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Understanding the factors affecting thermal tolerance is crucial for predicting the impact climate change will have on ectotherms. However, the role developmental plasticity plays in allowing populations to cope with thermal extremes is poorly understood. Here, we meta-analyse how thermal tolerance is initially and persistently impacted by early (embryonic and juvenile) thermal environments by using data from 150 experimental studies on 138 ectothermic species. Thermal tolerance only increased by 0.13°C per 1°C change in developmental temperature and substantial variation in plasticity (~36%) was the result of shared evolutionary history and species ecology. Aquatic ectotherms were more than three times as plastic as terrestrial ectotherms. Notably, embryos expressed weaker but more heterogenous plasticity than older life stages, with numerous responses appearing as non-adaptive. While developmental temperatures did not have persistent effects on thermal tolerance overall, persistent effects were vastly under-studied, and their direction and magnitude varied with ontogeny. Embryonic stages may represent a critical window of vulnerability to changing environments and we urge researchers to consider early life stages when assessing the climate vulnerability of ectotherms. Overall, our synthesis suggests that developmental changes in thermal tolerance rarely reach levels of perfect compensation and may provide limited benefit in changing environments.

Coral reefs are under threat from disease as climate change alters environmental conditions. Rising temperatures exacerbate coral disease, but this relationship is likely complex as other factors also influence coral disease prevalence. To better understand this relationship, we meta-analytically examined 108 studies for changes in global coral disease over time alongside temperature, expressed using average summer sea surface temperature (SST) and cumulative heat stress as weekly sea surface temperature anomalies (WSSTAs). We found both rising average summer SST and WSSTA were associated with global increases in the mean and variability in coral disease prevalence. We showed global coral disease prevalence reached 9.92% compared to 3.16% in 1992, and the effect of ‘year’ became more stable (i.e., has lower variance), contrasting to the effects of the two temperature stressors. Regional patterns diverged over time and differed in response to average summer SST. Our model predicted that, under the same trajectory, 76.8% of corals would be diseased globally by 2100, even assuming moderate average summer SST and WSSTA. These results highlight the need for urgent action to mitigate coral disease. Mitigating the impact of rising ocean temperatures on coral disease alone is a complex challenge requiring global discussion and further study.

Behavioural phenotyping is often time and labour-intensive, which can come at a cost to sample size and statistical precision. This is particularly a concern given that behaviours are often highly variable within and between individuals, so naturally requires a larger sample size. Drosophila melanogaster is a common model system in many research fields, and behavioural observations are frequently required. While D. melanogaster has a rapid lifecycle that enables large numbers of flies to be reared for experiments, they are still subject to methodological bottlenecks for behavioural observations. Additionally, their small and delicate bodies make it difficult to observe certain behaviours in real-time, for example, in movement tracking or when performing repeated assays on the same individuals. Here, we present a method, pilot data, custom data processing and analysis scripts for high-throughput behavioural phenotyping in D. melanogaster, as well as general remarks for future studies. We used automatic tracking units to measure three behaviours in the same individuals: locomotor activity, exploratory behaviour in a Y-maze, and habituation to a startle response stimulus. We then examined between-individual variation and trait correlations using our pilot data. Through this, we show that these behaviours are amenable to high-throughput automated tracking, with locomotor activity generating the most straightforward and high-quality data. These methods can be used to free up time and labour to allocate to increasing sample sizes and can be used to address a range of biological questions in ecology, evolution, and beyond.

Butterfly glioblastoma (bGBM) is a grade 4 glioma with a poor prognosis. Surgical treatment of these cancers has been reviewed in the literature with some recent studies supporting resection as a safe and effective treatment instead of biopsy and adjuvant therapy. This meta-analysis was designed to determine whether there are significant differences in overall survival (OS) and postoperative neurologic deficits (motor, speech, and cranial nerve) following intervention in patients who underwent tumor resection as part of their treatment, compared to patients who underwent biopsy without surgical resection. A literature search was conducted using PubMed (National Library of Medicine) and Embase (Elsevier) to identify articles from each database's earliest records to May 25, 2021, that directly compared the outcomes of biopsy and resection in bGBM patients and met predetermined inclusion criteria. A meta-analysis was conducted to compare the effects of the two management strategies on OS and postoperative neurologic deficits. Six articles met our study inclusion criteria. OS was found to be significantly longer for the resection group at 6 months (odds ratio [OR] 2.94, 95% confidence interval [CI] 1.23-7.05) and 12 months (OR 3.75, 95% CI 1.10-12.76) than for the biopsy group. No statistically significant differences were found in OS at 18 and 24 months. Resection was associated with an increased rate of postoperative neurologic deficit (OR 2.05, 95% CI 1.02-4.09). Resection offers greater OS up to 1 year postintervention than biopsy alone; however, this comes at the cost of higher rates of postoperative neurologic deficits.

