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Immune systems pose fascinating puzzles for evolutionary biologists. They feature some of the most polymorphic genes and reflect the strongest natural selection known. Evolution of immune systems plays a key role in host–parasite interactions, speciation, and eco-evolutionary dynamics that have community- and ecosystem-wide consequences. Conversely, evolutionary perspectives enrich our understanding of immunology, revealing macroevolutionary origins of key immune traits, their function in wild populations as opposed to sterile lab settings, and trade-offs that constrain immune adaptation. Here, we review key themes in the fast-growing interdisciplinary field of evolutionary immunology, focusing on multicellular animals. We describe macroevolution of immune functions, evidence of contemporary selection on immune genes, and the underlying theory seeking to explain this selection at multiple biological scales. We identify major open questions and opportunities in the field today. Foremost among these is the challenge of accurately and appropriately measuring relevant immune traits in wild and nonmodel organisms, which is necessary to understand their evolution in natural settings. A second challenge is to describe how diverse communities of symbionts impose selection on the highly multivariate and pleiotropic immune system. 

People sometimes change their opinions when they discuss things with each other. Researchers can use mathematics to study opinion changes in simplifications of real-life situations. These simplified scenarios, which are examples of mathematical models, help researchers explore how people influence each other through their social interactions. In today’s digital world, these models can help us learn how to promote the spread of accurate information and reduce the spread of inaccurate information. In this article, we discuss a simple mathematical model of opinion changes that arise from social interactions. We briefly describe what opinion models can tell us and how researchers try to make them more realistic. 

ABSTRACT Many terrestrial ectotherms have gone to great evolutionary lengths to adapt to long cold winters; some have even evolved the ability to tolerate the freezing of most of the extracellular fluid in the body. Now, however, high‐elevation and high‐latitude winters are experiencing an accelerated period of warming. Specialised winter adaptations that promoted fitness in a seasonally frozen environment may soon be superfluous or even maladaptive. We ask whether winter adaptations include changes in immune functions, and whether changing winter conditions could exert disparate effects on populations of a wide‐ranging terrestrial ectotherm, the wood frog (Lithobates sylvaticus). By rearing wood frogs from ancestral winter environments that vary in length and temperature in a common garden, and reciprocally exposing post‐metamorphic frogs to unfrozen and frozen artificial winter conditions in the lab, we were able to decompose transcriptomic differences in ventral skin gene expression into those that were environmentally induced (responsive to temperature) and genetically determined and those that varied as an interaction between the genotype and environment. We found that frogs from harsh ancestral winter environments constitutively upregulated immune processes, including cellular immunity, inflammatory processes and adaptive immune processes, as compared to frogs from mild ancestral winter environments. Further, we saw that the expression of several genes varied in an interaction between the genotype and artificial winter. We suggest that just as winter climates likely served as the selective force resulting in remarkable winter adaptations such as freeze tolerance, they may have also induced constitutive changes in immune gene expression. 

Bifunctional molecules such as targeted protein degraders induce proximity to promote gain‐of‐function pharmacology. These powerful approaches have gained broad traction across academia and the pharmaceutical industry, leading to an intensive focus on strategies that can accelerate their identification and optimization. We and others have previously used chemical proteomics to map degradable target space, and these datasets have been used to develop and train multiparameter models to extend degradability predictions across the proteome. In this study, we now turn our attention to develop generalizable chemistry strategies to accelerate the development of new bifunctional degraders. We implement lysine‐targeted reversible‐covalent chemistry to rationally tune the binding kinetics at the protein‐of‐interest across a set of 25 targets. We define an unbiased workflow consisting of global proteomics analysis, IP/MS of ternary complexes and the E‐STUB assay, to mechanistically characterize the effects of ligand residence time on targeted protein degradation and formulate hypotheses about the rate‐limiting step of degradation for each target. Our key finding is that target residence time is a major determinant of degrader activity, and this can be rapidly and rationally tuned through the synthesis of a minimal number of analogues to accelerate early degrader discovery and optimization. 

Recent reports of insect declines have raised concerns about the potential for concomitant losses to ecosystem processes. However, understanding the causes and consequences of insect declines is challenging, especially given the data deficiencies for most species. Needed are approaches that can help quantify the magnitude and potential causes of declines at levels above species. Here we present an analytical framework for assessing broad‐scale plant–insect phenologies and their relationship to community‐level insect abundance patterns. We intentionally apply a species‐neutral approach to analyse trends in phenology and abundance at the macroecological scale. Because both phenology and abundance are critical to ecosystem processes, we estimate aggregate metrics using the overwintering (diapause) stage, a key species trait regulating phenology and environmental sensitivities. This approach can be used across broad spatiotemporal scales and multiple taxa, including less well‐studied groups. Using community (‘citizen’) science butterfly observations from multiple platforms across the Eastern USA, we show that the relationships between environmental drivers, phenology and abundance depend on the diapause stage. In particular, egg‐diapausing butterflies show marked changes in adult‐onset phenology in relation to plant phenology and are rapidly declining in abundance over a 20‐year span across the study region. Our results also demonstrate the negative consequences of warmer winters for the abundance of egg‐diapausing butterflies, irrespective of plant phenology. In sum, the diapause stage strongly shapes both phenological sensitivities and developmental requirements across seasons, providing a basis for predicting the impacts of environmental change across trophic levels. Utilizing a framework that ties thermal performance across life stages in relation to climate and lower‐trophic‐level phenology provides a critical step towards predicting changes in ecosystem processes provided by butterflies and other herbivorous insects into the future. 

One intervention thought to foster women’s interest in engineering is introducing girls to STEM or engineering activities. The argument for this is that an increase in interest early in their lives will lead to more women pursuing a career in engineering. The focus of our research is women who are thriving as undergraduate student leaders in engineering project teams. We employ a multi-case study method that involves a sequence of semi-structured interviews. This paper speaks to the findings derived from the life history interview where participants describe their early lives and pre-college education. Our inductive thematic analysis of the data indicates that: (1) The women’s early familial influences allowed non-gender defined ways of being, doing, and aspiring for trying new things. (2) This re/definition of gender in relation to self is reinforced by their success in school and through their accomplishments in other extracurricular activities. Those activities were not confined or even heavily weighted toward STEM. (3) Not all of the women assumed leadership roles throughout their K-12 schooling. Nevertheless, what is common is that through academic and extracurricular engagements they developed confidence, a “can-do” attitude, and a rejection of viewing failures as defining indicators of their ability or potential. Their self-awareness, their confidence, and their persistence in the face of failure are critical because they later function as counter-narratives in the women’s encounters with sexism and other forms of marginalization when in engineering and their project teams. Finally, there is some evidence to suggest that encouraging young girls to involve themselves in STEM and/or engineering may be counterproductive. By unintentionally “pushing” these young girls into engineering, rather than “allowing them to choose for themselves,” we may be encouraging the adoption of masculinist gendered roles associated with engineering.