scholarly journals Use and misuse of temperature normalisation in meta-analyses of thermal responses of biological traits

2017 ◽  
Author(s):  
Dimitrios - Georgios Kontopoulos ◽  
Bernardo García-Carreras ◽  
Sofía Sal ◽  
Thomas P. Smith ◽  
Samraat Pawar
Keyword(s):  
Climate Change ◽  
Thermal Performance ◽  
Alternative Methods ◽  
Biological Traits ◽  
Thermal Physiology ◽  
Wide Range ◽  
Performance Curves ◽  
Biological Impacts ◽  
Using Data ◽  
Meta Analyses

There is currently unprecedented interest in quantifying variation in thermal physiology among organisms in order to understand and predict the biological impacts of climate change. A key parameter in this quantification of thermal physiology is the performance or value of a trait, across individuals or species, at a common temperature (temperature normalisation). An increasingly popular model for fitting thermal performance curves to data – the Sharpe-Schoolfield equation – can yield strongly inflated estimates of temperature-normalised trait values. These deviations occur whenever a key thermodynamic assumption of the model is violated, i.e. when the enzyme governing the performance of the trait is not fully functional at the chosen reference temperature. Using data on 1,758 thermal performance curves across a wide range of species, we identify the conditions that exacerbate this inflation. We then demonstrate that these biases can compromise tests to detect metabolic cold adaptation, which requires comparison of fitness or trait performance of different species or genotypes at some fixed low temperature. Finally, we suggest alternative methods for obtaining unbiased estimates of temperature-normalised trait values for meta-analyses of thermal performance across species in climate change impact studies.

scholarly journals Use and misuse of temperature normalisation in meta-analyses of thermal responses of biological traits

2017 ◽  
Author(s):  
Dimitrios - Georgios Kontopoulos ◽  
Bernardo García-Carreras ◽  
Sofía Sal ◽  
Thomas P. Smith ◽  
Samraat Pawar
Keyword(s):  
Climate Change ◽  
Thermal Performance ◽  
Alternative Methods ◽  
Biological Traits ◽  
Thermal Physiology ◽  
Wide Range ◽  
Performance Curves ◽  
Biological Impacts ◽  
Using Data ◽  
Meta Analyses

There is currently unprecedented interest in quantifying variation in thermal physiology among organisms in order to understand and predict the biological impacts of climate change. A key parameter in this quantification of thermal physiology is the performance or value of a trait, across individuals or species, at a common temperature (temperature normalisation). An increasingly popular model for fitting thermal performance curves to data – the Sharpe-Schoolfield equation – can yield strongly inflated estimates of temperature-normalised trait values. These deviations occur whenever a key thermodynamic assumption of the model is violated, i.e. when the enzyme governing the performance of the trait is not fully functional at the chosen reference temperature. Using data on 1,758 thermal performance curves across a wide range of species, we identify the conditions that exacerbate this inflation. We then demonstrate that these biases can compromise tests to detect metabolic cold adaptation, which requires comparison of fitness or trait performance of different species or genotypes at some fixed low temperature. Finally, we suggest alternative methods for obtaining unbiased estimates of temperature-normalised trait values for meta-analyses of thermal performance across species in climate change impact studies.

scholarly journals Use and misuse of temperature normalisation in meta-analyses of thermal responses of biological traits

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e4363 ◽  
Author(s):  
Dimitrios - Georgios Kontopoulos ◽  
Bernardo García-Carreras ◽  
Sofía Sal ◽  
Thomas P. Smith ◽  
Samraat Pawar
Keyword(s):  
Climate Change ◽  
Thermal Performance ◽  
Alternative Methods ◽  
Biological Traits ◽  
Thermal Physiology ◽  
Wide Range ◽  
Performance Curves ◽  
Biological Impacts ◽  
Using Data ◽  
Meta Analyses

There is currently unprecedented interest in quantifying variation in thermal physiology among organisms, especially in order to understand and predict the biological impacts of climate change. A key parameter in this quantification of thermal physiology is the performance or value of a rate, across individuals or species, at a common temperature (temperature normalisation). An increasingly popular model for fitting thermal performance curves to data—the Sharpe-Schoolfield equation—can yield strongly inflated estimates of temperature-normalised rate values. These deviations occur whenever a key thermodynamic assumption of the model is violated, i.e., when the enzyme governing the performance of the rate is not fully functional at the chosen reference temperature. Using data on 1,758 thermal performance curves across a wide range of species, we identify the conditions that exacerbate this inflation. We then demonstrate that these biases can compromise tests to detect metabolic cold adaptation, which requires comparison of fitness or rate performance of different species or genotypes at some fixed low temperature. Finally, we suggest alternative methods for obtaining unbiased estimates of temperature-normalised rate values for meta-analyses of thermal performance across species in climate change impact studies.

