Climate Change Ecology最新文献

Climate change affects species and their interactions, resulting in novel communities and modified ecosystem processes. Through shifts in phenology and distribution, climatic change can disrupt interactions, including those between mutualists. Mutualisms influence the structure and stability of communities and can link species to a common fate. However, research on climate change has focused on pairwise mutualisms, neglecting the higher-order interactions that can arise when species interact with multiple mutualists. We explore the effects of climate change on tripartite interactions involving belowground mutualists, namely soil bacteria and fungi, flowering plants, and pollinators. We outline how climate change is predicted to affect the phenology and distribution of these belowground mutualists, emphasizing the consequent effects on host plant floral traits, plant-pollinator interactions, and bee behavior. We find evidence that warming, advanced snowmelt, and drought are likely to cause phenological and distributional shifts in soil microbes, leading to diminished mutualistic interactions with plants and symbiont switching. Consequently, shifts in flowering phenology, smaller floral displays, and lower quality floral rewards are expected, increasing foraging time and energy demands for bees and altering their floral preferences. Such costs could translate into reduced fitness and novel selection pressures for bees and flowering plants in the short term. We highlight knowledge gaps and ways forward, urging studies on microbe dispersal and phenological cues, experiments that manipulate soil microbe-host plant interactions under simulated climate change conditions, and large-scale field studies across environmental gradients, all with the goal of understanding how climate change will affect soil microbe-plant-pollinator mutualisms.

Climate change-induced bush encroachment into grasslands has profound impacts on herbivores in African grasslands through changing their food and water supplies and influencing their perception of predation risk, and thus modulating the trade-off between resource acquisition and predator avoidance. For plains zebras (Equus quagga), bush is usually viewed as risky because it provides cover to predators to ambush prey. Projected climate change and increase in bush coverage may elevate perceived predation risk for zebras and influence their behaviors. However, direct evidence of bush coverage impacts on herbivores’ behavioral trade-off remains scarce. We conducted field observations and counts of plains zebra behavioral investments in vigilance, grazing and other routine activities across a variety of bush densities in Kenya's Laikipia Plateau. Results suggest that increasing bush density reduces the distance at which zebras detect the approach of a potential predator. After controlling for group size, zebras are more vigilant in dense versus open habitats. Increase in bush coverage has little impact on grazing time allocation, however it does reduce bite rate. Zebras spend less time on activities other than vigilance or grazing in bushier habitats. Our finding implies that increases in bush encroachment will increase the perception of predation risk by zebras, and reduce efficiency on food uptake and other essential behaviors. Maintaining sufficient area of open grasslands, in part by protecting elephants as ecological engineers, will help sustain populations of zebras and other large herbivores wherever climate change and land use change increases bush density.

Climate change impacts animal abundances, distributions, and behaviors, frequently at the detriment to individuals. However, for many animals, including butterflies, current research focuses primarily on estimating abundance and distribution without observing behavior. Because behaviors often respond to climate change before other metrics, understanding behavioral change is critical for future climate change research and projections. Therefore, we investigated weather related changes in adult butterfly behavior using snapshot behavioral observations taken as part of a four year study of butterfly abundance throughout North Dakota, USA. Across 1,107 site-visits, we categorized adult butterfly behavior using 146,610 observations while also recording local weather variables with each site visit. We found patterns in butterfly behavior within years, including more flying and less resting at sites that were warmer during that site visit. We also observed differences across years, including more flying overall and a weaker behavioral response to temperature in a year that was particularly cool and wet. Further incorporating such behavioral observations into abundance surveys can help lead to better insights about weather-related variation in behavioral patterns and their consequences for animals facing climate change.

COVID-19 pandemic has been a subject of extensive study. However, it is still unclear why it was restricted to higher latitudes during the initial days and later cascaded in the tropics. Here, we analyzed 176 SARS-CoV-2 genomes across different climate zones and Köppen's climate that provided insights about within-species virus evolution and its relation to abiotic factors. Two genetically variant groups, named G1 and G2, were identified, well defined by four mutations. The G1 group (ancestor) is mainly restricted to warm and moist, temperate climate (Köppen's C climate) while its descendent G2 group surpasses the climatic restrictions of G1, initially cascading into neighboring cold climate (D) of higher latitudes and later into the hot climate of the tropics (A). It appears that the gradation of temperate climate (Cfa-Cfb) to cold climate (Dfa-Dfb) drives the evolution of G1 into the G2 variant group, which later adapted to tropical climate (A) as well. It seems this virus followed an inverse latitudinal gradient in the beginning due to its preference towards temperate (C) and cold climate (D). Our work elucidates virus evolutionary studies combined with climatic studies can provide crucial information about the pathogenesis and natural spreading pathways in such outbreaks, which is hard to achieve through individual studies. Mutational insights gained may help design an efficacious vaccine.

Plastic changes in behavior can allow animals to adapt to changes in their environment, but the adaptive role of rapid behavioral adjustments for surviving anthropogenically-induced environmental change is less well understood, especially with regard to behavioral plasticity facilitating the evolution of other traits. Here we examine the ability of lizards to rapidly acquire adaptive antipredator behavior following a single predator exposure. Fence lizards typically rely on crypsis to avoid predator detection, but this is maladaptive in the face of invasive venomous fire ants that can successfully locate and attack immobile lizards. Fire ant-naïve juvenile lizards shifted their behavior to flee from fire ant attack after a single encounter with these predatory ants. Our results provide evidence of rapid phenotypic accommodation to an environmental threat that likely played a role in population persistence after fire ant invasion and subsequent evolution of multiple traits.

Accurate predictions of the effects of warming temperatures under climate change on an individual species require an accurate characterization of its current and future thermal environment. Behavioral responses to environmental heterogeneity are an important but poorly understood determinant of species’ body temperatures and thermal risks. In this paper we describe the steps necessary for determining a species’ opportunities for behavioral buffering of climate change, and provide examples using a combination of previously published studies and new results for the intertidal snail Nucella ostrina. We find that N. ostrina’s current patterns of daily microhabitat selection have the potential to buffer it from warming temperatures under climate change. N. ostrina’s foraging behavior is highly correlated with the 14.5 d semilunar tidal cycle, shielding it from both current and future thermal stress.

The acute stress response is a cornerstone of animal behavior research, but little is currently understood about how responses to acute stressors (i.e. discrete noxious stimuli) may be altered in future climates. As climate change ensues, animals may experience chronic stress due to persistent warmer temperatures and environmental conditions altered by weather extremes, such as wildfires and storms, which are expected to increase in frequency and intensity. This chronic stress has the potential to cause changes in animal responses to acute stress, but whether such changes occur is unclear. Here, we investigated whether new environmental conditions caused by wildfire affected the fight-or-flight component of the acute stress response of a widespread social insect. We compared thatch ant (Formica obscuripes) behavior in neighboring sagebrush steppe areas that were unburned or burned three months prior. As predicted, we found that ant workers primarily defended their colonies by attacking a threatening stimulus, but ants in the burned environment were more likely to flee from the stimulus. While causal mechanisms require further study, these findings suggest that ant workers provide less protection for their colonies following wildfire, which may increase individual worker survival but make colonies more vulnerable to antagonists. As chronic stress due to wildfires and other shifting climatic variables becomes more widespread, understanding changes in animal responses to acute stressors will be crucial for anticipating animal survival in the Anthropocene. We suggest several research priorities for work on stress-related animal behaviors in environments altered by climate change, including greater focus on invertebrates.