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Poster presented at NSTA 2026 

Host–parasite communities are shaped by the tension between evolutionary constraints and ecological opportunity. Digenetic trematodes, which rely on snail hosts to produce diverse larval stages, offer a powerful system to test hypotheses about evolutionary conservatism and ecological flexibility with implications for community structure. Across 120 sites spanning three ecoregions, 6.5% of 14,623 snails were infected by trematodes. Sequencing (18S and 28S) from 104 cercariae among 12 morphotypes revealed 22 trematode families concentrated in a few keystone host taxa. Model‐based analyses showed that cercaria morphotypes exhibited nearly perfect phylogenetic signal. In contrast, host use, defined by the snail lineages each trematode infects, evolves under an Ornstein–Uhlenbeck model of stabilizing selection. This asymmetry indicates that cercaria morphotypes are evolutionarily stable relative to host use, which remains flexible but bounded within an adaptive landscape. Our data elucidate complex life cycles, uncovers parasite diversity maintained by keystone host taxa and reveals recurrent ‘evolutionary reunions’, in which distantly related trematodes revisit ancestral snail associations through ecological fitting and adaptations toward common host lineages. Evolutionary reunions help resolve the long‐standing parasite paradox—how parasites remain specialized yet occasionally capture or shift hosts—by demonstrating that host–parasite evolution is not a linear process of continual novelty but a dynamic interplay of constraint, contingency and opportunity. Together, these findings provide a molecular framework linking evolutionary and ecological processes to identify general rules of symbiotic interrelationships, with implications for predicting the origins of emerging diseases, the persistence of coevolutionary networks and biodiversity responses to environmental change. 

Abstract Multiscale geographically weighted regression (MGWR) extends geographically weighted regression (GWR) by allowing process heterogeneity to be modeled at different spatial scales. While MGWR improves parameter estimates compared to GWR, the relationship between spatial scale and correlations within and among covariates—specifically spatial autocorrelation and collinearity—has not been systematically explored. This study investigates these relationships through controlled simulation experiments. Results indicate that spatial autocorrelation and collinearity affect specific model components rather than the entire model. Their impacts are cumulative but remain minimal unless they become very strong. MGWR effectively mitigates local multicollinearity issues by applying varying bandwidths across parameter surfaces. However, high levels of spatial autocorrelation and collinearity can lead to bandwidth underestimation for global processes, potentially producing false local effects. Additionally, strong collinearity may cause bandwidths to be overestimated for some processes, which helps mitigate collinearity but may obscure local effects. These findings suggest that while MGWR offers greater robustness against multicollinearity compared to GWR, bandwidth estimates should be interpreted with caution, as they can be influenced by strong spatial autocorrelation and collinearity. These results have important implications for empirical applications of MGWR. 

Abstract The implementation of coastal nature-based features, created wetlands, and wetland restoration has increased globally over recent years. Many of these projects have been successful in meeting their goals, however, when projects fail, it is often attributed to mortality of transplanted vegetation. Transplant mortality may be due to inappropriate timing, poor site selection, or abiotic stressors associated with transplant shock. Science-backed guidelines have been well established in many coastal regions regarding site specifications and species selection, but nursery practices for reducing transplant shock remain inconsistent. In this study, we tested a combination of four salinity acclimation treatments and two inundation acclimation treatments on nursery-grownSpartina alternifloraandS. patensplugs. We measured a suite of plant functional traits to determine tradeoffs in plant response with a focus on traits associated with plant marketability, indicators of stress acclimation, and desired traits for restoration goals. A subset of plants was transplanted to a restoration site for analysis of their survival in situ. Exposure to salinity and inundation resulted in traits associated with both marketability and restoration goals (e.g., increased stem height, reduced dead to live stem ratio, and increased biomass), as well as evidence of acclimation to field stressors. However, trait differences did not translate to differences in field performance as survival and expansion of transplanted individuals showed no difference between acclimation treatments. The future of coastal wetland creation and restoration will require plant material that is produced using a science-based approach to ensure plants are robust, long-lived, and marketable to achieve the needs to restoration and nursery practitioners alike. 

In order to promote justice-centered making in STEAM classrooms, the NASA Landsat-based Science and Technology Education for Land/Life Assessment (STELLA) instrument is proposed as an affordable educational tool for students to collect and analyze data pertaining to vegetation health, surface temperature, and air quality. This instrument can be used to investigate justice-centered, community-based problems and promote civic engagement toward policy change for a healthier world. Our study applies the MakerTPICK theoretical framework to a qualitative study to explore changes in teacher beliefs about the STELLA instrument following three justice-centered STEAM-making activities pertaining to urban heat islands, air quality, and vegetation health. The implications of this research can be used to inform professional development and promote justice-centered learning in the STEAM classroom. 

In this session, we will share our model for K-5 STEM teacher leadership. 

The etching of ZnO thin films using acetylacetone (Hacac) doses with long exposure times, followed by purging and subsequent exposure to O2 plasma, is studied in a hot-wall reactor using simultaneous in situ spectroscopic ellipsometry and quadrupole mass spectrometry. The static exposure step results in the efficient consumption of Hacac. For each etch cycle, the O2 plasma plays a crucial role in removing unreacted Hacac from the ZnO surface, priming the surface for subsequent Hacac etching. This is confirmed by the production of CO2 during the O2 plasma pulse. The temperature window for etching is established as 220–280 °C with a maximum etch per cycle (EPC) of 0.15 nm/cy. Under these conditions, the Hacac pulse is 2 s long with a 30 s static hold step followed by 5 s O2 plasma step at 300 W power. Statistical analyses of etch data at the granularity level of each cycle reveal the importance of the static hold step in determining EPC. Arrhenius behavior of etching during the hold step reveals a piecewise linear trend with a low temperature (120–200 °C) activation energy (Ea) of 202 meV and a high temperature (200–320 °C) Ea of 32 meV. It is shown that saturation behavior in EPC is pulse time and static hold time dependent. Shorter Hacac pulses (≤1 s) demonstrate saturation behavior for static hold times ∼30 s, longer pulses of Hacac (≥2 s) show no saturation in EPC with static hold times up to 75 s.