An alien approach to invasive species: objectivity and society in invasion biology

Several authors have recently argued that invasion biologists should adopt a more objective and dispassionate stance towards invasive species. Brown and Sax (Austral Ecol 29:530–536, 2004; Austral Ecol 30:481–483, 2005) assert that invasion biologists risk their objectivity, “commit the naturalist fallacy” or “embark on a slippery slope” with engaged concern about invasive species. Elsewhere, Colautti and MacIsaac (Divers Distrib 10:135–141, 2004) propose a neutral language for invasion biology, one that insulates scientific from popular discussion about invasive species. While there is certainly hyperbole about the effects of some invasive species, the type of objectivity promoted in these papers may often be inappropriate for invasion biology. It implies a policy of non-action that is inconsistent with the conservation values of many invasion biologists. To engage these values, invasion biologists can adopt deliberative methods for environmental problem-solving that involve stakeholders in their research design and which still promote high standards of scientific rigor.     

The impact of pharmacological and non‐pharmacological interventions to improve physical health outcomes in people with schizophrenia: a meta‐review of meta‐analyses of randomized controlled trials

We summarized and compared meta‐analyses of pharmacological and non‐pharmacological interventions targeting physical health outcomes among people with schizophrenia spectrum disorders. Major databases were searched until June 1, 2018. Of 3,709 search engine hits, 27 meta‐analyses were included, representing 128 meta‐analyzed trials and 47,231 study participants. While meta‐analyses were generally of adequate or high quality, meta‐analyzed studies were less so. The most effective weight reduction interventions were individual lifestyle counseling (standardized mean difference, SMD=–0.98) and exercise interventions (SMD=–0.96), followed by psychoeducation (SMD=–0.77), aripiprazole augmentation (SMD=–0.73), topiramate (SMD=–0.72), d‐fenfluramine (SMD=–0.54) and metformin (SMD=–0.53). Regarding waist circumference reduction, aripiprazole augmentation (SMD=–1.10) and topiramate (SMD=–0.69) demonstrated the best evidence, followed by dietary interventions (SMD=–0.39). Dietary interventions were the only to significantly improve (diastolic) blood pressure (SMD=–0.39). Switching from olanzapine to quetiapine or aripiprazole (SMD=–0.71) and metformin (SMD=–0.65) demonstrated best efficacy for reducing glucose levels, followed by glucagon‐like peptide‐1 receptor agonists (SMD=–0.39), dietary interventions (SMD=–0.37) and aripiprazole augmentation (SMD=–0.34), whereas insulin resistance improved the most with metformin (SMD=–0.75) and rosiglitazone (SMD=–0.44). Topiramate had the greatest efficacy for triglycerides (SMD=–0.68) and low‐density lipoprotein (LDL)‐cholesterol (SMD=–0.80), whereas metformin had the greatest beneficial effects on total cholesterol (SMD=–0.51) and high‐density lipoprotein (HDL)‐cholesterol (SMD=0.45). Lifestyle interventions yielded small effects for triglycerides, total cholesterol and LDL‐cholesterol (SMD=–0.35 to –0.37). Only exercise interventions increased exercise capacity (SMD=1.81). Despite frequent physical comorbidities and premature mortality mainly due to these increased physical health risks, the current evidence for pharmacological and non‐pharmacological interventions in people with schizophrenia to prevent and treat these conditions is still limited and more larger trials are urgently needed.     

Insect morphometry is reproducible under average investigation standards

1. Morphometric research is being applied to a growing number and variety of organisms. Discoveries achieved via morphometric approaches are often considered highly transferable, in contrast to the tacit and idiosyncratic interpretation of discrete character states. The reliability of morphometric workflows in insect systematics has never been a subject of focused research, but such studies are sorely needed. In this paper, we assess the reproducibility of morphometric studies of ants where the mode of data collection is a shared routine.
2. We compared datasets generated by eleven independent gaugers, that is, collaborators, who measured 21 continuous morphometric traits on the same pool of individuals according to the same protocol. The gaugers possessed a wide range of morphometric skills, had varying expertise among insect groups, and differed in their facility with measuring equipment. We used intraclass correlation coefficients (ICC) to calculate repeatability and reproducibility values (i.e., intra‐ and intergauger agreements), and we performed a multivariate permutational multivariate analysis of variance (PERMANOVA) using the Morosita index of dissimilarity with 9,999 iterations.
3. The calculated average measure of intraclass correlation coefficients of different gaugers ranged from R = 0.784 to R = 0.9897 and a significant correlation was found between the repeatability and the morphometric skills of gaugers (p = 0.016). There was no significant association with the magnification of the equipment in the case of these rather small ants. The intergauger agreement, that is the reproducibility, varied between R = 0.872 and R = 0.471 (mean R = 0.690), but all gaugers arrived at the same two‐species conclusion. A PERMANOVA test revealed no significant gauger effect on species identity (R² = 0.69, p = 0.58).
4. Our findings show that morphometric studies are reproducible when observers follow the standard protocol; hence, morphometric findings are widely transferable and will remain a valuable data source for alpha taxonomy.

