An official website of the United States government
Poikilothermic animals comprise most species on Earth and are especially sensitive to changes in environmental temperatures. Species conservation in a changing climate relies upon predictions of species responses to future conditions, yet predicting species responses to climate change when temperatures exceed the bounds of observed data is fraught with challenges. We present a physiologically guided abundance (PGA) model that combines observations of species abundance and environmental conditions with laboratory-derived data on the physiological response of poikilotherms to temperature to predict species geographical distributions and abundance in response to climate change. The model incorporates uncertainty in laboratory-derived thermal response curves and provides estimates of thermal habitat suitability and extinction probability based on site-specific conditions. We show that temperature-driven changes in distributions, local extinction, and abundance of cold, cool, and warm-adapted species vary substantially when physiological information is incorporated. Notably, cold-adapted species were predicted by the PGA model to be extirpated in 61% of locations that they currently inhabit, while extirpation was never predicted by a correlative niche model. Failure to account for species-specific physiological constraints could lead to unrealistic predictions under a warming climate, including underestimates of local extirpation for cold-adapted species near the edges of their climate niche space and overoptimistic predictions of warm-adapted species.
more »
« less
When and how can we predict adaptive responses to climate change?
Abstract Predicting if, when, and how populations can adapt to climate change constitutes one of the greatest challenges in science today. Here, we build from contributions to the special issue on evolutionary adaptation to climate change, a survey of its authors, and recent literature to explore the limits and opportunities for predicting adaptive responses to climate change. We outline what might be predictable now, in the future, and perhaps never even with our best efforts. More accurate predictions are expected for traits characterized by a well-understood mapping between genotypes and phenotypes and traits experiencing strong, direct selection due to climate change. A meta-analysis revealed an overall moderate trait heritability and evolvability in studies performed under future climate conditions but indicated no significant change between current and future climate conditions, suggesting neither more nor less genetic variation for adapting to future climates. Predicting population persistence and evolutionary rescue remains uncertain, especially for the many species without sufficient ecological data. Still, when polled, authors contributing to this special issue were relatively optimistic about our ability to predict future evolutionary responses to climate change. Predictions will improve as we expand efforts to understand diverse organisms, their ecology, and their adaptive potential. Advancements in functional genomic resources, especially their extension to non-model species and the union of evolutionary experiments and “omics,” should also enhance predictions. Although predicting evolutionary responses to climate change remains challenging, even small advances will reduce the substantial uncertainties surrounding future evolutionary responses to climate change.
more »
« less
- Award ID(s):
- 2022036
- PAR ID:
- 10476589
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Evolution Letters
- Volume:
- 8
- Issue:
- 1
- ISSN:
- 2056-3744
- Format(s):
- Medium: X Size: p. 172-187
- Size(s):
- p. 172-187
- Sponsoring Org:
- National Science Foundation
More Like this
-
-
In many organisms, rapidly changing environmental conditions are inducing dramatic shifts in diverse phenotypic traits with consequences for fitness and population viability. However, the mechanisms that underlie these responses remain poorly understood. Endocrine signalling systems often influence suites of traits and are sensitive to changes in environmental conditions; they are thus ideal candidates for uncovering both plastic and evolved consequences of climate change. Here, we use body size and shape, a set of integrated traits predicted to shift in response to rising temperatures with effects on fitness, and insulin-like growth factor-1 as a case study to explore these ideas. We review what is known about changes in body size and shape in response to rising temperatures and then illustrate why endocrine signalling systems are likely to be critical in mediating these effects. Lastly, we discuss research approaches that will advance understanding of the processes that underlie rapid responses to climate change and the role endocrine systems will have. Knowledge of the mechanisms involved in phenotypic responses to climate change will be essential for predicting both the ecological and the long-term evolutionary consequences of a warming climate. This article is part of the theme issue ‘Endocrine responses to environmental variation: conceptual approaches and recent developments’.more » « less
-
