yet usability ratings after experience at using the maps differed significantly, in line with the findings for the London designs in Experiment 2. Overall, the dissociation between objective measures of performance and subjective ratings of usability is robust, and appears to reflect expectations and prejudices concerning effective design. The octolinearity as a gold standard conjecture for achieving optimum usability continues to be refuted

Evolution of diadromy in fish: insights from a tropical genus (Kuhlia species)

Diadromous species undergo regular migration between fresh and marine waters. This behavior is found in many species, including fish, mollusks, and crustaceans, some of which are commercially valuable species. Several attempts to trace the evolution of this behavior have been made in Salmonidae and Galaxiidae, but ambiguous phylogenies and multiple character state changes prevented unequivocal conclusions. The Kuhliidae family consists of 12 fish species that inhabit tropical islands in the Indo-Pacific region. The species have marine, partially catadromous, or fully catadromous life histories (i.e., they migrate from rivers to the sea to reproduce). The evolution of migratory behavior was traced on a well-resolved phylogeny. Catadromous Kuhlia species were basal, and partially catadromous and marine species formed derived monophyletic groups. This is, to our knowledge, the first time that a clear origin and polarity for the diadromous character has been demonstrated. We propose that the relative lack of resources in tropical, inshore, marine habitats and the ephemeral and isolated nature of freshwater environments of tropical islands, combined with phenotypic plasticity of migratory traits, play key roles in driving the evolution of diadromy in the Kuhliidae and probably in other groups. This work is an important starting point to understand the role of diadromy in speciation and adaptation in unstable habitats

Assessment of genetic structure among Australian east coast populations of snapper Chrysophrys auratus (Sparidae)

Snapper Chrysophrys auratus is a high-value food fish in Australia targeted by both commercial and recreational fisheries. Along the east coast of Australia, fisheries are managed under four state jurisdictions (Queensland, Qld; New South Wales, NSW; Victoria, Vic.; and Tasmania, Tas.), each applying different regulations, although it is thought that the fisheries target the same biological stock. An allozyme-based study in the mid-1990s identified a weak genetic disjunction north of Sydney (NSW) questioning the single-stock hypothesis. This study, focused on east-coast C. auratus, used nine microsatellite markers to assess the validity of the allozyme break and investigated whether genetic structure exists further south. Nine locations were sampled spanning four states and over 2000 km, including sites north and south of the proposed allozyme disjunction. Analyses confirmed the presence of two distinct biological stocks along the east coast, with a region of genetic overlap around Eden in southern NSW, ~400 km south of the allozyme disjunction. The findings indicate that C. auratus off Vic. and Tas. are distinct from those in Qld and NSW. For the purpose of stock assessment and management, the results indicate that Qld and NSW fisheries are targeting a single biological stock.

Population structure and connectivity of tiger sharks (Galeocerdo cuvier) across the Indo-Pacific Ocean basin

Population genetic structure using nine polymorphic nuclear microsatellite loci was assessed for the tiger shark () at seven locations across the Indo-Pacific, and one location in the southern Atlantic. Genetic analyses revealed considerable genetic structuring ( > 0.14,

Strong population structure deduced from genetics, otolith chemistry and parasite abundances explains vulnerability to localized fishery collapse in a large Sciaenid fish, Protonibea diacanthus

As pressure on coastal marine resources is increasing globally, the need to quantitatively assess vulnerable fish stocks is crucial in order to avoid the ecological consequences of stock depletions. Species of Sciaenidae (croakers, drums) are important components of tropical and temperate fisheries and are especially vulnerable to exploitation. The black-spotted croaker, Protonibea diacanthus, is the only large sciaenid in coastal waters of northern Australia where it is targeted by commercial, recreational and indigenous fishers due to its food value and predictable aggregating behaviour. Localised declines in the abundance of this species have been observed, highlighting the urgent requirement by managers for information on fine and broad-scale population connectivity. This study examined the population structure of P. diacanthus across northwestern Australia using three complementary methods: genetic variation in microsatellite markers, otolith elemental composition and parasite assemblage composition. The genetic analyses demonstrated that there were at least five genetically distinct populations across the study region, with gene flow most likely restricted by inshore biogeographic barriers such as the Dampier Peninsula. The otolith chemistry and parasite analyses also revealed strong spatial variation among locations within broad-scale regions, suggesting fine-scale location fidelity within the lifetimes of individual fish. The complementarity of the three techniques elucidated patterns of connectivity over a range of spatial and temporal scales. We conclude that fisheries stock assessments and management are required at fine scales (100's km) to account for the restricted exchange among populations (stocks) and to prevent localised extirpations of this species. Realistic management arrangements may involve the successive closure and opening of fishing areas to reduce fishing pressure

