• Energy Research

AbstractClimate change is altering phenology and distributions of many species and further changes are projected. Can species physiologically adapt to climate warming? We analyse thermal tolerances of a large number of terrestrial ectotherm (n = 697), endotherm (n = 227) and plant (n = 1816) species worldwide, and show that tolerance to heat is largely conserved across lineages, while tolerance to cold varies between and within species. This pattern, previously documented for ectotherms, is apparent for this group and for endotherms and plants, challenging the longstanding view that physiological tolerances of species change continuously across climatic gradients. An alternative view is proposed in which the thermal component of climatic niches would overlap across species more than expected. We argue that hard physiological boundaries exist that constrain evolution of tolerances of terrestrial organisms to high temperatures. In contrast, evolution of tolerances to cold should be more frequent. One consequence of conservatism of upper thermal tolerances is that estimated niches for cold‐adapted species will tend to underestimate their upper thermal limits, thereby potentially inflating assessments of risk from climate change. In contrast, species whose climatic preferences are close to their upper thermal limits will unlikely evolve physiological tolerances to increased heat, thereby being predictably more affected by warming.

Consequences of shifting species distributions Climate change is causing geographical redistribution of plant and animal species globally. These distributional shifts are leading to new ecosystems and ecological communities, changes that will affect human society. Pecl et al. review these current and future impacts and assess their implications for sustainable development goals. Science , this issue p. eaai9214

The direct effects of CO 2 level changes on plant water availability are usually ignored in plant habitat models. We compare traditional proxies for water availability with changes in soil water (fAWC) predicted by a process-based ecosystem model, which simulates changes in vegetation structure and functioning, including CO 2 physiological effects. We modelled current and future habitats of 108 European tree species using ensemble forecasting, comprising six habitat models, two model evaluation methods and two climate change scenarios. The fAWC models' projections are generally more conservative. Potential habitats shrink significantly less for boreo-alpine and alpine species. Changes in vegetation functioning and CO 2 on plant water availability should therefore be taken into account in plant habitat change projections.

Does climate determine the trophic organization of communities around the world? A recent study showed that a limited number of community trophic structures emerge when co‐occurrence of trophic guilds among large mammals is examined globally. We ask whether the pattern is general across all terrestrial mammals (n = 5272) and birds (n = 9993). We found that the six community‐trophic structures previously identified with large mammals are largely maintained when all mammals and birds are examined, both together and separately, and that bioclimatic variables, including net primary productivity (NPP), are strongly related to variation in the geographical boundaries of community trophic structures. We argue that results are consistent with the view that trophic communities are self‐organized structures optimizing energy flows, and that climate likely acts as the main control parameter by modulating the amount of solar energy available for conversion by plants and percolated through food webs across trophic communities. Gradual changes in climate parameters would thus be expected to trigger abrupt changes in energy flows resulting from phase transitions (tipping points) between different dynamical stable states. We expect future research to examine if our results are general across organisms, ecosystems, scales and methodologies, and whether inferences rooted in complex systems theory are supported. The emergence of general patterns in the functional properties of animal communities at broad scales supports the emergence of food‐web biogeography as a sub‐discipline of biogeography focused on the analysis of the geographical distributions of trophic relationships among organisms.

While the scientific community documents environmental degradation and develops scenarios to identify the operational margins of system Earth, less attention is given to how decisions are made that steer the system in one direction or the other. We propose to use strategy games for this purpose, increasing the representation of human agency in scenario development and creating spaces for deliberation between different worldviews. Played by the right people, strategy games could help break free from established norms and support more transparent democratic dialogues, responding to the human and social limitations of current decision-making. The question is, who gets to play? The empirical examples given here stem from the work of the CoForTips project (ANR‐12‐EBID‐0002) funded by the ERA-NET BiodivERsA, with the national funders ANR, BELSPO and FWF, as part of the 2012 call for research proposals, and the OPAL project financed by the Swiss National Science Foundation (r4d-Ecosystems) grant no. 152019. The MineSet model was developed by the CoForSet project, funded by the FRB 2013 call for research proposals 'Scenarios of Biodiversity for Sub-Saharan Africa', with support by the FFEM. Peer reviewed