Abstract Understanding evolutionary responses to variation in temperature and precipitation across species ranges is of fundamental interest given ongoing climate change. The importance of temperature and precipitation for multiple aspects of bumble bee (Bombus) biology, combined with large geographic ranges that expose populations to diverse environmental pressures, make these insects well‐suited for studying local adaptation. Here, we analyzed genome‐wide sequence data from two widespread bumble bees,Bombus vosnesenskiiandBombus vancouverensis, using multiple environmental association analysis methods to investigate climate adaptation across latitude and altitude. The strongest signatures of selection were observed inB. vancouverensis, but despite unique responses between species for most loci, we detected several shared responses. Genes relating to neural and neuromuscular function and ion transport were especially evident with respect to temperature variables, while genes relating to cuticle formation, tracheal and respiratory system development, and homeostasis were associated with precipitation variables. Our data thus suggest that adaptive responses for tolerating abiotic variation are likely to be complex, but that several parallels among species can emerge even for these complex traits and landscapes. Results provide the framework for future work into mechanisms of thermal and desiccation tolerance in bumble bees and a set of genomic targets that might be monitored for future conservation efforts.more » « less
-
Predicting the effects of anthropogenic climate change on Earth’s marine mollusk species is highly relevant, as many are critical human food resources and indispensable members of marine ecosystems. To predict which species will go extinct and which will survive, it is essential to understand the past climate species have experienced, as well as determine the relationship between functional traits, which provide a direct connection to organismal ecology, and survival. Many extant West Atlantic (WA) mollusks, especially gastropods and bivalves, survived the Mid-Pliocene Warm Period and the Last Interglacial, warm intervals compared to the present, that can serve as analogues for predicted future conditions of anthropogenic climate change. WA mollusks have an exceptional Neogene fossil record, which makes them an ideal group to study to develop a predictive extinction risk framework. The present research focuses on the correlation between functional traits and extinction in over 80 species of WA mollusks, both extant and extinct. Functional trait data such as body size, mobility, diet, bathymetric depth range, and organism-substrate relationship, which correlate with metabolic requirements, a known factor in extinction risk, and degree and type of ornamentation, shell shape in bivalves, and narrowness of the aperture in gastropods, which correlate with predation resistance, were collected across these species. These comprise both continuous and discrete character data. Various statistical tests were applied to the database to examine variable correlation/interaction, and the relative contributions of traits to extinction risk. Traits related to metabolism were strong predictors of survival; traits related to predation resistance play a less important role. While this study focuses on organismic traits, the aim of future research will be to explore how group characteristics such as geographic range are associated with functional traits and extinction risk for these species. A predictive framework is developed using patterns of extinction in the fossil record to infer survival of various species in the future, which will be relevant for evaluating the potential consequences of climate change, global change biology, and for determining which species should be targeted for conservation efforts.more » « less
-
Abstract As climate change advances, environmental gradients may decouple, generating novel multivariate environments that stress wild populations. A commonly invoked mechanism of evolutionary rescue is adaptive gene flow tracking climate shifts, but gene flow from populations inhabiting similar conditions on one environmental axis could cause maladaptive introgression when populations are adapted to different environmental variables that do not shift together. Genomic architecture can play an important role in determining the effectiveness and relative magnitudes of adaptive gene flow and in situ adaptation. This may have direct consequences for how species respond to climate change but is often overlooked. Here, we simulated microevolutionary responses to environmental change under scenarios defined by variation in the polygenicity, linkage, and genetic redundancy of two independent traits, one of which is adapted to a gradient that shifts under climate change. We used these simulations to examine how genomic architecture influences evolutionary outcomes under climate change. We found that climate‐tracking (up‐gradient) gene flow, though present in all scenarios, was strongly constrained under scenarios of lower linkage and higher polygenicity and redundancy, suggesting in situ adaptation as the predominant mechanism of evolutionary rescue under these conditions. We also found that high polygenicity caused increased maladaptation and demographic decline, a concerning result given that many climate‐adapted traits may be polygenic. Finally, in scenarios with high redundancy, we observed increased adaptive capacity. This finding adds to the growing recognition of the importance of redundancy in mediating in situ adaptive capacity and suggests opportunities for better understanding the climatic vulnerability of real populations.more » « less
