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The Vision and Change report called for the biology community to mobilize around teaching the core concepts of biology. This essay describes a collection of resources developed by several different groups that can be used to respond to the report’s call to transform undergraduate education at both the individual course and departmental levels. First, we present two frameworks that help articulate the Vision and Change core concepts, the BioCore Guide and the Conceptual Elements (CE) Framework, which can be used in mapping the core concepts onto existing curricula and designing new curricula that teach the biology core concepts. Second, we describe how the BioCore Guide and the CE Framework can be used alongside the Partnership for Undergraduate Life Sciences Education curricular rubric as a way for departments to self-assess their teaching of the core concepts. Finally, we highlight three sets of instruments that can be used to directly assess student learning of the core concepts: the Biology Card Sorting Task, the Biology Core Concept Instruments, and the Biology—Measuring Achievement and Progression in Science instruments. Approaches to using these resources independently and synergistically are discussed.

Global urban development continues to accelerate and have diverse effects on wildlife. Although most studies of anthropogenic impacts on animals have focused on indirect effects (e.g., environmental modifications like habitat change or pollution), there may also be direct effects of physical human presence and actions on wildlife stress, behavior, and persistence in cities. Most studies on how humans physically interact with wildlife have focused on the active, daytime phase of diurnal animals, rarely considering effects of our night-time activities. We hypothesized that, if night-time human presence is a stressor for wildlife that are not commonly exposed to humans, night-disturbed rural animals would show stronger physiological signs of elevated stress than would urban individuals. Specifically, we experimentally investigated the effects of human presence at night (HPAN) on disease, body mass, and mass-specific metabolic rates in urban- and rural-caught house finches (Haemorhous mexicanus) in captivity. Our HPAN treatment consisted of a human entering the housing room of the birds and briefly jostling the home cages of each finch as the person walked around the room for a 3-min period on five randomly selected nights per week. Compared with a control (night-undisturbed) group, we found that HPAN greatly increased the odds finches were awake for ca. 33 min post-disturbance, but that chronic treatment did not alter body mass, parasitic infection by coccidian endoparasites, or mass-specific basal metabolic rates. Additionally, finches caught from urban and rural sites did not differ in their response to the treatment. Overall, our results are consistent with those showing that brief but regular human disturbances can have acute negative effects on wildlife, but carry few if any long-term metabolic or disease-related costs in fast-lived birds. However, these findings contrast with the broad, chronic physiological effects of other anthropogenic changes, such as artificial light at night, and highlight the differential impacts that various human activities (which differ in sensory stimulus type, perceived threat, duration and intensity, etc.) can have on wildlife health and behavior.

College instructors in the United States usually make their own decisions about how to design course exams. Even though summative course exams are well known to be important to student success, we know little about the decision making of instructors when designing course exams. To probe how instructors design exams for introductory biology, we conducted an exploratory interview study with seven instructors teaching the same introductory biology course at a large university. We found that despite designing exams for the same course, instructor exam decisions differed with regard to what content was assessed, the exam format, the cognitive difficulty of exam questions, the resources used when crafting exams, and how exams were administered. We hope that this work can initiate conversations about how college instructors should design exams and lead to more uniformity in how student learning is assessed across the same courses taught by different instructors.

International audience; 1. Parent–offspring conflicts are likely to occur when resources are limiting either at pre- orpost-natal stages due to intergenerational trade-offs over resources. Current theory posits thatsuch conflicts may influence the evolution of parental allocation as well as reproductive modes.While energy allocation to the offspring has received considerable attention, the distribution ofwater – another potentially limited vital resource to both the mother and offspring – and theresulting outcomes remain grossly understudied.2. Here, we explored the intergenerational trade-off related to water resources in the viviparousaspic viper (Vipera aspis) by examining the effects of water deprivation on female physiology(body mass, haematocrit and osmolality), water transfer to developing embryos andreproductive performance.3. As a result of water deprivation, females became dehydrated, with the effects more pronouncedin pregnant compared to nonreproductive females. Among pregnant females,the impacts of water deprivation on water balance were correlated with fecundity. Incontrast, water deprivation had no effect on water transfer to the offspring or on reproductiveperformance.4. Our results demonstrate that, under water-constraining conditions, female water balance iscompromised in favour of the developing embryos, highlighting a significant intergenerationaltrade-off for water. Although ectothermic reptiles are particularly tolerant in water balanceperturbations, our results suggest that, like energy, water can be a conflicting resourcebetween mother and offspring. Parent–offspring conflict over water should therefore befurther investigated to better understand reproductive modes and reproductive trade-offs interrestrial organisms.

