Juvenile ecology drives adult morphology in two insect orders

Most animals undergo ecological niche shifts between distinct life phases,but such shifts can result in adaptive conflicts of phenotypic traits. Metamor-phosis can reduce these conflicts by breaking up trait correlations, allowingeach life phase to independently adapt to its ecological niche. This process iscalled adaptive decoupling. It is, however, yet unknown to what extentadaptive decoupling is realized on a macroevolutionary scale in hemimeta-bolous insects and if the degree of adaptive decoupling is correlated with thestrength of ontogenetic niche shifts. It is also unclear whether the degree ofadaptive decoupling is correlated with phenotypic disparity. Here, we quan-tify nymphal and adult trait correlations in 219 species across the wholephylogeny of earwigs and stoneflies to test whether juvenile and adulttraits are decoupled from each other. We demonstrate that adult head mor-phology is largely driven by nymphal ecology, and that adult head shapedisparity has increased with stronger ontogenetic niche shifts in some stone-fly lineages. Our findings implicate that the hemimetabolan metamorphosisin earwigs and stoneflies does not allow for high degrees of adaptive decou-pling, and that high phenotypic disparity can even be realized when theevolution of distinct life phases is coupled

An Update on the Content of Fatty Acids, Dioxins, PCBs and Heavy Metals in Farmed, Escaped and Wild Atlantic Salmon (Salmo salar L.) in Norway

In this paper, we present updated data on proximate composition, amino acid, and fatty acid composition, as well as concentrations of dioxins, polychlorinated biphenyls (PCBs), and selected heavy metals, in fillets from farmed (n = 20), escaped (n = 17), and wild (n = 23) Atlantic salmon (Salmo salar L.). The concentrations of dioxins (0.53 ± 0.12 pg toxic equivalents (TEQ)/g), dioxin-like PCBs (0.95 ± 0.48 pg TEQ/g), mercury (56.3 ± 12.9 µg/kg) and arsenic (2.56 ± 0.87 mg/kg) were three times higher in wild compared to farmed salmon, but all well below EU-uniform maximum levels for contaminants in food. The six ICES (International Council for the Exploration of the Sea) PCBs concentrations (5.09 ± 0.83 ng/g) in wild salmon were higher than in the farmed fish (3.34 ± 0.46 ng/g). The protein content was slightly higher in wild salmon (16%) compared to the farmed fish (15%), and the amount of essential amino acids were similar. The fat content of farmed salmon (18%) was three times that of the wild fish, and the proportion of marine long-chain omega-3 fatty acids was a substantially lower (8.9 vs. 24.1%). The omega-6 to omega-3 fatty acid ratio was higher in farmed than wild salmon (0.7 vs. 0.05). Both farmed and wild Atlantic salmon are still valuable sources of eicosapentaenoic acid and docosahexaenoic acid. One 150 g portion per week will contribute to more (2.1 g and 1.8 g) than the recommended weekly intake for adults

Juvenile ecology drives adult morphology in two insect orders

Most animals undergo ecological niche shifts between distinct life phases, but such shifts can result in adaptive conflicts of phenotypic traits. Metamorphosis can reduce these conflicts by breaking up trait correlations, allowing each life phase to independently adapt to its ecological niche. This process is called adaptive decoupling. It is, however, yet unknown to what extent adaptive decoupling is realized on a macroevolutionary scale in hemimetabolous insects and if the degree of adaptive decoupling is correlated with the strength of ontogenetic niche shifts. It is also unclear whether the degree of adaptive decoupling is correlated with phenotypic disparity. Here, we quantify nymphal and adult trait correlations in 219 species across the whole phylogeny of earwigs and stoneflies to test whether juvenile and adult traits are decoupled from each other. We demonstrate that adult head morphology is largely driven by nymphal ecology, and that adult head shape disparity has increased with stronger ontogenetic niche shifts in some stonefly lineages. Our findings implicate that the hemimetabolan metamorphosis in earwigs and stoneflies does not allow for high degrees of adaptive decoupling, and that high phenotypic disparity can even be realized when the evolution of distinct life phases is coupled