scholarly journals rTPC and nls.multstart: a new pipeline to fit thermal performance curves in R

2020 ◽  
Author(s):  
Daniel Padfield ◽  
Hannah O’Sullivan ◽  
Samraat Pawar
Keyword(s):  
Climate Change ◽  
Model Selection ◽  
Thermal Performance ◽  
Model Fitting ◽  
Multiple Models ◽  
List Type ◽  
Linear Least Squares ◽  
Wide Range ◽  
Performance Curves ◽  
Weighted Model

AbstractThe quantification of thermal performance curves (TPCs) for biological rates has many applications to problems such as predicting species’ responses to climate change. There is currently no widely used open-source pipeline to fit mathematical TPC models to data, which limits the transparency and reproducibility of the curve fitting process underlying applications of TPCs.We present a new pipeline in R that currently allows for reproducible fitting of 24 different TPC models using non-linear least squares (NLLS) regression. The pipeline consists of two packages – rTPC and nls. multstart – that allow multiple start values for NLLS fitting and provides helper functions for setting start parameters. This pipeline overcomes previous problems that have made NLLS fitting and estimation of key parameters difficult or unreliable.We demonstrate how rTPC and nls.multstart can be combined with other packages in R to robustly and reproducibly fit multiple models to multiple TPC datasets at once. In addition, we show how model selection or averaging, weighted model fitting, and bootstrapping can easily be implemented within the pipeline.This new pipeline provides a flexible and reproducible approach that makes the challenging task of fitting multiple TPC models to data accessible to a wide range of users.

scholarly journals Thermal physiology and thermoregulatory behaviour exhibit low heritability despite genetic divergence between lizard populations

2018 ◽  
Vol 285 (1878) ◽  
pp. 20180697 ◽  
Author(s):  
Michael L. Logan ◽  
John David Curlis ◽  
Anthony L. Gilbert ◽  
Donald B. Miles ◽  
Albert K. Chung ◽  
...  
Keyword(s):  
Thermal Performance ◽  
Genetic Divergence ◽  
Common Garden ◽  
Response To Selection ◽  
Thermal Physiology ◽  
Evolutionary Potential ◽  
Thermal Environments ◽  
Performance Curves ◽  
Brown Anole ◽  
Thermoregulatory Behaviour

Ectothermic species are particularly sensitive to changes in temperature and may adapt to changes in thermal environments through evolutionary shifts in thermal physiology or thermoregulatory behaviour. Nevertheless, the heritability of thermal traits, which sets a limit on evolutionary potential, remains largely unexplored. In this study, we captured brown anole lizards ( Anolis sagrei ) from two populations that occur in contrasting thermal environments. We raised offspring from these populations in a laboratory common garden and compared the shape of their thermal performance curves to test for genetic divergence in thermal physiology. Thermal performance curves differed between populations in a common garden in ways partially consistent with divergent patterns of natural selection experienced by the source populations, implying that they had evolved in response to selection. Next, we estimated the heritability of thermal performance curves and of several traits related to thermoregulatory behaviour. We did not detect significant heritability in most components of the thermal performance curve or in several aspects of thermoregulatory behaviour, suggesting that contemporary selection is unlikely to result in rapid evolution. Our results indicate that the response to selection may be slow in the brown anole and that evolutionary change is unlikely to keep pace with current rates of environmental change.

scholarly journals Can we predict ectotherm responses to climate change using thermal performance curves and body temperatures?

2016 ◽  
Vol 19 (11) ◽  
pp. 1372-1385 ◽  
Author(s):  
Brent J. Sinclair ◽  
Katie E. Marshall ◽  
Mary A. Sewell ◽  
Danielle L. Levesque ◽  
Christopher S. Willett ◽  
...  
Keyword(s):  
Climate Change ◽  
Thermal Performance ◽  
Body Temperatures ◽  
Performance Curves

A MODELING SYSTEM FOR CLIMATE CHANGE RISK ASSESSMENT, MANAGEMENT AND HEDGING IN COASTAL AREAS

2017 ◽  
Author(s):  
Sergei Soldatenko ◽  
Sergei Soldatenko ◽  
Genrikh Alekseev ◽  
Genrikh Alekseev ◽  
Alexander Danilov ◽  
...  
Keyword(s):  
Climate Change ◽  
Risk Assessment ◽  
Coastal Areas ◽  
Mitigation Strategies ◽  
System Structure ◽  
The Arctic ◽  
Risk Modeling ◽  
Wide Range ◽  
Adverse Weather ◽  
The Impact

