Inferring temperature adaptation from thermal performance curves of somatic growth rate: The importance of growth measurements and mortality

When comparing somatic growth thermal performance curves (TPCs), higher somatic growth across experimental temperatures is often observed for populations originating from colder environments. Such countergradient variation has been suggested to represent adaptation to seasonality, or shorter favourable seasons in colder climates. Alternatively, populations from cold climates may outgrow those from warmer climates at low temperature, and vice versa at high temperature, representing adaptation to temperature. Using modelling, we show that distinguishing between these two types of adaptation based on TPCs requires knowledge about (i) the relationship between somatic growth rate and population growth rate, which in turn depends on the scale of somatic growth (absolute or proportional), and (ii) the relationship between somatic growth rate and mortality rate in the wild. We illustrate this by quantifying somatic growth rate TPCs for three populations of Daphnia magna where population growth scales linearly with proportional somatic growth. For absolute somatic growth, the northern population outperformed the two more southern populations across temperatures, and more so at higher temperatures, consistent with adaptation to seasonality. In contrast, for the proportional somatic growth TPCs, and hence population growth rate, TPCs tended to converge towards the highest temperatures. Thus, if the northern population pays an ecological mortality cost of rapid growth in the wild, this may create crossing population growth TPCs consistent with adaptation to temperature. Future studies within this field should be more explicit in how they extrapolate from somatic growth in the lab to fitness in the wild.     

Understanding New Zealand’s consumption-based greenhouse gas emissions: an application of multi-regional input-output analysis

The International Journal of Life Cycle Assessment - Consumption- and production-based accounting approaches for national greenhouse gas (GHG) emissions provide different insights to support...     

Divergence in rates of phenotypic plasticity among ectotherms

An individual's fitness cost associated with environmental change likely depends on the rate of adaptive phenotypic plasticity, and yet our understanding of plasticity rates in an ecological and evolutionary context remains limited. We provide the first quantitative synthesis of existing plasticity rate data, focusing on acclimation of temperature tolerance in ectothermic animals, where we demonstrate applicability of a recently proposed analytical approach. The analyses reveal considerable variation in plasticity rates of this trait among species, with half-times (how long it takes for the initial deviation from the acclimated phenotype to be reduced by 50% when individuals are shifted to a new environment) ranging from 3.7 to 770.2 h. Furthermore, rates differ among higher taxa, being higher for amphibians and reptiles than for crustaceans and fishes, and with insects being intermediate. We argue that a more comprehensive understanding of phenotypic plasticity will be attained through increased focus on the rate parameter.     

Ultrastructural and biochemical nuclear aspects of Eukaryote classification: Independent evolution of the dinoflagellates as a sister group of the actual Eukaryotes?

Structural and functional features of the dinoflagellate nucleus are examined and compared to those commonly found in Prokaryotes and in Eukaryotes. It appears that dinoflagellate protists, while showing several ancestral characters also found in Prokaryotes are above the prokaryote level in terms of their organization but below that of the other Eukaryotes. Some characters are typical of dinoflagellate nuclei alone, and no correspondence is found in either bacterial nucleoïd or typical eukaryote nuclei. This supports Loeblich's (1976) proposal that dinoflagellate evolution may have been independent of that of the Eukaryotes. This concept can now be refined using an argumentation plansensu Hennig (Hennig and Schlee, 1978) and appears to be in accordance with the Mesokaryote model introduced by Dodge (1965).     

A Synthetic Approach to Reconstruct the Evolutionary and Functional Innovations of the Plant Histone Variant H2A.W

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Interbreeding between local and translocated populations of a cleaner fish in an experimental mesocosm predicts risk of disrupted local adaptation

Translocation of organisms within or outside its native range carries the risk of modifying the community of the recipient ecosystems and induces gene flow between locally adapted populations or closely related species. In this study, we evaluated the genetic consequences of large‐scale translocation of cleaner wrasses that has become a common practice within the salmon aquaculture industry in northern Europe to combat sea lice infestation. A major concern with this practice is the potential for hybridization of escaped organisms with the local, recipient wrasse population, and thus potentially introduce exogenous alleles and breaking down coadapted gene complexes in local populations. We investigated the potential threat for such genetic introgressions in a large seminatural mesocosm basin. The experimental setting represented a simulated translocation of corkwing wrasse (Symphodus melops) that occurs on a large scale in the Norwegian salmon industry. Parentage assignment analysis of mesocosm's offspring revealed 30% (195 out of 651 offspring) interbreeding between the two populations, despite their being genetically (F_ST = 0.094, p < 0.05) and phenotypically differentiated. Moreover, our results suggest that reproductive fitness of the translocated western population doubled that of the local southern population. Our results confirm that human translocations may overcome the impediments imposed by natural habitat discontinuities and urge for immediate action to manage the genetic resources of these small benthic wrasses.     

Advancements in Input‐Output Models and Indicators for Consumption‐Based Accounting

The use of global, multiregional input‐output (MRIO) analysis for consumption‐based (footprint) accounting has expanded significantly over the last decade. Most of the global studies on environmental and social impacts associated with consumption or embodied in international trade would have been impossible without the rapid development of extended MRIO databases. We present an overview of the developments in the field of MRIO analysis, in particular as applied to consumption‐based environmental and social footprints. We first provide a discussion of research published on various global MRIO databases and the differences between them, before focusing on the virtual laboratory computing infrastructure for potentially making MRIO databases more accessible for collaborative research, and also for supporting greater sectoral and regional detail. We discuss work that includes a broader range of extensions, in particular the inclusion of social indicators in consumption‐based accounting. We conclude by discussing the need for the development of detailed nested MRIO tables for investigating linkages between regions of different countries, and the applications of the rapidly growing field of global MRIO analysis for assessing a country's performance toward the United Nations Sustainable Development Goals.     

The effect of phosphate application on manganese content of plants grown on neutral and alkaline soils

Summary In four field experiments high rates of granular triple superphosphate and repeated sprays of manganese sulphate were applied to oats and sugar beet on land known to produce manganese-deficiency symptoms in these crops. It was found that spraying did not increase the manganese content of the foliage while application of superphosphate did.Possible explanations for this are discussed and it is suggested that the most likely one is chemical mobilization of soil manganese brought about by the reactions that the monocalcium phosphate in superphosphate undergoes in soil.