DSpace Angular :: Browsing by Author "Rezende, Enrico L."

Browsing by Author "Rezende, Enrico L."

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Biological trade-offs underpin coral reef ecosystem functioning
(2022) Schiettekatte, Nina M. D.; Brandl, Simon J.; Casey, Jordan M.; Graham, Nicholas A. J.; Barneche, Diego R.; Burkepile, Deron E.; Allgeier, Jacob E.; Arias-Gonzalez, Jesus E.; Edgar, Graham J.; Ferreira, Carlos E. L.; Floeter, Sergio R.; Friedlander, Alan M.; Green, Alison L.; Kulbicki, Michel; Letourneur, Yves; Luiz, Osmar J.; Merciere, Alexandre; Morat, Fabien; Munsterman, Katrina S.; Rezende, Enrico L.; Rodriguez-Zaragoza, Fabian A.; Stuart-Smith, Rick D.; Vigliola, Laurent; Villeger, Sebastien; Parravicini, Valeriano
Integrating bioenergetic models and global coral reef fish community surveys, the authors show that there are functional trade-offs, meaning that no community can maximize all functions, and that dominant species underpin local functions, but their identity varies geographically.
Body size variation in polyplacophoran molluscs: Geographical clines and community structure along the south‐eastern Pacific
(2021) Ibáñez, Christian M. ; Carter, Mauricio J. ; Aguilera, Moisés A. ; Pardo‐Gandarillas, M. Cecilia ; Rezende, Enrico L. ; Tomasovych, Adam
Aim To evaluate the latitudinal pattern of body size within and among chiton species employing phylogenetically structured analyses and examine the role ofgeographical variation in temperature, productivity and oxygen availability as potential environmental drivers. Location Coastal habitats of the south-eastern Pacific along a latitudinal range of nearly 6,000 km, from the equator to Patagonia (c. 2 degrees to 56 degrees S). Time period Present (2011-2017). Major taxa studied Thirty-one species of polyplacophoran molluscs. Methods We measured the body length of 6,162 individuals collected in 62 sites, and reconstructed the phylogeny of this group based on two mitochondrial and one nuclear gene regions. We combined this information with data of sea surface temperature, chlorophyll-a concentration-as a proxy of primary productivity-and dissolved oxygen, and assessed which variables best explain the variation in size both within and among species employing phylogenetic generalized least squares (PGLS) and a model comparison approach. Main conclusions Our analyses show that body size increases consistently with latitude, both within and among species, following Bergmann's rule. Variation in sea surface temperature along the latitudinal gradient provided a substantially better fit than chlorophyll-a and dissolved oxygen. Our results support the temperature-size rule for this lineage and suggest that similar processes could underlie the emergence of intra- and interspecific gradients in body size of polyplacophorans. At the community level, chiton species richness was higher at intermediate latitudes and positively correlated with body size variation, suggesting that heterogeneity in size may reduce interspecific competition and contribute to species coexistence in this group. Overall, our study demonstrates that historical events, macroecological adaptive trends and local processes at the community level contribute to the distribution and size variation of polyplacophoran species throughout the south-eastern Pacific.
Climate change and population persistence in a hibernating marsupial
(2024) Nespolo, Roberto F.; Quintero-Galvis, Julian F.; Fonturbel, Francisco E.; Cubillos, Francisco A.; Vianna, Juliana; Moreno-Meynard, Paulo; Rezende, Enrico L.; Bozinovic, Francisco
Climate change has physiological consequences on organisms, ecosystems and human societies, surpassing the pace of organismal adaptation. Hibernating mammals are particularly vulnerable as winter survival is determined by short-term physiological changes triggered by temperature. In these animals, winter temperatures cannot surpass a certain threshold, above which hibernators arouse from torpor, increasing several fold their energy needs when food is unavailable. Here, we parameterized a numerical model predicting energy consumption in heterothermic species and modelled winter survival at different climate change scenarios. As a model species, we used the arboreal marsupial monito del monte (genus Dromiciops), which is recognized as one of the few South American hibernators. We modelled four climate change scenarios (from optimistic to pessimistic) based on IPCC projections, predicting that northern and coastal populations (Dromiciops bozinovici) will decline because the minimum number of cold days needed to survive the winter will not be attained. These populations are also the most affected by habitat fragmentation and changes in land use. Conversely, Andean and other highland populations, in cooler environments, are predicted to persist and thrive. Given the widespread presence of hibernating mammals around the world, models based on simple physiological parameters, such as this one, are becoming essential for predicting species responses to warming in the short term.
