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This study explores the relationships between peer-to-peer interactions and (1) group formation among students, (2) choice of research, and (3) course performance in an online asynchronous ecology course at a research-intensive university. Peer-to-peer interactions have been known to enhance learning experience for students in a wide array of contexts, including online courses. However, less is known about how these interactions shape the students' performance and their choice of research over the course of time. Most previous studies have focused on either large introductory-level courses, where peer-to-peer interactions are usually lower, or analyses across a large number of courses, which introduce additional sources of variance. To explore how online peer-to-peer interactions develop, influence course dynamics, and impact student success, we collected data from a single medium-sized ecology course about peer-to-peer interactions, course performance, and student demographics. The course was repeated over six different semesters with the same instructor, same teaching assistant (TA), and an unchanged course structure to maintain certain homogeneity. Average class size was 20-25 students, and the educational format required intense discussions and peer interactions. Adopting a network science approach to the analyses, we find that peer-to-peer interactions not only affect student performance, but also shape class-wide interactions (e.g., working group formation), and choice of course research topic. Understanding this interplay of peer-to-peer interactions, group formation, and choice of research is important in forging necessary skills in students for a variety of contexts, and through such insights might better shape teamwork and choice of research, which are very important for molding future scientists in the twenty-first century.

Accurately quantifying species' area requirements is a prerequisite for effective area-based conservation. This typically involves collecting tracking data on species of interest and then conducting home-range analyses. Problematically, autocorrelation in tracking data can result in space needs being severely underestimated. Based on the previous work, we hypothesized the magnitude of underestimation varies with body mass, a relationship that could have serious conservation implications. To evaluate this hypothesis for terrestrial mammals, we estimated home-range areas with global positioning system (GPS) locations from 757 individuals across 61 globally distributed mammalian species with body masses ranging from 0.4 to 4000 kg. We then applied block cross-validation to quantify bias in empirical home-range estimates. Area requirements of mammals 1, meaning the scaling of the relationship changed substantially at the upper end of the mass spectrum.

The influence of climate on deep-time plant-insect interactions is becoming increasingly well known, with temperature, CO2 increases (and associated stoichiometric changes in plants), and aridity likely playing a critical role. In our modern climate, all three factors are shifting at an unprecedented rate, with uncertain consequences for biodiversity. To investigate effects of temperature, stoichiometry (specifically that of nitrogen), and aridity on insect herbivory, we explored insect herbivory in three modern floral assemblages and in 39 fossil floras, especially focusing on eight floras around a past hyperthermal event (the Paleocene-Eocene Thermal Maximum) from Bighorn Basin (BB). We find that higher temperatures were associated with increased herbivory in the past, especially among BB sites. In these BB sites, non-N2-fixing plants experienced a lower richness but higher frequency of herbivory damage than N2-fixing plants. Herbivory frequency but not richness was greater in BB sites compared with contemporaneous, nearby, but less arid sites from Hanna Basin. Compared with deep-time environments, herbivory frequency and richness are higher in modern sites, suggesting that current accelerated warming uniquely impacts plant-insect interactions. Overall, our work addresses multiple aspects of climate change using fossil data while also contextualizing the impact of modern anthropogenic change on Earth's most diverse interactions. [ABSTRACT FROM AUTHOR]

Ecologists have long investigated how demographic and movement parameters determine the spatial distribution and critical habitat size of a population. However, most models oversimplify movement behaviour, neglecting how landscape heterogeneity influences individual movement. We relax this assumption and introduce a reaction–advection–diffusion equation that describes population dynamics when individuals exhibit space-dependent movement bias toward preferred regions. Our model incorporates two types of these preferred regions: a high-quality habitat patch, termed 'habitat', which is included to model avoidance of degraded habitats like deforested regions; and a preferred location, such as a chemoattractant source or a watering hole, that we allow to be asymmetrically located with respect to habitat edges. In this scenario, the critical habitat size depends on both the relative position of the preferred location and the movement bias intensities. When preferred locations are near habitat edges, the critical habitat size can decrease when diffusion increases, a phenomenon called the drift paradox. Also, ecological traps arise when the habitat overcrowds due to excessive attractiveness or the preferred location is near a low-quality region. Our results highlight the importance of species-specific movement behaviour and habitat preference as drivers of population dynamics in fragmented landscapes and, therefore, in the design of protected areas. [ABSTRACT FROM AUTHOR]

Increasing trade between countries and gains in income have given consumers around the world access to a richer and more diverse set of commercial plant products (i.e., foods and fibers produced by farmers). According to the economic theory of comparative advantage, countries open to trade will be able to consume more-in terms of volume and diversity-if they concentrate production on commodities that they can most cost-effectively produce, while importing goods that are expensive to produce, relative to other countries. Here, we perform a global analysis of traded commercial plant products and find little evidence that increasing globalization has incentivized agricultural specialization. Instead, a country's plant production and consumption patterns are still largely determined by local evolutionary legacies of plant diversification. Because tropical countries harbor a greater diversity of lineages across the tree of life than temperate countries, tropical countries produce and consume a greater diversity of plant products than do temperate countries. In contrast, the richer and more economically advanced temperate countries have the capacity to produce and consume more plant species than the generally poorer tropical countries, yet this collection of plant species is drawn from fewer branches on the tree of life. Why have countries not increasingly specialized in plant production despite the theoretical financial incentive to do so? Potential explanations include the persistence of domestic agricultural subsidies that distort production decisions, cultural preferences for diverse local food production, and that diverse food production protects rural households in developing countries from food price shocks. Less specialized production patterns will make crop systems more resilient to zonal climatic and social perturbations, but this may come at the expense of global crop production efficiency, an important step in making the transition to a hotter and more crowded world.