**Author(s):** Snyder, K; Sellers, M; Creanza, N Introduction<br><br>
Environmental stress, especially during development, can cause impaired learning in individuals. Thus, learned behaviors, such as birdsong, may exhibit unique evolutionary dynamics after severe weather events relative to other traits. We predict that ecosystem-level stressors may cause population-level changes to birdsong as cohorts experience early-life stress, learn songs imperfectly, and tutor future generations. <br>
Approach
In 2016, an unprecedented drought affected western New York. We analyzed publicly available and our own birdsong recordings from 2010-2020, comparing two species in the drought-affected area and a nearby unaffected area. We also developed an agent-based model of song evolution after environmental stress.<br>
Results and Conclusions
We found drought-associated song changes in the species with more complex songs but not in the species with a simple song, implying that stress-induced deficits may disproportionately affect traits that are more difficult to learn. With our model, we found important factors for enduring cultural evolution after stress: population isolation and stressor duration. Together, these results demonstrate that climatic events can induce population-level trait evolution due to disruption in learning.

Cultural evolution after environmental stress: a case study of songbird populations affected by the 2016 New York drought

Critical thinking is an important skill for students, particularly in the climate change debate. Students need to be able to distinguish between facts and misinformation. In order to access students’ critical thinking skills semi-structured interviews were conducted with eight students aiming to become future physics teachers as well as with five students from Saxonian high schools. The interviews were based on five competences of critical thinking defined by Halpern (verbal reasoning, argument analysis, hypothesis testing, likelihood and uncertainty, problem solving and decision making) as well as content knowledge about climate change (such as greenhouse effect, carbon cycle, etc.). All interviews were recorded, transcribed and analyzed using the qualitative content analysis by Kuckartz. The results from the interviews form the base for the development of the test on critical thinking on climate change, as well as teaching materials to enhance critical thinking skills. The results from the interviews will be presented.

Students' critical thinking skills in relation to climate change

In California and other western states, discussions about climate change and water access have become increasingly urgent. Connecting science learning inside the classroom to real issues that affect our students and their families is key to help students see science as a tool to work for change in their communities. Place-based education, which is rooted in historic and Indigenous educational practices, strongly supports these goals. In our Physical Science course for ninth and tenth graders, we added an outdoor experiential component to our “Science of Water” unit thereby placing our learning about water into our local context of rural Northern California. From the chemical properties of water, power generation via our local hydroelectric dam, decisions about water usage and the effects on ecosystems, and the implications of climate change, students can see the connections between all of these topics rather than learning each in isolation in separate courses.

Place-based education in high school physical science

Lighter-than-air ballooning ranges from flame-carrying “sky lanterns” (not a recommended activity) that have been flown for centuries, to the earliest balloon flights carrying people in 1783, to the largest flying vehicles – the amazing airships from the decades before WWII, to rubber and mylar “party” balloons, to tourist-carrying hot-air balloons, to home-built solar balloons, to pico-balloons capable of circumnavigating the earth (multiple times!), to latex-rubber weather balloons, zero-pressure balloons, and super-pressure balloons capable of carrying curricular and research payloads into the stratosphere. Lighter-than-air ballooning provides a context for students of all ages to study aviation history and to do many engaging STEM lessons ranging from studying buoyancy and the properties of lifting gases, to measuring the extreme conditions of the atmosphere and studying weather/climate, to predicting balloon trajectories and tracking flights, to building and operating “near-space” vehicles, to doing photography and remote sensing, to programming microcontrollers and analyzing sensor data.

Overview of Educational Applications of Lighter-Than-Air Ballooning

Galactic cosmic rays are high-energy particles that impinge on Earth’s atmosphere, in the form of positively charged particles, protons. The protons interact with atmospheric nuclei to produce a cascade of secondary particles known as a galactic cosmic ray shower. This post-collision secondary shower depends on altitude, latitude, solar activity, and air pressure. The Regener-Pfotzer (R-P) maximum, which is stated to be between 15-25 km, is the altitude where the maximum number of charged particle detections is measured with a Geiger-Müller detector. In order to better understand the dynamics of the collisions, a flight stack containing two payloads was flown. One payload contained four pancake shaped Geiger counters measuring vertical and horizontal charged particle coincidences. The other payload measured the omnidirectional charge particle interactions. Data show that a R-P maximum occurs at different altitudes depending on direction of the coincidences consistent with previous research in this area.