Heat tolerance of marine ectotherms in a warming Antarctica
(2023) Molina, Andres N.; Pulgar, Jose M.; Rezende, Enrico L.; Carter, Mauricio J.
Global warming is affecting the Antarctic continent in complex ways. Because Antarctic organisms are specialized to living in the cold, they are vulnerable to increasing temperatures, although quantitative analyses of this issue are currently lacking. Here we compiled a total of 184 estimates of heat tolerance belonging to 39 marine species and quantified how survival is affected concomitantly by the intensity and duration of thermal stress. Species exhibit thermal limits displaced toward colder temperatures, with contrasting strategies between arthropods and fish that exhibit low tolerance to acute heat challenges, and brachiopods, echinoderms, and molluscs that tend to be more sensitive to chronic exposure. These differences might be associated with mobility. A dynamic mortality model suggests that Antarctic organisms already encounter temperatures that might be physiologically stressful and indicate that these ecological communities are indeed vulnerable to ongoing rising temperatures.
Individual variation in heat tolerance and metabolism in marine Antarctic organisms
(2024) Varas, Oscar; Molina, Andres N.; Garcia-Huidobro, M. Roberto; Aldana, Marcela; Rezende, Enrico L.; Carter, Mauricio J.; Galban-Malagon, Cristobal; Pulgar, Jose M.
Climate change is one of the main concerns to Antarctic biodiversity. Since temperature plays a crucial role in various biological traits, it is key to understand how warming may affect organisms specialized to live in the cold habitats. Although heat tolerance of several polar species is known, little emphasis has been given to individual variation and its relationship with other biological traits such as metabolic performance. In this study, we investigated the association between thermal sensitivity in metabolism (Q10) and heat tolerance (z) in six Antarctic marine organisms, including two fish species (Harpagifer antarcticus and Notothenia coriiceps), three crustaceans (Bovallia gigantea, Glyptonotus antarcticus, and Paraceradocus miersi), and one mollusk (Trophon nucelliformis). For this, we measured routine metabolic rates (RMR, mg O2/h) followed by heat tolerance measurements to reconstruct dose-response curves employing sublethal assays or thermal-collapse time (TCT) curves. Analyses reveal a negative relationship between the intercept and the slope of the temperature tolerance curves (CTmax and z values, respectively) against Q10, but only when T. nucelliformis was included in the generalized linear model. Therefore Q10 may be a good predictor of heat tolerance, but it is not true for chordate or arthropod species studied. Additionally, CTmax and z values exhibited a positive relationship consistent with previous studies. This study represents the first example of temperature tolerance curves quantified on an individual basis, and the analyses provide some evidence that thermal sensitivity in metabolism and heat tolerance are correlated. In future studies, it will be crucial to determine whether this relationship is robust and how it may impact the response of different lineages to accelerated warming.
Intra and interspecific variation in thermal performance and critical limits in anurans from southern Chile
(2024) Vidal, Marcela A.; Rezende, Enrico L.; Bacigalupe, Leonardo D.
The relationship between temperature and performance can be illustrated through a thermal performance curve (TPC), which has proven useful in describing various aspects of ectotherms' thermal ecology and evolution. The parameters of the TPC can vary geographically due to large-scale variations in environmental conditions. However, only some studies have attempted to quantify how thermal performance varies over relatively small spatial scales, even in the same location or consistently among individuals within a species. Here, we quantified individual and species variation in thermal sensitivity of locomotor performance in five amphibia Eupsophus species found in the temperate rainforests of southern Chile and compared their estimates against co-occurring species that exhibit a substantially more extensive distributional range. We measured critical thermal limits and jumping performance under five different temperatures. Our results suggest that thermal responses are relatively conserved along the phylogeny, as the locomotor performance and thermal windows for activity remained narrow in Eupsophus species when compared against results observed for Batrachyla taeniata and Rhinella spinulosa. Additionally, we found significant individual differences in locomotor performance within most species, with individual consistency in performance observed across varied temperatures. Further analyses explored the influence of body size on locomotor performance and critical thermal limits within and between species. Our results suggest a trade-off scenario between thermal tolerance breadth and locomotor performance, where species exhibiting broader thermal ranges might have compromised performance. Interestingly, these traits seem partly mediated by body size variations, raising questions about potential ecological implications.