     

Remodeling of Fibrous Extracellular Matrices by Contractile Cells: Predictions from Discrete Fiber Network Simulations

Contractile forces exerted on the surrounding extracellular matrix (ECM) lead to the alignment and stretching of constituent fibers within the vicinity of cells. As a consequence, the matrix reorganizes to form thick bundles of aligned fibers that enable force transmission over distances larger than the size of the cells. Contractile force-mediated remodeling of ECM fibers has bearing on a number of physiologic and pathophysiologic phenomena. In this work, we present a computational model to capture cell-mediated remodeling within fibrous matrices using finite element–based discrete fiber network simulations. The model is shown to accurately capture collagen alignment, heterogeneous deformations, and long-range force transmission observed experimentally. The zone of mechanical influence surrounding a single contractile cell and the interaction between two cells are predicted from the strain-induced alignment of fibers. Through parametric studies, the effect of cell contractility and cell shape anisotropy on matrix remodeling and force transmission are quantified and summarized in a phase diagram. For highly contractile and elongated cells, we find a sensing distance that is ten times the cell size, in agreement with experimental observations.     

Systematic bias and the phylogeny of Coleoptera—A response to Cai et al. (2022) following the responses to Cai et al. (2020)

Systematic bias is one of the major phylogenetic issues arising over the last two decades. Using methods designed to reduce compositional and rate heterogeneity, hence systematic bias, Cai and co-workers (2022) (= CEA22) reanalyzed the DNA sequence dataset for Coleoptera of Zhang et al. (2018) (= ZEA). CEA22 suggest that their phylogenetic results and major evolutionary hypotheses about the Coleoptera should be favoured over other recently published studies. Here, we discuss the methodology of CEA22 with particular attention to how their perfunctory reanalysis of ZEA obfuscates rather than illuminates beetle phylogeny. Similar to published rebuttals of an earlier study of theirs, we specifically find that many of their claims are misleading, unsupported, or false. Critically, CEA22 fail to establish the stated premise for their reanalysis. They fail to demonstrate how composition or rate heterogeneity supposedly impacted the phylogeny estimate of ZEA, let alone the results of other recent studies. Moreover, despite their claim of comprehensive sampling of Coleoptera, their dataset is neither the most diverse with respect to species and higher taxa included, nor anywhere near the largest in terms of sequence data and sampled loci. Although CEA22 does contribute additional fossils for calibration, those seeking the best available estimate for Coleoptera phylogeny and evolution based on molecular data are advised to look elsewhere.     

Light and dissolved nutrients mediate recalcitrant organic matter decomposition via microbial priming in experimental streams

1. Environmental factors such as nutrient and light availability may play important roles in determining the magnitude and direction of microbial priming and detrital decomposition and, therefore, the relative importance of microbial priming in carbon (C) dynamics in freshwater ecosystems.
2. We integrated light availability with an existing conceptual model predicting the magnitude of the priming effect (PE) along a dissolved nutrient gradient (i.e. nutrient PE model). Our modified light-nutrient PE model hypothesises how light may mediate priming at any given nutrient concentration and provides a calculation method for quantitative PE values (i.e. light effect size at a given nutrient concentration).
3. We used recirculating stream mesocosms with Quercus stellata (post oak) leaf litter as an organic matter (OM) substrate in a 150-day experiment to test our model predictions. We manipulated light levels [ambient (full light), shaded (c. 19% of ambient)] and phosphorus (P) concentration (10, 100, 500 µg PO₄-P/L) in a fully factorial design. We also supplied all mesocosms with 500 µg/L dissolved inorganic nitrogen. Microbial biomass, water column dissolved organic C, and leaf litter dry mass and recalcitrant OM [i.e. the fibre (cellulose + lignin) component of post oak substrate] were measured. Recalcitrant OM (ROM) k-rates (day⁻¹) were used to calculate the light effect size within P treatments as a log response ratio (ln[ambient k-rate/shade k-rate]) to ascertain PE magnitude and direction (positive or negative).
4. Light was an important driver of dissolved organic C, a potential source of additional labile organic matter essential for priming heterotrophic microbes. There were weak PEs in total leaf litter dry mass remaining, but PEs were more pronounced in leaf litter ROM remaining. The strongest positive PEs (specific to litter ROM pools) occur in the highest P treatment, presumably due to a change in which nutrient, nitrogen versus P, was a limiting factor for microbes based on nutrient ratios rather than P concentration alone. These results illustrate the importance of considering light levels, nutrient ratios (rather than individual nutrients), and detrital ROM components in further PE model development.