High Altitude Balloon Directional Measurements of Cosmic Ray Shower Events

Although there is much controversy regarding the effects of ocean acidification on the behaviour of marine fish, marine invertebrates have been much less studied. Dungeness crabs, Metacarcinus magister, are found on the West coast of North American and their commercial and recreational fishery is one of the most valuable fishery in the Pacific region, with annual revenues of $220 million. Dungeness crabs live in the deep-sea and enter intertidal areas in order to find food. Previous studies have found that they routinely encounter pCO2 concentrations of up to 1300 µatm in their coastal habitat and that these levels of ocean acidification can affect larval development and mechanoreceptors. We exposed adult Dungeness crabs to control (600 µatm) and high pCO2 (1300 µatm) for 10 days and assessed their behaviour and physiology using electrophysiology, gene expression, immunohistochemistry and transmission electron microscopy of their olfactory organs, the antennules. Dungeness crabs exposed to high pCO2 had a 25% lower rate of antennular flicking rate in response to all concentrations of cadaverine, a food cue, than crabs exposed to control pCO2. No differences in antennular flicking were found in response to ammonium chloride, a deterant, however there was a large increase in the expression of Rh proteins that function as ammonia transporters in their antennules indicating a potential compensatory mechanism. We propose that a more holistic approach to the overall question of the effects of ocean acidification needs to be taken at multiple levels of biological organization and using environmentally relevant odorants and concentrations.

The effects of simulated ocean acidification on the behaviour and physiology of the economically important Dungeness crab, Metacarcinus magister

Ectothermic animals represent most of the animal diversity on the planet and yet, are the most challenged by rising temperatures. As such, understanding the factors affecting thermal tolerance is crucial for predicting the impact climate change will have on ectotherms. However, the role developmental plasticity plays in allowing populations to cope with thermal extremes is poorly understood. Neglecting how early environmental experiences shape thermal tolerance (i.e., developmental plasticity) may be an important oversight given that early life experiences have major and often persistent effects on phenotypes. To quantify the acute and persistent influence of early thermal environments on thermal tolerance, we systematically reviewed 6000 studies and meta-analysed data from 150 studies. In this talk, I will address the following questions: How much do early thermal environments impact heat tolerance, and is that enough to compensate for rising temperatures? Are embryos more plastic than juveniles? Do early thermal environments have persistent influence on heat tolerance? What is the current state of knowledge and what are pressing future directions in the field?

Developmental plasticity in thermal tolerance: ontogenetic variation, persistence, and future directions

Phenotypic plasticity can increase resilience of animals to environmental change, and can therefore be important in naturally variable environments and under anthropogenic climate change. Phenotypic plasticity presents at three time scales, within-individual acclimation, developmental plasticity, and transgenerational effects. These different forms of plasticity can adjust phenotypes to at least partially buffer the organism from potentially harmful environmental conditions. Plasticity can thereby be important for population persistence and species survival. Conservation is commonly applied in a species-specific ecological context. However, it may be that populations within species have different capacities for plasticity, which may render the species as a whole more resilient to change via the portfolio effect. We tested this hypothesis by implementing novel meta-analytic approaches to quantify plastic capacities across populations of ectothermic species. We determined whether moderators including ecosystem (aquatic and terrestrial), plastic mechanisms (acclimation, developmental and transgenerational) and environmental variables (temperature and salinity) impact variability in plasticity between populations. The outcome of this study are important for conservation and in an evolutionary context to understand the complexity of transient responses to environmental change within species.

Are there differences in plasticity between populations within species?

Anthropogenic increases in atmospheric CO2 levels are raising seawater temperatures, lowering seawater oxygen concentrations and pH (‘climate-related stressors’, CRS), among other changes. Under such change, some marine groups, such as stony corals, may have less ability to tolerate stress than others, potentially leading to population loss and thereby extinction. However, whether these vulnerabilities directly scale up to extinction risk, or tend to be somehow compensated e.g. by rapid range shifts, is unclear because few modern, global extinctions are unequivocally caused by CRS. We use meta-analysis to attempt a quantitative cross-scale evaluation of the role of CRS as extinction triggers. We do this by comparing individual responses to CRS in laboratory experiments and the range shift responses to global warming over recent decades, to extinction selectivity at ancient hyperthermal events and across the sum of metazoan evolutionary history, the Phanerozoic aeon. Clades and traits with strong negative responses to experimental CRS are most likely to go extinct at hyperthermal events, their genera also having the shortest geological durations. Among CRS, the synergistic combination of seawater warming and hypoxia has the most severe impact on marine organism performance. Response details suggest chiefly metabolic constraints in setting organism performance responses to CRS, which appear to scale up to extinction probabilities of past (and potentially future?) hyperthermal events. Ecological experiments are the only way to test underlying physiological mechanisms. Meanwhile, the fossil record documents myriad extinctions, often with strong selectivity patterns, that amount to mass proportions under hyperthermal conditions. Uniting the strengths of the two approaches may enrich our abilities to predict the future.