The Vision and Change report provides a nationally agreed upon framework of core concepts that undergraduate biology students should master by graduation. While identifying these concepts was an important first step, departments also need ways to measure the extent to which students understand these concepts. Here, we present the General Biology–Measuring Achievement and Progression in Science (GenBio-MAPS) assessment as a tool to measure student understanding of the core concepts at key time points in a biology degree program. Data from more than 5000 students at 20 institutions reveal that this instrument distinguishes students at different stages of the curriculum, with an upward trend of increased performance at later time points. Despite this trend, we identify several concepts that advanced students find challenging. Linear mixed-effects models reveal that gender, race/ethnicity, English-language status, and first-generation status predict overall performance and that different institutions show distinct performance profiles across time points. GenBio-MAPS represents the first programmatic assessment for general biology programs that spans the breadth of biology and aligns with the Vision and Change core concepts. This instrument provides a needed tool to help departments monitor student learning and guide curricular transformation centered on the teaching of core concepts.

SUMMARY Many xeric organisms maintain water balance by relying on dietary and metabolic water rather than free water, even when free water may be available. For such organisms, hydric state may influence foraging decisions, since meal consumption is meeting both energy and water demands. To understand foraging decisions it is vital to understand the role of dietary water in maintaining water balance. We investigated whether meal consumption was sufficient to maintain water balance in captive Gila monsters (Heloderma suspectum) at varying levels of dehydration. Gila monsters could not maintain water balance over long time scales through meal consumption alone. Animals fed a single meal took no longer to dehydrate than controls when both groups were deprived of free water. Additionally, meal consumption imparts an acute short-term hydric cost regardless of hydration state. Meal consumption typically resulted in a significant elevation in osmolality at 6 h post-feeding, and plasma osmolality never fell below pre-feeding levels despite high water content (~70%) of meals. These results failed to support our hypothesis that dietary water is valuable to Gila monsters during seasonal drought. When considered in conjunction with previous research, these results demonstrate that Gila monsters, unlike many xeric species, are heavily reliant on seasonal rainfall and the resulting free-standing water to maintain water balance.

International audience; Water is a crucial resource that can profoundly impact the biology of terrestrial organisms. Early life stages are particularly sensitive to hydric constraints because water uptake is an important component of embryonic development. While amniotic eggs constitute a key innovation to terrestrial life, many vertebrates are viviparous wherein the mother must be the source of water for her developing embryos. Since most viviparous squamates are lecithotrophic (i.e., energy is supplied to the offspring as yolk deposited into pre-ovulated follicles), water is the predominant resource allocated from the mother to the offspring during development. Contrary to energy that can be stored (e.g., as fat reserves), water typically cannot be acquired in advance. Therefore, the embryos' need for water can impose significant constraints on the pregnant female. We detailed water flux during pregnancy in a viviparous snake, the aspic viper (Vipera aspis). We found that embryonic water uptake occurred mostly during the second half of pregnancy—a period dominated by somatic growth. We also found that, somewhat unexpectedly, changes in female plasma osmolality were negatively related to fecundity. This latter result suggests that water consumption by the female is especially important for large litter sizes, and thus may suggest an important sensitivity of reproductive females to environmental water availability.

We studied an Ambystoma maculatum (Spotted Salamander) population whose available terrestrial habitat varied in forest age, forest extent, and edge type to determine how microhabitats differed among habitats, whether A. maculatum displayed a nonrandom distribution of inbound capture locations, and whether individuals captured in different locations differed in age, body condition, and annual recapture rate. In this study, we use inbound capture location to infer direction of migration. Given this inference and the results of principle components analyses on surrounding habitat variables, we suggest that habitat differences in relation to litter depth, canopy cover, and soil water content best described the nonrandom distribution of A. maculatum captures. Differences in forest extent and edge type may also have contributed substantially to the A. maculatum migration capture pattern. Female salamanders arriving from the direction of the relatively mature, extensive forested habitat were significantly older than those arriving from the direction of the mature habitat with an agricultural edge, but there were no age differences among males. Body condition and annual recapture rates were similar among individuals regardless of capture location. Consistent with other work, we suggest that habitat protection efforts for A. maculatum, and similar species, should focus on extensive, forested habitat, with high levels of leaf litter and canopy cover and well- drained soils. Additionally, residential and agricultural edges may be more permeable than road edges for this species.