Macrophysiology for decision‐making

Abstract

In an 1854 lecture, TH Huxley suggested that physiology should be measured by its contribution to science, its practical worth and the extent to which it should be made a branch of education. Since macrophysiology, or the investigation of variation in physiological traits over large geographical and temporal scales and the ecological implications of this variation, is well‐established and approaching its third decade, these questions are posed for it here. The field is, of course, much older, but, over the last two decades, has contributed substantially to fundamental eco‐evolutionary research and to understanding the conservation consequences of physiological variation at regional and global scales. Its greatest successes have been in understanding variation in thermal and metabolic responses of animals and plants to variable environments and the significance thereof in the context of the climate crisis. By contrast, much less progress has been made in understanding the regulation of water in the context of currently changing environments and projections of further impacts associated with ongoing global change. The development of new datasets of physiological traits across broad spatial scales has been a slower enterprise than the further compilation of trait databases from extant data. Surprising insights have emerged from genomics‐based microbial macrophysiology, an approach which has much potential to span all of life's variety. The findings of macrophysiological investigations have been taken up within policy reports and/or implementation actions, such as those of the IPCC and the Antarctic Treaty System, that have resulted in benefits to society and to the environment. Yet, as is the case with other areas of research, much remains to be done to develop further strategies to counteract the anti‐science attitudes that are now so prevalent globally.

Global thermal tolerance of freshwater invertebrates and fish

“…Thermal limits of life have interested researchers since at least the 1700s [1][2][3][4][5] , with early comparisons of thermal tolerances between organisms published in the late 1800s 3 . Despite the large volume of research on the biological and ecological influence of temperature in the last two centuries, many questions regarding thermal tolerances remain unanswered [6][7][8] . For example, the relationship between oxygen and thermal tolerance is still contested 9,10 , and the influence of thermal tolerance on range limits not fully understood 11,12 .…”

What do molecular laws of life mean for species: absolute restrictions or mere suggestions?

“…The narrow variation is also relevant for tests of whether particular laws can limit the performance of individuals and their capacity to deal with environmental or climatic changes, for example. Thus, the uniformity of molecular laws of lifeor the lack thereofis directly related to the more general problem of macrophysiology, that is, variations in physiological traits over large geographical and temporal scales (Chown et al, 2004;Chown, 2023). Finally, such uniformity may have direct, practical benefits for scientists; if a simple molecular parameter quantified in a small sample represents a reliable index of a complex parameter in a wide array of individuals, it could allow for more feasible and sometimes also more ethical studies; for example, in finding potential links between molecular factors in the blood and whole-body metabolic rates (Malkoc et al, 2021;Holden et al, 2022).…”