Long-term forecast of thermal mortality with climate warming in riverine amphipods
(2023) Verberk, Wilco C. E. P.; Hoefnagel, K. Natan; Peralta-Maraver, Ignacio; Floury, Mathieu; Rezende, Enrico L.
Forecasting long-term consequences of global warming requires knowledge on thermal mortality and how heat stress interacts with other environmental stressors on different timescales. Here, we describe a flexible analytical framework to forecast mortality risks by combining laboratory measurements on tolerance and field temperature records. Our framework incorporates physiological acclimation effects, temporal scale differences and the ecological reality of fluctuations in temperature, and other factors such as oxygen. As a proof of concept, we investigated the heat tolerance of amphipods Dikerogammarus villosus and Echinogammarus trichiatus in the river Waal, the Netherlands. These organisms were acclimated to different temperatures and oxygen levels. By integrating experimental data with high-resolution field data, we derived the daily heat mortality probabilities for each species under different oxygen levels, considering current temperatures as well as 1 and 2? warming scenarios. By expressing heat stress as a mortality probability rather than a upper critical temperature, these can be used to calculate cumulative annual mortality, allowing the scaling up from individuals to populations. Our findings indicate a substantial increase in annual mortality over the coming decades, driven by projected increases in summer temperatures. Thermal acclimation and adequate oxygenation improved heat tolerance and their effects were magnified on longer timescales. Consequently, acclimation effects appear to be more effective than previously recognized and crucial for persistence under current temperatures. However, even in the best-case scenario, mortality of D. villosus is expected to approach 100% by 2100, while E. trichiatus appears to be less vulnerable with mortality increasing to 60%. Similarly, mortality risks vary spatially: In southern, warmer rivers, riverine animals will need to shift from the main channel toward the cooler head waters to avoid thermal mortality. Overall, this framework generates high-resolution forecasts on how rising temperatures, in combination with other environmental stressors such as hypoxia, impact ecological communities.
Phenotypic specialization of the pea aphid in its southern limit of distribution
(2023) Martel, Sebastian I.; Zamora, Cristian A.; Behrens, Camilo A.; Rezende, Enrico L.; Bozinovic, Francisco
The success of biological invasions ultimately relies on phenotypic traits of the invasive species. Aphids, which include many important pests worldwide, may have been successful invading new environments partly because they can maximize reproductive output by becoming parthenogenetic and losing the sexual phase of their reproductive cycle. However, invasive populations of aphids invading wide ranges can face contrasting environmental conditions and requiring different phenotypic strategies. Besides transitions in their reproductive cycle, it is only partially known which phenotypic traits might be associated to the invasion success of aphid populations in extended novel ranges. Here, we used four genotypes of the pea aphid Acyrthosiphon pisum from two localities in Chile to test for phenotypic specialization that might explain their establishment and spread in habitats exhibiting contrasting environmental conditions. We show that lineages living at a higher latitude with low temperatures show, in addition to facultative sexual reproduction, smaller body sizes, lower metabolic rates and a higher tolerance to the cold than the obligate asexual lineages living in a mild weather, at the expense of fecundity. Conversely, at higher temperatures only asexual lineages were found, which exhibit larger body sizes, higher reproductive outputs and consequently enhanced demographic ability. As a result, in conjunction with the reproductive mode, lineage specialization in physiological and life-history traits could be taken into account as an important strategy for populations of pea aphid to effectively invade extended novel ranges comprising different climatic conditions.
Plasticity cannot fully compensate evolutionary differences in heat tolerance across fish species
(2024) Molina, Andres N.; Carter, Mauricio J.; Rezende, Enrico L.
