Much of Illinois was once wet prairie, dotted with ancient (ca. 10,000‐year‐old) ephemeral wetlands. Most wetland habitat (85%) was converted to agriculture over a span of about 100 years (ca. 1850–1950). The consequences of this severe habitat fragmentation on wetland communities and metapopulations are unknown. We studied crustacean communities (weekly stovepipe samples throughout hydroperiods) for 3 years in a set of extant ephemeral wetlands in Illinois. We generated species‐sites curves by rarefaction and extrapolated those curves to conservatively estimate that 83–85 crustacean species may have inhabited approximately 4 million ephemeral wetlands that once existed in Illinois; 8–9 crustacean species were driven to extinction in Illinois during drainage; and 75–76 crustacean species are extant in the few remaining ephemeral wetlands of Illinois. We also conducted cellular automata simulations to examine the potential effects of habitat fragmentation on the genetic structure of extant crustacean metapopulation. Simulations indicated that conversion of the former wet prairie to agriculture may have reduced crustacean metapopulations to isolated populations that are more vulnerable to future habitat loss. Despite severe habitat fragmentation, curvilinear species‐sites relationships suggest that the greatest extinction rates have yet to occur for ephemeral wetland crustaceans. However, selection for limited dispersal during habitat fragmentation may contribute to extinction debt for extant species. Conservation programs can preserve much of the historical biodiversity of ephemeral wetlands, but future wetland biodiversity will depend heavily on the success of those efforts. The consequences of historical wetland loss and the importance of wetland conservation efforts to agriculture in the United States should be instructive for other regions.

Peer Instruction (PI) is a student-centric pedagogy in which students move from the role of passive listeners to active participants in the classroom. Over the past five years, there have been a number of research articles regarding the value of PI in computer science. The present work adds to this body of knowledge by examining outcomes from seven introductory programming instructors: three novices to PI and four with a range of PI experience. Through common measurements of student perceptions, we provide evidence that introductory computing instructors can successfully implement PI in their classrooms. We find encouraging minimum (74%) and average (92%) levels of success as measured through student valuation of PI for their learning. This work also documents and hypothesizes reasons for comparatively poor survey results in one course, highlighting the importance of the choice of grading policy (participation vs. correctness) for new PI adopters.

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Software technology for algorithm visualization (AV) has advanced faster than our understanding of how such technology impacts student learning. In this paper we present results of a multi-university study. We measured the effect of varying levels of student engagement with AV to learn simple sorting algorithms. These levels included: 1) not seeing any visualization, 2) simply viewing visualizations for a short period in the classroom, and 3) interacting directly with the visualizations for an extended period outside of the classroom. Our results show that learning increases as the level of student engagement increases. AV has a bigger impact on learning when students go beyond merely viewing a visualization and are required to engage in additional activities structured around the visualization. In particular, students who responded to questions integrated into the AV tool during their exploration of an algorithm showed the most improvement between a pretest and posttest.

Student-centered instructional practices structure a class so that students interact with each other, engage deeply with the content, and receive formative feedback. These evidence-based practices benefit all students but are particularly effective with underrepresented learners, including women and members of other minority groups. To what extent have computer science (CS) faculty embraced these strategies? We surveyed over 700 U.S. faculty to find out. Results suggest that female faculty, associate professors, and those teaching courses with enrollment above 80 students are more likely to use these student-centered practices. Across all responses, 20% of faculty use student--student interaction on a regular basis during class. In contrast, 38% of faculty rely on lectures for content delivery. Results were also compared with published data for other academic disciplines. CS faculty are less likely to use these practices compared to their non-STEM colleagues but more likely to use these practices compared to other STEM discipline faculty. Overall, CS faculty have adopted student-centered practices to some degree, but our community should strive for higher adoption rates to help as many students as possible learn and remain in computer science.