Imperial College London

Dr Samraat Pawar

Faculty of Natural SciencesDepartment of Life Sciences (Silwood Park)

Reader in Theoretical Ecology



+44 (0)20 7594 2213s.pawar CV




2.4KennedySilwood Park






BibTex format

author = {Dell, AI and Pawar, S and Savage, VM},
doi = {10.1073/pnas.1015178108},
journal = {Proceedings of the National Academy of Sciences of the United States of America},
pages = {10591--10596},
title = {Systematic variation in the temperature dependence of physiological and ecological traits},
url = {},
volume = {108},
year = {2011}

RIS format (EndNote, RefMan)

AB - To understand the effects of temperature on biological systems, we compile, organize, and analyze a database of 1,072 thermal responses for microbes, plants, and animals. The unprecedented diversity of traits (n = 112), species (n = 309), body sizes (15 orders of magnitude), and habitats (all major biomes) in our database allows us to quantify novel features of the temperature response of biological traits. In particular, analysis of the rising component of within-species (intraspecific) responses reveals that 87% are fit well by the Boltzmann–Arrhenius model. The mean activation energy for these rises is 0.66 ± 0.05 eV, similar to the reported across-species (interspecific) value of 0.65 eV. However, systematic variation in the distribution of rise activation energies is evident, including previously unrecognized right skewness around a median of 0.55 eV. This skewness exists across levels of organization, taxa, trophic groups, and habitats, and it is partially explained by prey having increased trait performance at lower temperatures relative to predators, suggesting a thermal version of the life-dinner principle—stronger selection on running for your life than running for your dinner. For unimodal responses, habitat (marine, freshwater, and terrestrial) largely explains the mean temperature at which trait values are optimal but not variation around the mean. The distribution of activation energies for trait falls has a mean of 1.15 ± 0.39 eV (significantly higher than rises) and is also right-skewed. Our results highlight generalities and deviations in the thermal response of biological traits and help to provide a basis to predict better how biological systems, from cells to communities, respond to temperature change.
AU - Dell,AI
AU - Pawar,S
AU - Savage,VM
DO - 10.1073/pnas.1015178108
EP - 10596
PY - 2011///
SN - 1091-6490
SP - 10591
TI - Systematic variation in the temperature dependence of physiological and ecological traits
T2 - Proceedings of the National Academy of Sciences of the United States of America
UR -
UR -
VL - 108
ER -