Physiological Responses to Elevated Temperature across the Geographic Range of a Terrestrial Salamander

Widespread species often possess physiological mechanisms for coping with thermal heterogeneity, and uncovering these mechanisms provides insight into species responses to climate change. The emergence of non-invasive corticosterone (CORT) assays allows us to rapidly assess physiological responses to environmental change on a large scale. We lack, however, a basic understanding of how temperature affects CORT, and whether temperature and CORT interactively affect performance. Here, we examine the effects of elevated temperature on CORT and whole-organism performance in a terrestrial salamander, Plethodon cinereus, across a latitudinal gradient. Using water-borne hormone assays, we found that raising ambient temperature from 15 to 25°C increased CORT release at a similar rate for salamanders from all sites. However, CORT release rate was higher overall in the warmest, southernmost site. Elevated temperatures also affected physiological performance, but the effects differed among sites. Ingestion rate increased in salamanders from the warmer sites but remained the same for those from cooler sites. Mass gain was reduced for most individuals, though this reduction was more dramatic in salamanders from the cooler sites. We also found a temperature-dependent relationship between CORT and food conversion efficiency (i.e., the amount of mass gained per unit food ingested). CORT was negatively related to food conversion efficiency at 25°C but was unrelated at 15°C. Thus, the energetic gains of elevated ingestion rates may be counteracted by elevated CORT release rates experienced by salamanders in warmer environments. By integrating multiple physiological metrics, we highlight the complex relationships between temperature and individual responses to warming climates

Data from: Salamander climbing behavior varies among species and is correlated with community composition

Species coexistence is often facilitated by behavioral strategies that minimize competition for limited resources. Terrestrial, lungless salamanders (genus Plethodon) coexist in predictable assemblages of body size guilds, but little is known about the behavioral mechanisms that promote such coexistence. Here, we considered the hypothesis that Plethodon salamanders use climbing behavior to reduce competitive interactions, thereby promoting coexistence through spatial partitioning. To explore this hypothesis, we quantified the frequency of climbing behavior at field sites where small-bodied (P. cinereus) and large-bodied (P. glutinosus) species are always present, but an intermediate-bodied species (P. montanus) is either absent, introduced, or native. We observed that climbing behavior varied among size guilds so that the smallest species climbed most frequently, followed by the intermediate, and then the large species. Further, we identified several correlates of climbing behavior that may be shaped by intraspecific and interspecific competition. Climbing frequency was positively correlated with intraspecific competition and negatively correlated with interspecific competition in the small species, unrelated to competition in the intermediate species, and positively correlated with interspecific competition in the large species. Our results suggest that Plethodon size guilds might differentially utilize climbing behavior to facilitate spatial partitioning in dense populations and communities. Further, we show how competition intensity can shape the behavior of cohabitating species, and ultimately provide insight into how behavioral plasticity and microhabitat partitioning can promote species coexistence

Physiological measurements in the eastern red-backed salamander - corticosterone release rate and thermal performance

Data was collected in the laboratory using field-collected salamanders (Plethodon cinereus) from 4 study sites in ME, NY, MD, and VA. The file was created using Microsoft Excel. The column headings are as follows: experiment (indicates which of the physiological studies the data corresponds to); site code (indicates the state of origin); site name (specifies the collection site); site heat value (refers to the mean daily maximum temperature at the collection site as explained in the associated manuscript); salamander ID (a unique code given to each study animal); experimental temp (15 or 25°C as explained in the associated manuscript); sex (m or f); svl (snout-vent length measured to posterior edge of cloaca); tail length (measured from posterior edge of cloaca); total length (svl + tail length); mass (refers to the mass recorded at the time of corticosterone sampling); corticosterone release rate (see associated manuscript for methodology); performance initial mass (refers to the mass recorded at the start of each thermal performance trial); performance final mass (refers to the mass at the end of each performance trial); days between mass (refers to the number of days that passed between initial and final mass events); performance (% change in mass/day); ingestion (total number of flies consumed/day during performance trial)

Data from: Physiological responses to elevated temperature across the geographic range of a terrestrial salamander