Every aspect of human operations faces a wide range of risks, some of which can cause serious consequences. By the start of 21st century, mankind has recognized a new class of risks posed by climate change. It is obvious, that the global climate is changing, and will continue to change, in ways that affect the planning and day to day operations of businesses, government agencies and other organizations and institutions. The manifestations of climate change include but not limited to rising sea levels, increasing temperature, flooding, melting polar sea ice, adverse weather events (e.g. heatwaves, drought, and storms) and a rise in related problems (e.g. health and environmental). Assessing and managing climate risks represent one of the most challenging issues of today and for the future. The purpose of the risk modeling system discussed in this paper is to provide a framework and methodology to quantify risks caused by climate change, to facilitate estimates of the impact of climate change on various spheres of human activities and to compare eventual adaptation and risk mitigation strategies. The system integrates both physical climate system and economic models together with knowledge-based subsystem, which can help support proactive risk management. System structure and its main components are considered. Special attention is paid to climate risk assessment, management and hedging in the Arctic coastal areas.

Classical and modern drug extraction techniques: facts and figures

2017 ◽  
Vol 2 (4) ◽  
Author(s):  
Bharti Umrethia ◽  
Bharat Kalsariya ◽  
Prof. P. U. Vaishnav
Keyword(s):  
Solvent Extraction ◽  
Dosage Forms ◽  
Herbal Extract ◽  
Alternative Methods ◽  
Extraction Techniques ◽  
Modern Drug ◽  
Novel Drugs ◽  
Wide Range ◽  
In The Mists ◽  
Heating Pattern

In present era, herbal extract succeeds inimitable place in pharmaceutical science. In view back the earliest extraction techniques are lost in the mists of history. As time went the plants have been processed by grinding, boiling or immersing. The systemic presentation of Ayurvedic extraction system has been first time familiarized by Acharya Charaka as Panchavidha Kashaya Kalpana (five basic primary dosage forms) and based upon these primary dosage forms, secondary dosage forms are developed by using different heating pattern for extraction of pharmacological active ingredients. The administration of these dosage forms is mainly dependent on the Bala (strength) of Vyadhi (disease) and Atura (patient). Due to increased demand of Ayurvedic medicines and industrialization, the transformation of classical dosage forms takes place by implanting a wide range of technologies with different methods of extraction include conventional techniques such as maceration, percolation, infusion, decoction, hot continuous extraction etc. and recently, alternative methods like ultrasound assisted solvent extraction (UASE), microwave assisted solvent extraction (MASE) and supercritical fluid extractions (SFE). The extract obtained by these procedure uses as a large source of therapeutic phyto-chemicals that may lead to the development of novel drugs. Essentially, the purpose behind this changing face in both the extraction systems are different but can say that it is a new insight from ancient essence.

The Biology of Mediterranean-Type Ecosystems

2018 ◽  
Author(s):  
Karen J. Esler ◽  
Anna L. Jacobsen ◽  
R. Brandon Pratt
Keyword(s):  
Climate Change ◽  
South Africa ◽  
Invasive Species ◽  
Habitat Loss ◽  
Endemic Species ◽  
Geographic Area ◽  
Cutting Edge ◽  
Wide Range ◽  
The Mediterranean ◽  
Mediterranean Type Ecosystems

The world’s mediterranean-type climate regions (including areas within the Mediterranean, South Africa, Australia, California, and Chile) have long been of interest to biologists by virtue of their extraordinary biodiversity and the appearance of evolutionary convergence between these disparate regions. Comparisons between mediterranean-type climate regions have provided important insights into questions at the cutting edge of ecological, ecophysiological and evolutionary research. These regions, dominated by evergreen shrubland communities, contain many rare and endemic species. Their mild climate makes them appealing places to live and visit and this has resulted in numerous threats to the species and communities that occupy them. Threats include a wide range of factors such as habitat loss due to development and agriculture, disturbance, invasive species, and climate change. As a result, they continue to attract far more attention than their limited geographic area might suggest. This book provides a concise but comprehensive introduction to mediterranean-type ecosystems. As with other books in the Biology of Habitats Series, the emphasis in this book is on the organisms that dominate these regions although their management, conservation, and restoration are also considered.

Sign in / Sign up

Export Citation Format

Share Document