A dangerous synergy of warming and hypoxia: the past and present for the future

Giant clams are threatened by overexploitation for human consumption, their valuable shells and the aquarium trade. Consequently, these iconic megafauna are extinct in some former areas of their range and included in the IUCN Red List of Threatened Species and CITES list. Now, giant clams are also threatened by rapid environmental change from both a suite of local- to regional-scale stressors, such poor water quality and pollution, and global change stressors, including ocean heating and acidification. The interplay between local- to regional-scale and global-scale drivers is likely to cause an array of lethal and sub-lethal effects, potentially limiting giant clam depth distribution on coral reefs and decreasing suitable habitat area within natural ranges. International efforts urgently need to reduce CO2 emissions to avoid lethal and sub-lethal effects on giant clams. Meanwhile, knowledge of ecological and physiological responses to local–regional and global stressors could play a critical role in the conservation of these species through rapid environmental change. Further work on how biological responses translate into habitat requirements as global change progresses, selective breeding for resilience, the capacity for rapid adaptive responses of the giant clam holobiont, and valuing tourism potential may help improve the prospects of these charismatic megafauna over coming decades.

Conserving threatened coastal wildlife during rapid environmental change: using biological responses to inform management strategies of giant clams

The ability of populations to expand their geographic ranges, whether as invaders or climate migrants, presents among the most serious global problems today. However, fundamental mechanisms that enable certain populations to rapidly adapt to novel habitats remain poorly understood. In recent years, populations of the copepod Eurytemora affinis species complex have invaded freshwater habitats multiple times independently from saline sources. These copepods are dominant grazers in aquatic habitats throughout the Northern Hemisphere and support major fisheries. Intriguingly, evolutionary changes during these salinity transitions often involved the same loci, with selection often acting on the same SNPs (alleles), in wild populations and laboratory selection lines. In our laboratory natural selection experiment, the same SNPs were favored across replicate selection lines far beyond expectations. In both wild populations and laboratory selection lines, ion transporter genes appeared as the dominant functional category under selection. Using extensive simulations, we found that this degree of parallelism was consistent with synergistic epistasis among alleles responding in concert across replicate selection lines for this polygenic trait (salinity tolerance). The effect of synergistic epistasis appeared greater than selection from balanced polymorphisms in promoting parallel evolution. Our results were consistent with mechanisms of ion uptake from dilute habitats, requiring the coordinated action of cooperating ion transporter proteins. Most notably, our results suggest that a very specific set of ion transporter alleles might be necessary for freshwater adaptation to occur in this system, pointing to a canalized evolutionary pathway. Thus, we find strong support for a novel and potentially widespread mechanism, namely positive epistasis, in promoting this parallel and canalized response. This research is funded by NSF-OCE, NSF-DEB, and ANR (Macron’s Make Our Planet Great Again award).

Mechanisms of parallel adaptation in a widespread copepod

Climate change is increasing both the average ambient temperature and the frequency and severity of heat waves. While direct mortality induced by heat waves is increasingly reported, sub-lethal effects are also likely to impact population dynamics and persistence. We hypothesized that accelerated cellular ageing could be a cost of being exposed to higher ambient temperature. We tested this hypothesis in two common European passerine species by experimentally increasing nest box temperature by ca. 2°C during postnatal growth and measuring telomere length as a biomarker of ageing. In great tits, we also estimated the impact on medium-term survival and measured a large set of physiological markers including thyroid hormones, glucocorticoid signaling, oxidative stress, mitochondrial density and telomere maintenance mechanisms. We show that in both species, increasing early-life temperature does not affect growth or survival to fledging, but leads to an acceleration in the shortening of telomeres. In great tits, such shortening of telomeres was not explained by increased oxidative stress levels, but more likely by an increase in energy demand (i.e. higher thyroid hormones levels, increased expression of glucocorticoid receptor, increased mitochondrial density) leading to a reduction in telomere maintenance mechanisms (i.e. decrease in the gene expression of telomerase and protective shelterin). Additionally, medium-term survival was reduced from 34% in control nests to 19% in heated nests. Our results thus suggest that climate warming might affect cellular ageing in wild passerine populations, with potential impact on population dynamics and persistence.

Underline digital video library

Cultural evolution after environmental stress: a case study of songbird populations affected by the 2016 New York drought

Students' critical thinking skills in relation to climate change

Place-based education in high school physical science

Overview of Educational Applications of Lighter-Than-Air Ballooning

High Altitude Balloon Directional Measurements of Cosmic Ray Shower Events

The effects of simulated ocean acidification on the behaviour and physiology of the economically important Dungeness crab, Metacarcinus magister

Developmental plasticity in thermal tolerance: ontogenetic variation, persistence, and future directions

Are there differences in plasticity between populations within species?

A dangerous synergy of warming and hypoxia: the past and present for the future

Conserving threatened coastal wildlife during rapid environmental change: using biological responses to inform management strategies of giant clams

Mechanisms of parallel adaptation in a widespread copepod

From climate warming to accelerated cellular ageing: insights from two experimental studies in wild passerine birds

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