Neural Correlates of Body Integrity Dysphoria

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Semilunar postlarval settlement periodicity ensuing from semilunar larval release cycle in the Nihonotrypaea harmandi (Crustacea,Decapoda, Axiidea,Callianassidae) population on an intertidal sandflat in an open marine coastal embayment

Many decapod crustaceans in marine intertidal habitats release larvae toward coastal oceans, from which postlarvae (decapodids: settling-stage larvae) return home. Decapodid settlement processes are poorly understood. Previous studies showed that in Kyushu, Japan, the callianassid shrimp population on an intertidal sandflat of an open bay joining the coastal ocean near a large estuary released eight batches of larvae basically in a semilunar cycle from June through October and that decapodids performed diel vertical migration, occurring in the water column nocturnally. We conducted (a) frequent sampling for population density and size-composition on the sandflat through one reproductive season, (b) planktonic and benthic sampling for decapodids around the bay mouth, and (c) current meter deployment at three points across the bay mouth for tidal harmonic analysis. On the sandflat, six batches of newly-settled decapodids (settlers) occurred in a semilunar periodicity until October, with peaks occurring 0–3 days before syzygy dates except for the first one. For larval Batches 1–4, buoyancy-driven shoreward subsurface currents during July to mid-October would transport some pre-decapodid-stage larvae (zoeae) toward the bay. The absence of expected settler Batches 7–8 would be due to the converse subsurface currents caused by water-column mixing and seasonal winds after mid-October, carrying zoeae offshore. Once in the bay, phasing of night and nighttime-averaged shoreward tidal current explained the settlement pattern for Batches 1–4. For Batches 5–6 occurring in mid-September to mid-October, water currents generated by seasonal wind and tidal forcings may have caused peak settlement after the time expected from tidally-driven decapodid transport.     

Human land uses reduce climate connectivity across North America

Climate connectivity, the ability of a landscape to promote or hinder the movement of organisms in response to a changing climate, is contingent on multiple factors including the distance organisms need to move to track suitable climate over time (i.e. climate velocity) and the resistance they experience along such routes. An additional consideration which has received less attention is that human land uses increase resistance to movement or alter movement routes and thus influence climate connectivity. Here we evaluate the influence of human land uses on climate connectivity across North America by comparing two climate connectivity scenarios, one considering climate change in isolation and the other considering climate change and human land uses. In doing so, we introduce a novel metric of climate connectivity, ‘human exposure’, that quantifies the cumulative exposure to human activities that organisms may encounter as they shift their ranges in response to climate change. We also delineate potential movement routes and evaluate whether the protected area network supports movement corridors better than non‐protected lands. We found that when incorporating human land uses, climate connectivity decreased; climate velocity increased on average by 0.3 km/year and cumulative climatic resistance increased for ~83% of the continent. Moreover, ~96% of movement routes in North America must contend with human land uses to some degree. In the scenario that evaluated climate change in isolation, we found that protected areas do not support climate corridors at a higher rate than non‐protected lands across North America. However, variability is evident, as many ecoregions contain protected areas that exhibit both more and less representation of climate corridors compared to non‐protected lands. Overall, our study indicates that previous evaluations of climate connectivity underestimate climate change exposure because they do not account for human impacts.     

Host‐plant range expansion to Gymnocladus dioica by an introduced seed predatory beetle Megabruchidius dorsalis

A seed predatory beetle, Megabruchidius dorsalis (Coleoptera: Chrysomelidae: Bruchinae) native to the Oriental region was first found to utilize a North American Gymnocladus dioica (Fabaceae: Caesalpinioideae) in its introduced area in Central Europe. A maximum of three adult exit holes were found on a single seed. Host‐plants of the bruchine beetle have been reviewed from its native and introduced regions, including a host record of Gleditsia fera from Taiwan. Our review indicated the beetle's strict oligophagy on caesalpinioid Gleditsia species. On the contrary, our finding suggests that the beetle's host‐range extends to the caesalpinioid Umtiza clade. On the plant side, this study provides a counterexample to the enemy release hypothesis that predicts fewer predators/parasites in an organism's range of introduction than in their native range; Gy. dioica is attacked by the seed predator in its introduced region, whereas in its native range it is free from seed predators.     

Spatial connectedness imposes local‐ and metapopulation‐level selection on life history through feedbacks on demography

Dispersal evolution impacts the fluxes of individuals and hence, connectivity in metapopulations. Connectivity is therefore decoupled from the structural connectedness of the patches within the spatial network. Because of demographic feedbacks, local selection also drives the evolution of other life history traits. We investigated how different levels of connectedness affect trait evolution in experimental metapopulations of the two‐spotted spider mite. We separated local‐ and metapopulation‐level selection and linked trait divergence to population dynamics. With lower connectedness, an increased starvation resistance and delayed dispersal evolved. Reproductive performance evolved locally by transgenerational plasticity or epigenetic processes. Costs of dispersal, but also changes in local densities and temporal fluctuations herein are found to be putative drivers. In addition to dispersal, demographic traits are able to evolve in response to metapopulation connectedness at both the local and metapopulation level by genetic and/or non‐genetic inheritance. These trait changes impact the persistence of spatially structured populations.     

Spatial graphs highlight how multi-generational dispersal shapes landscape genetic patterns

Current approaches that compare spatial genetic structure of a given species and the dispersal of its mobile phase can detect a mismatch between both patterns mainly due to processes acting at different temporal scales. Genetic structure result from gene flow and other evolutionary and demographic processes over many generations, while dispersal predicted from the mobile phase often represents solely one generation on a single time-step. In this study, we present a spatial graph approach to landscape genetics that extends connectivity networks with a stepping-stone model to represent dispersal between suitable habitat patches over multiple generations. We illustrate the approach with the case of the striped red mullet Mullus surmuletus in the Mediterranean Sea. The genetic connectivity of M. surmuletus was not correlate with the estimated dispersal probability over one generation, but with the stepping-stone estimate of larval dispersal, revealing the temporal scale of connectivity across the Mediterranean Sea. Our results highlight the importance of considering multiple generations and different time scales when relating demographic and genetic connectivity. The spatial graph of genetic distances further untangles intra-population genetic structure revealing the Siculo-Tunisian Strait as an important corridor rather than a barrier for gene flow between the Western- and Eastern Mediterranean basins, and identifying Mediterranean islands as important stepping-stones for gene flow between continental populations. Our approach can be easily extended to other systems and environments.