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The U.S. National Parks encompass a variety of biophysical and historical resources important for national cultural heritage. Yet how these resources are socially constructed often depends on the beholder. Parks tend to be conceptualized according to their (fixed) geographic context, so our understanding of this system of systems is dominated by this geographic lens. To expose the systemic structure that exists beyond their geographic embedding, we analyze three representations of the National Park System using park–park similarity networks according to their cooccurrence in (1) about 423,000 news media articles; (2) about 11,000 research publications; and (3) about 60,000 species inhabiting parks. We quantify structural variation between network representations by leveraging similarity measures at different scales: park level (park–park correlations) and system level (network communities' consistency). Because parks are governed and experienced at multiple scales, cross-network comparison informs how management should account for the varying objectives and constraints that dominate at each scale. Our results identify an interesting paradox: Whereas park-level correlations depend strongly on the representative lens, the network communities are remarkably robust and consistent with the underlying geographic embedding. Our data-driven methodology is generalizable to other geographically embedded socioenvironmental systems and supports the holistic analysis of systems-level structure that might elude other approaches. [ABSTRACT FROM AUTHOR]

Aim: Mammalian carnivores are among the best studied groups in terms of evolutionary history. However, the effects of species interactions in shaping community assemblages remain poorly understood. We hypothesize that indirect interactions via ecological trait filtering play a key role in structuring carnivoran assemblages, mediate coexistence and thus should show high functional diversity (FD) in space and time at continental scales. Location: The Americas. Taxon Mammalian carnivores (Mammalia: Carnivora). Methods: We followed a macroecological perspective via ecological network analyses for indirect interactions and assessed the underlying FD across space and from the last interglacial to the present in the Americas. We analysed the potential distributions and six ecological traits of 88 species to establish possible mechanisms that enables species to coexist and the underlying diversity patterns. We compared the empirical results with two null models and two sensitivity analyses. Results: Co‐occurring carnivore species presented ecological segregation driven mainly by a size ratio (SR) relationship, called here the body size spatial anti‐clustering effect. The underlying FD patterns showed low redundancy towards the tropics and the poles during the times evaluated. However, during the last glacial maximum, shifts occurred primarily at high latitudes in North America. This shift affected the SR relationship and therefore changed FD patterns. These local‐to‐continental interactions mediated by the SR are significant from an ecological and biogeographic perspective, suggesting a robust and consistent trend in which carnivore species of similar size have a lower probability of occupying the same area unless they differentiate in other ecological trait spaces. Main conclusions: The SR relationship is potentially a primary mechanism limiting carnivore coexistence, reflecting functional filtering. The SR tends to be conservative across different ecological trait groups and through time and space. We propose that the body‐size spatial anti‐clustering effect can directly measure species' coexistence and mediate FD patterns in the Americas. [ABSTRACT FROM AUTHOR]

We develop a quantitative framework for understanding the class of wicked problems that emerge at the intersections of natural, social, and technological complex systems. Wicked problems reflect our incomplete understanding of interdependent global systems and the systemic risk they pose; such problems escape solutions because they are often ill-defined, and thus mis-identified and under-appreciated by communities of problem-solvers. While there are well-documented benefits to tackling boundary-crossing problems from various viewpoints, the integration of diverse approaches can nevertheless contribute confusion around the collective understanding of the core concepts and feasible solutions. We explore this paradox by analyzing the development of both scholarly (social) and topical (cognitive) communities — two facets of knowledge production studies here that contribute towards the evolution of knowledge in and around a problem, termed a knowledge trajectory — associated with three wicked problems: deforestation, invasive species, and wildlife trade. We posit that saturation in the dynamics of social and cognitive diversity growth is an indicator of reduced uncertainty in the evolution of the comprehensive knowledge trajectory emerging around each wicked problem. Informed by comprehensive bibliometric data capturing both social and cognitive dimensions of each problem domain, we thereby develop a framework that assesses the stability of knowledge trajectory dynamics as an indicator of wickedness associated with conceptual and solution uncertainty. As such, our results identify wildlife trade as a wicked problem that may be difficult to address given recent instability in its knowledge trajectory. [ABSTRACT FROM AUTHOR]