Non-climatic thermal adaptation: implications for species' responses to climate warming

Abstract

There is considerable interest in understanding how ectothermic animals may physiologically and behaviourally buffer the effects of climate warming. Much less consideration is being given to how organisms might adapt to nonclimatic heat sources in ways that could confound predictions for responses of species and communities to climate warming. Although adaptation to non-climatic heat sources (solar and geothermal) seems likely in some marine species, climate warming predictions for marine ectotherms are largely based on adaptation to climatically relevant heat sources (air or surface sea water temperature). Here, we show that non-climatic solar heating underlies thermal resistance adaptation in a rocky-eulittoralfringe snail. Comparisons of the maximum temperatures of the air, the snail's body and the rock substratum with solar irradiance and physiological performance show that the highest body temperature is primarily controlled by solar heating and re-radiation, and that the snail's upper lethal temperature exceeds the highest climatically relevant regional air temperature by approximately 228 8 8 8 8C. Non-climatic thermal adaptation probably features widely among marine and terrestrial ectotherms and because it could enable species to tolerate climatic rises in air temperature, it deserves more consideration in general and for inclusion into climate warming models.

Topographic complexity and landscape ­temperature patterns create a dynamic habitat structure on a rocky intertidal shore

“…This was because previous research (e.g. Harley & Helmuth 2003, Marshall et al 2010 suggests that the thermal ameliorating effect of habitat structure may be more pronounced (1) at the Platforms site because it is less exposed to wind and wave splash and (2) in the upper tidal strata because it is exposed to solar heating for longer. Because multiple body-size measurements were available for each measure of habitat structure (i.e.…”

“…Rock surface temperature is strongly related to thermal and desiccation stress experienced by invertebrates (Vermeij 1971, Marshall et al 2010, and thus the temperature of microhabitats relative to adjacent bare rock plays an important role in determining habitat associations (Garrity 1984, Jones & Boulding 1999, Harley & Helmuth 2003. We measured the temperature of the rock surface at 5 random points (each covering ~0.1 cm 2 ) within each quadrat using a non-contact infrared thermometer (Digitech dual-IR) to an accuracy of < 0.5°C.…”

Heat-resistant cytosolic malate dehydrogenases (cMDHs) of thermophilic intertidal snails (genus Echinolittorina): protein underpinnings of tolerance to body temperatures reaching 55°C

“…Littorine gastropods are among the dominant macrobenthos on the high intertidal shore throughout temperate and tropical oceans (Reid et al, 2006(Reid et al, , 2007. They experience prolonged emersion periods during neap tides, as well as extreme environmental temperatures over 50°C in the case of Echinolittorina species (Williams and Morritt, 1995;Uglow and Williams, 2001;Marshall et al, 2010). Snails of the genus Echinolittorina are distributed widely on the high intertidal shore and exhibit high upper thermal limits (>55°C) and a series of behavioral, morphological, physiological and biochemical responses to cope with thermal stresses Wang et al, 2016;Li, 2012;Wong, 2013).…”

Micro-scale environmental variation amplifies physiological variation among individual mussels

“…Further complexity arises when considering the often substantial degree of micro-scale variation in how individual organisms experience their environment [4,11], a pattern that likely interacts with genetic variation to contribute to variation among individuals in the physiological capacity to cope with environmental variation. In the context of thermal stress, such considerations have fostered a renewed emphasis on the causes and consequences of spatial and temporal patterns of variation in body temperature per se, in lieu of reliance on habitat temperatures and 'climate envelopes' [12,13].…”