Understanding how evolution and phenotypic plasticity contribute to variation in heat tolerance is crucial to predicting responses to warming. Here, we analyze 272 thermal death time curves of 53 fish species acclimated to different temperatures and quantify their relative contributions. Analyses show that evolution and plasticity account, respectively, for 80.5% and 12.4% of the variation in elevation across curves, whereas their slope remained invariant. Evolutionary and plastic adaptive responses differ in magnitude, with heat tolerance increasing to 0.54 degrees C between species and 0.32 degrees C within species for every 1 degrees C increase in environmental temperatures. After successfully predicting critical temperatures under ramping conditions to validate these estimates, we show that fish populations can only partly ameliorate the impact of warming waters via thermal acclimation, and this deficit in plasticity could increase as the warming accelerates.
Rapid turnover of a pea aphid superclone mediated by thermal endurance in central Chile
(2024) Martel, Sebastian I.; Zamora, Cristian A.; Ricote, Natalia; Sepulveda, Daniela A.; Maheo, Frederique; Simon, Jean-Christophe; Figueroa, Christian C.; Rezende, Enrico L.; Bozinovic, Francisco
Global change drivers are imposing novel conditions on Earth's ecosystems at an unprecedented rate. Among them, biological invasions and climate change are of critical concern. It is generally thought that strictly asexual populations will be more susceptible to rapid environmental alterations due to their lack of genetic variability and, thus, of adaptive responses. In this study, we evaluated the persistence of a widely distributed asexual lineage of the alfalfa race of the pea aphid, Acyrthosiphon pisum, along a latitudinal transect of approximately 600 km in central Chile after facing environmental change for a decade. Based on microsatellite markers, we found an almost total replacement of the original aphid superclone by a new variant. Considering the unprecedented warming that this region has experienced in recent years, we experimentally evaluated the reproductive performance of these two A. pisum lineages at different thermal regimes. The new variant exhibits higher rates of population increase at warmer temperatures, and computer simulations employing a representative temperature dataset suggest that it might competitively displace the original superclone. These results support the idea of a superclone turnover mediated by differential reproductive performance under changing temperatures.
Temperature adaptation and its impact on the shape of performance curves in Drosophila populations
(2023) Alruiz, Jose M.; Peralta-Maraver, Ignacio; Bozinovic, Francisco; Santos, Mauro; Rezende, Enrico L.
Understanding how species adapt to different temperatures is crucial to predict their response to global warming, and thermal performance curves (TPCs) have been employed recurrently to study this topic. Nevertheless, fundamental questions regarding how thermodynamic constraints and evolution interact to shape TPCs in lineages inhabiting different environments remain unanswered. Here, we study Drosophila simulans along a latitudinal gradient spanning 3000 km to test opposing hypotheses based on thermodynamic constrains (hotter-is-better) versus biochemical adaptation (jack-of-all-temperatures) as primary determinants of TPCs variation across populations. We compare thermal responses in metabolic rate and the egg-to-adult survival as descriptors of organismal performance and fitness, respectively, and show that different descriptors of TPCs vary in tandem with mean environmental temperatures, providing strong support to hotter-is-better. Thermodynamic constraints also resulted in a strong negative association between maximum performance and thermal breadth. Lastly, we show that descriptors of TPCs for metabolism and egg-to-adult survival are highly correlated, providing evidence of co-adaptation, and that curves for egg-to-adult survival are systematically narrower and displaced toward lower temperatures. Taken together, our results support the pervasive role of thermodynamics constraining thermal responses in Drosophila populations along a latitudinal gradient, that are only partly compensated by evolutionary adaptation.
Temperature variability and metabolic adaptation in terrestrial and aquatic ectotherms
(2023) Carter, Mauricio J.; Cortes, Pablo A.; Rezende, Enrico L.