Widespread species often possess physiological mechanisms for coping with thermal heterogeneity, and uncovering these mechanisms provides insight into species responses to climate change. The emergence of non-invasive corticosterone (CORT) assays allows us to rapidly assess physiological responses to environmental change on a large scale. We lack, however, a basic understanding of how temperature affects CORT, and whether temperature and CORT interactively affect performance. Here, we examine the effects of elevated temperature on CORT and whole-organism performance in a terrestrial salamander, Plethodon cinereus, across a latitudinal gradient. Using water-borne hormone assays, we found that raising ambient temperature from 15 to 25&[deg]C increased CORT release at a similar rate for salamanders from all sites. However, CORT release rate was higher overall in the warmest, southernmost site. Elevated temperatures also affected physiological performance, but the effects differed among sites. Ingestion rate increased in salamanders from the warmer sites but remained the same for those from cooler sites. Mass gain was reduced for most individuals, though this reduction was more dramatic in salamanders from the cooler sites. We also found a temperature-dependent relationship between CORT and food conversion efficiency (i.e., the amount of mass gained per unit food ingested). CORT was negatively related to food conversion efficiency at 25&[deg]C but was unrelated at 15&[deg]C. Thus, the energetic gains of elevated ingestion rates may be counteracted by elevated CORT release rates experienced by salamanders in warmer environments. By integrating multiple physiological metrics, we highlight the complex relationships between temperature and individual responses to warming climates

Management development: a literature review and implications for future research – Part I: Conceptualisations and Practices

Interest in management development is mushrooming. The number of articles which address different aspects of it are likewise increasing apace. This has heightened the need for a broad-based review which will pull the material together, give shape to it, evaluate it and draw out its implications. In this, the first of a two-part article, this task is commenced

Pragmatic solutions to reduce the global burden of stroke: a World Stroke Organization–Lancet Neurology Commission

Stroke is the second leading cause of death worldwide. The burden of disability after a stroke is also large, and is increasing at a faster pace in low-income and middle-income countries than in high-income countries. Alarmingly, the incidence of stroke is increasing in young and middle-aged people (ie, age <55 years) globally. Should these trends continue, Sustainable Development Goal 3.4 (reducing the burden of stroke as part of the general target to reduce the burden of non-communicable diseases by a third by 2030) will not be met. In this Commission, we forecast the burden of stroke from 2020 to 2050. We project that stroke mortality will increase by 50%—from 6·6 million (95% uncertainty interval [UI] 6·0 million–7·1 million) in 2020, to 9·7 million (8·0 million–11·6 million) in 2050—with disability-adjusted life-years (DALYs) growing over the same period from 144·8 million (133·9 million–156·9 million) in 2020, to 189·3 million (161·8 million–224·9 million) in 2050. These projections prompted us to do a situational analysis across the four pillars of the stroke quadrangle: surveillance, prevention, acute care, and rehabilitation. We have also identified the barriers to, and facilitators for, the achievement of these four pillars. Disability-adjusted life-years (DALYs) The sum of the years of life lost as a result of premature mortality from a disease and the years lived with a disability associated with prevalent cases of the disease in a population. One DALY represents the loss of the equivalent of one year of full health On the basis of our assessment, we have identified and prioritised several recommendations. For each of the four pillars (surveillance, prevention, acute care, and rehabilitation), we propose pragmatic solutions for the implementation of evidence-based interventions to reduce the global burden of stroke. The estimated direct (ie, treatment and rehabilitation) and indirect (considering productivity loss) costs of stroke globally are in excess of US$891 billion annually. The pragmatic solutions we put forwards for urgent implementation should help to mitigate these losses, reduce the global burden of stroke, and contribute to achievement of Sustainable Development Goal 3.4, the WHO Intersectoral Global Action Plan on epilepsy and other neurological disorders (2022–2031), and the WHO Global Action Plan for prevention and control of non-communicable diseases. Reduction of the global burden of stroke, particularly in low-income and middle-income countries, by implementing primary and secondary stroke prevention strategies and evidence-based acute care and rehabilitation services is urgently required. Measures to facilitate this goal include: the establishment of a framework to monitor and assess the burden of stroke (and its risk factors) and stroke services at a national level; the implementation of integrated population-level and individual-level prevention strategies for people at any increased risk of cerebrovascular disease, with emphasis on early detection and control of hypertension; planning and delivery of acute stroke care services, including the establishment of stroke units with access to reperfusion therapies for ischaemic stroke and workforce training and capacity building (and monitoring of quality indicators for these services nationally, regionally, and globally); the promotion of interdisciplinary stroke care services, training for caregivers, and capacity building for community health workers and other health-care providers working in stroke rehabilitation; and the creation of a stroke advocacy and implementation ecosystem that includes all relevant communities, organisations, and stakeholders