Assessment of genetic structure among Australian east coast populations of snapper Chrysophrys auratus (Sparidae)

Snapper Chrysophrys auratus is a high-value food fish in Australia targeted by both commercial and recreational fisheries. Along the east coast of Australia, fisheries are managed under four state jurisdictions (Queensland, Qld; New South Wales, NSW; Victoria, Vic.; and Tasmania, Tas.), each applying different regulations, although it is thought that the fisheries target the same biological stock. An allozyme-based study in the mid-1990s identified a weak genetic disjunction north of Sydney (NSW) questioning the single-stock hypothesis. This study, focused on east-coast C. auratus, used nine microsatellite markers to assess the validity of the allozyme break and investigated whether genetic structure exists further south. Nine locations were sampled spanning four states and over 2000 km, including sites north and south of the proposed allozyme disjunction. Analyses confirmed the presence of two distinct biological stocks along the east coast, with a region of genetic overlap around Eden in southern NSW, ~400 km south of the allozyme disjunction. The findings indicate that C. auratus off Vic. and Tas. are distinct from those in Qld and NSW. For the purpose of stock assessment and management, the results indicate that Qld and NSW fisheries are targeting a single biological stock.

Population genetics of Southern Hemisphere tope shark (<i>Galeorhinus galeus</i>) : Intercontinental divergence and constrained gene flow at different geographical scales

The tope shark (Galeorhinus galeus Linnaeus, 1758) is a temperate, coastal hound shark found in the Atlantic and Indo-Pacific oceans. In this study, the population structure of Galeorhinus galeus was determined across the entire Southern Hemisphere, where the species is heavily targeted by commercial fisheries, as well as locally, along the South African coastline. Analysis was conducted on a total of 185 samples using 19 microsatellite markers and a 671 bp fragment of the NADH dehydrogenase subunit 2 (ND2) gene. Across the Southern Hemisphere, three geographically distinct clades were recovered, including one from South America (Argentina, Chile), one from Africa (all the South African collections) and an Australia-New Zealand clade. Nuclear data revealed significant population subdivisions (FST = 0.192 to 0.376, p<0.05) indicating limited gene flow for tope sharks across ocean basins. Marked population connectivity was however evident across the Indian Ocean based on Bayesian clustering analysis. More locally in South Africa, F-statistics and multivariate analysis supported moderate to high gene flow across the Atlantic/ Indian Ocean boundary (FST = 0.035 to 0.044, p<0.05), with exception of samples from Struisbaai and Port Elizabeth which differed significantly from the rest. Discriminant and Bayesian clustering analysis indicated admixture in all sampling populations, decreasing from west to east, corroborating possible restriction to gene flow across regional oceanographic barriers. Mitochondrial sequence data recovered seven haplotypes (h = 0.216, π = 0.001) for South Africa, with one major haplotype shared by 87% of the individuals and at least one private haplotype for each sampling location except Port Elizabeth. As with many other coastal shark species with cosmopolitan distribution, this study confirms the lack of both historical dispersal and inter-oceanic gene flow while also implicating contemporary factors such as oceanic currents and thermal fronts to drive local genetic structure of G. galeus on a smaller spatial scale.Facultad de Ciencias Naturales y Muse

Harnessing the Power of Genomics to Secure the Future of Seafood

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.Peer reviewe

Supporting data for study "Patterns of allozyme variation in narrow-barred Spanish mackerel (Scomberomorus commerson) reveal population subdivision in the Australia-Torres Strait-New Guinea region".

Over 2,300 fish from eighteen collections were characterized using 28 variable loci. Allele frequencies at the three locations sampled more than once were stable over a two- to three-year period.&nbsp;&nbsp;&nbsp; Contains supplementary tables and figures