Incorporating human behaviors into theories of urban community assembly and species coexistence

Abstract

In cities, humans directly and indirectly affect plant and wildlife communities. These human-species interactions are not included in traditional ecological approaches used to understand why and how organisms are distributed. Here, we incorporate human behaviors into urban community assembly theories and detail all the complex ways humans affect the dispersal, selection and persistence of species in cities. To do this, we integrate human behaviors and actions into traditional filter frameworks used to study community assembly. We use our framework to develop testable hypotheses to predict patterns of urban diversity as well as pose key considerations for future research. In order to have a predictive understanding of how urban biodiversity responds to environmental, social and land use change, it is necessary to better understand interactions between humans and other organisms.

Tree communities in Baltimore differ by land use type, but change little over time

“…Our results indicate that tree urban community composition varies more by land use than it does over time, although some land uses (i.e., transportation and institutional lands) may be more dynamic than others. Urban plant communities may be emergent, planted, or remnants of native vegetation (Williams et al, 2009), and processes that affect community composition likely differ by management intensity (Avolio et al, 2021). For example, transportation or vacant land is likely to have less human management and more opportunities for spontaneous tree communities to arise.…”

A trait-based conceptual framework to examine urban biodiversity, socio-ecological filters, and ecosystem services linkages

“…1 and 2). Ecological traits represent the combinations of traits of native species in the bioregion, which naturally and spontaneously disperse to urban systems without direct human intervention 25,26 . For example, many traits associated with species of fungi and microbes, invertebrates, plants, and vertebrates naturally disperse to urban areas.…”

“…For example, many traits associated with species of fungi and microbes, invertebrates, plants, and vertebrates naturally disperse to urban areas. These species often present highly adaptative characteristics such as opportunistic behaviors, that allow them to thrive in urban environments (for example, raccoons) 26 . Anthropogenic traits represent combinations of traits of species introduced to urban systems through human-mediated dispersion 25,26 .…”

“…These species often present highly adaptative characteristics such as opportunistic behaviors, that allow them to thrive in urban environments (for example, raccoons) 26 . Anthropogenic traits represent combinations of traits of species introduced to urban systems through human-mediated dispersion 25,26 . These species can be intentionally or unintentionally dispersed and can be sourced from anywhere in the world.…”

“…According to the authors, ecological filters related to the urban environment (for example, atmospheric pollution and high temperatures), can lead to traits narrowing or shifts to traits that are able to withstand those environmental conditions. In addition, human preferences can also lead to functional shifts, due to the introduction of new species, or traits narrowing, due to species eradication; in 2016, Aronson and colleagues 27 introduced a hierarchical filters approach, where environmental and social filters successively remove species based on their traits, affecting species distribution and community assemblages; other authors have studied how social filters related to management decisions, preferences, and residents' socioeconomic and cultural backgrounds influence trait distribution in urban areas [34][35][36] ; more recently, Avolio et al 26 introduced a framework where species selection, local environmental conditions, biotic interactions, and overall human behavior affect the Fig. 2 The different trait combinations considered by the Socio-Ecological Traits Framework.…”