Climate-mediated shifts in temperature fluctuations promote extinction risk

Abstract

Climate-mediated changes in thermal stress can destabilize animal populations and promote extinction risk. However, risk assessments often focus on changes in mean temperatures and thus ignore the role of temporal variability or structure. Using Earth System Model projections, we show that significant regional differences in the statistical distribution of temperature will emerge over time and give rise to shifts in the mean, variability and persistence of thermal stress. Integrating these trends into mathematical models that simulate the dynamical and cumulative effects of thermal stress on the performance of 38 globally distributed ectotherm species revealed complex regional changes in population stability over the twenty-first century, with temperate species facing higher risk. Yet despite their idiosyncratic effects on stability, projected temperatures universally increased extinction risk. Overall, these results show that the effects of climate change may be more extensive than previously predicted on the basis of the statistical relationship between biological performance and average temperature.

Variation in temperature of peak trait performance constrains adaptation of arthropod populations to climatic warming

“…Previous work has focused on the effect of thermal sensitivity (E, Fig. 1B, SM Table 1) ( 13 , 14 ) or upper lethal thermal limit ( CT max ) ( 15 – 17 ) of traits on the temperature-dependence of r m , providing insights into the responses of populations to short-term thermal fluctuations and heat waves on populations ( 18 – 20 ). However, to understand how populations will respond to long-term sustained climatic warming, we need to quantify the adaptive potential of the temperature at which fitness peaks with respect to temperature ( T opt ) as well as the r m achieved at that temperature (“thermal fitness”; Fig.…”

“…In our theory, this pattern arises through thermodynamic constraints on life history traits built into the Sharpe-Schoolfield equation for TPCs (SM Eqn 3), which focuses on a single, rate-limiting enzyme underlying metabolic rate ( 26 ). While previous theoretical work has sought to understand the evolutionary basis and consequences of the hotter-is-better phenomenon ( 10 , 15 , 19 , 22 , 25 , 27 ), to the best of our knowledge, this is the first time that the contributions of underlying traits to it have been quantified.…”

Towards complex applications of active remote sensing for ecology and conservation

“…Thermal stress induced by climatic changes recently has been reported to undermine animal populations and increase their risk of extinction (e.g. Duffy et al, 2022; Sergio et al, 2018). Earlier remote sensing studies have largely focused on vegetation proxies extracted from optical multispectral data (e.g.…”

Tropical high-altitude insects show limited capacity to handle high temperatures

“…Rising global temperatures raise alarms of extinction for several species which are unable to adapt to climate change at shorter time scales (Turney, Ausseil et al 2020, Habibullah, Din et al 2022). Rising temperatures aside, variability in temperatures is also a confounding factor increasing the complexity of assessing the impact of climate change (Duffy, Gouhier et al 2022) as diverse zones face different climatic regimes. Temperature rise in tropics was considered to be lower than in temperate or polar regions, recent climate models strongly predict tropical zones of Amazonia, Sahel, South-east Asia and India to face increased warming (Holmes, Woollings et al 2016, Bathiany, Dakos et al 2018).…”

“…Ectotherms regulate their body temperatures based on the external environment (Hertz, Huey et al 1993) and are ideal to study thermal responses to changing climate and several species are known to be impacted by climate (Duffy, Gouhier et al 2022). Insects as notable ectotherms; are seen to exhibit tremendous populations declines (Halsch, Shapiro et al 2021).…”