Understanding the factors affecting thermal tolerance is crucial for predicting the impact climate change will have on ectotherms. However, the role developmental plasticity plays in allowing populations to cope with thermal extremes is poorly understood. Here, we meta-analyse how thermal tolerance is acutely and persistently impacted by early thermal environments by using data from 150 experimental studies on 138 ectothermic species. Thermal tolerance only increased by 0.13°C per 1°C change in developmental temperature and substantial variation in plasticity (~36%) was the result of shared evolutionary history and species ecology. Aquatic ectotherms were more than three times as plastic as terrestrial ectotherms. Notably, embryos expressed weaker but more heterogenous plasticity than older life stages, with numerous responses appearing as non-adaptive. While we did not find universal evidence for developmental temperatures to have persistent effects on thermal tolerance, persistent effects were vastly under-studied, and their direction and magnitude varied with ontogeny. Embryonic stages may represent a critical window of vulnerability to changing environments and we urge researchers to consider early life stages when assessing the climate vulnerability of ectotherms. Overall, our synthesis suggests that developmental changes in thermal tolerance will rarely reach levels of perfect compensation and buffer ectotherms from rising temperatures.

Meta-analysis is a powerful tool used to generate quantitatively informed answers to pressing global challenges. By distilling data from broad sets of research designs and study systems into standardised effect sizes, meta-analyses provide physiologists with opportunities to estimate overall effect sizes and understand the drivers of effect variability. Despite this ambition, research designs in the field of comparative physiology can appear, at the outset, as being vastly different to each other because of ‘nuisance heterogeneity’ (e.g. different temperatures or treatment dosages used across studies). Methodological differences across studies have led many to believe that meta-analysis is an exercise in comparing ‘apples with oranges’. Here, we dispel this myth by showing how standardised effect sizes can be used in conjunction with multilevel meta-regression models to both account for the factors driving differences across studies and make them more comparable. We assess the prevalence of nuisance heterogeneity in the comparative physiology literature – showing it is common and often not accounted for in analyses. We then formalise effect size measures (e.g. the temperature coefficient, Q10) that provide comparative physiologists with a means to remove nuisance heterogeneity without the need to resort to more complex statistical models that may be harder to interpret. We also describe more general approaches that can be applied to a variety of different contexts to derive new effect sizes and sampling variances, opening up new possibilities for quantitative synthesis. By using effect sizes that account for components of effect heterogeneity, in combination with existing meta-analytic models, comparative physiologists can explore exciting new questions while making results from large-scale data sets more accessible, comparable and widely interpretable.

Comparative analyses require researchers to not only ensure data quality, but also to make prudent and justifiable assumptions about data comparability. A failure to do so can lead to unreliable conclusions. As a case in point, we comment on a study that estimated the vulnerability of the world’s fish species to climate change using comparison between life stages (Dahlke et al. 2020, Science 369: 65-70). We highlight concerns with the data quality and argue that the metrics used to investigate ontogenetic differences in thermal tolerance were incomparable and confounded. Therefore, we provide caution when interpreting their results in the light of climate vulnerability. We suggest potential remedies and recommend thermal tolerance metrics that may be comparable across life stages. We also encourage the creation of guidelines to design, report, and assess comparative analyses to increase their reliability and reproducibility.

We propose that thoughts about one's own creativity are related to implicit views about the similarity of one’s traits to those of creative exemplars. In this study, 298 undergraduates were instructed either to imagine an example of an innovative product or to imagine themselves creating a product in one of three domains (art, music, or gadgetry). Following the manipulation, participants rated the fitness of a list of creative traits relative to their first or third person creative exemplar. Fitness ratings were generally higher for third person exemplars than for first person exemplars. Though ratings also varied by domain, there was a significant interaction between perspective and domain, such that first-person ratings (i.e., self ratings) did not vary by exemplar domain, while third-person ratings (i.e., an external exemplar) did vary by domain. Implications and future directions for the study of implicit theories and creative performance and achievement are discussed.

Persistent myofibroblast differentiation is a hallmark of fibrotic diseases. Myofibroblasts are characterized by de novo expression of alpha smooth muscle actin (αSMA) and excess fibronectin assembly. Recent studies provide conflicting reports on the effects of tyrosine kinase inhibitor dasatinib on myofibroblast differentiation and fibrosis. Also, it is not fully understood whether dasatinib modulates myofibroblast differentiation by targeting Src kinase. Herein, we investigated the effect of dasatinib on cSrc and transforming growth factor-β (TGFβ)-induced myofibroblast differentiation in vitro. Our results indicated that selective Src kinase inhibition using PP2 mimicked the effect of dasatinib in attenuating myofibroblast differentiation as evident by blunted αSMA expression and modest, but significant inhibition of fibronectin assembly in both NIH 3T3 and fibrotic human lung fibroblasts. Mechanistically, our data showed that dasatinib modulates αSMA synthesis through Src kinase-mediated modulation of serum response factor expression. Collectively, our results demonstrate that dasatinib modulates myofibroblast differentiation through Src-SRF pathway. Thus, dasatinib could potentially be a therapeutic option in fibrotic diseases.