Thermodynamics is a major factor determining rates of energy expenditure, rates of biochemical dynamics, and ultimately the biological and ecological processes linked with resilience to global warming in ectothermic organisms. Nonetheless, whether ectothermic organisms exhibit general adaptive metabolic responses to cope with worldwide variation in thermal conditions has remained as an open question. Here we combine a model comparison approach with a global dataset of standard metabolic rates (SMR), including 1,160 measurements across 788 species of aquatic invertebrates, insects, fishes, amphibians and reptiles, to investigate the association between metabolic rates and environmental temperatures in their respective habitats. Our analyses suggest that variation in SMR after removing allometric and thermodynamic effects is best explained by the temperature range encountered across seasons, which always provided a better fit than the average temperature for the hottest and coldest month and mean annual temperatures. This pattern was consistent across taxonomic groups and robust to sensitivity analyses. Nonetheless, aquatic and terrestrial lineages responded differently to seasonality, with SMR declining - 6.8% degrees C- 1 of thermal range across seasons in aquatic organisms and increasing 2.8% degrees C- 1 in terrestrial organisms. These responses may reflect alternative strategies to mitigate the impact of increments in warmer temperatures on energy expenditure, either by means of metabolic reduction in thermally homogeneous water bodies or effective behavioral thermoregulation to exploit temperature heterogeneity on land.
Temperature variability and thermal performance in ectotherms: acclimation, behaviour, and experimental considerations
(2016) Bozinovic, Francisco; Sabat, Pablo; Rezende, Enrico L.; Canals, Mauricio
Background: Among the predictions of the effect of future climate change, the impact of thermal conditions at local levels on the performance of individuals and their acclimation capacities is key to understanding animals' responses to global warming. Woodlice (the terrestrial isopod Porcellio laevis) exhibit a readily observed behaviour that may reflect their acclimation capacities. When they find themselves on their back, they sometimes roll over (i.e. right themselves). Whether they do, and how fast they do it, are measures of their behaviour and performance that vary with ambient temperature.
Thermodynamic effects drive countergradient responses in the thermal performance of Littorina saxatilis across latitude
(2023) Dwane, Christopher; Rezende, Enrico L.; Tills, Oliver; Galindo, Juan; Rolan-Alvarez, Emilio; Rundle, Simon; Truebano, Manuela
Thermal performance curves (TPCs) provide a powerful framework to assess the evolution of thermal sensitivity in populations exposed to divergent selection regimes across latitude. However, there is a lack of consensus regarding the extent to which physiological adjustments that compensate for latitudinal temperature variation (metabolic cold adaptation; MCA) may alter the shape of TPCs, including potential repercussion on upper thermal limits. To address this, we compared TPCs for cardiac activity in latitudinally-separated populations of the intertidal periwinkle Littorina saxatilis. We applied a non-linear TPC modelling approach to explore how different metrics governing the shape of TPCs varied systematically in response to local adaptation and thermal acclimation. Both critical upper limits, and the temperatures at which cardiac performance was maximised, were higher in the northernmost (cold-adapted) pop-ulation and displayed a countergradient latitudinal trend which was most pronounced following acclimation to low temperatures. We interpret this response as a knock-on consequence of increased standard metabolic rate in high lat-itude populations, indicating that physiological compensation associated with MCA may indirectly influence variation in upper thermal limits across latitude. Our study highlights the danger of assuming that variation in any one aspect of the TPC is adaptive without appropriate mechanistic and ecological context.
Upper thermal limits and risk of mortality of coastal Antarctic ectotherms
(2023) Carter, Mauricio J.; Garcia-Huidobro, M. Roberto; Aldana, Marcela; Rezende, Enrico L.; Bozinovic, Francisco; Galban-Malagon, Cristobal; Pulgar, Jose M.
Antarctic marine animals face one of the most extreme thermal environments, characterized by a stable and narrow range of low seawater temperatures. At the same time, the Antarctic marine ecosystems are threatened by accelerated global warming. Determining the upper thermal limits (CTmax) is crucial to project the persistence and distribution areas of the Antarctic marine species. Using thermal death time curves (TDT), we estimated CTmax at different temporal scales from 1 minute to daily and seasonal, the predict vulnerability to the current thermal variation and two potential heatwave scenarios. Our results revealed that CTmax at 1 min are far from the temperature present in the marine intertidal area where our study species, showing Echinoderm species higher CTmax than the Chordata and Arthropods species. Simulations indicated that seasonal thermal variation from the intertidal zone contributed to basal mortality, which increased after considering moderate scenarios of heatwaves (+2 degrees C) in the Shetland Archipelago intertidal zone. Our finding highlighted the relevance of including exposure time explicitly on the CTmax estimates, which deliver closer and more realistic parameters according to the species that may be experiencing in the field.

Browsing by Author "Rezende, Enrico L."

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