Beyond pairwise mechanisms of species coexistence in complex communities

Abstract

The tremendous diversity of species in ecological communities has motivated a century of research into the mechanisms that maintain biodiversity. However, much of this work examines the coexistence of just pairs of competitors. This approach ignores those mechanisms of coexistence that emerge only in diverse competitive networks. Despite the potential for these mechanisms to create conditions under which the loss of one competitor triggers the loss of others, we lack the knowledge needed to judge their importance for coexistence in nature. Progress requires borrowing insight from the study of multitrophic interaction networks, and coupling empirical data to models of competition.

Linking ecology and plant pathology to unravel the importance of soil-borne fungal pathogens in species-rich grasslands

“…Also the role of other players in the root microbiome can be incorporated (Mendes et al 2011;Berendsen et al 2018). A multi-species approach, rather than pairwise interactions, can reveal potential (synergistic) mechanisms that act only in diverse systems, as was recently suggested for fungal-bacterial (de Boer 2017) and plant-plant (Levine et al 2017) interactions.…”

Interaction modifications lead to greater robustness than pairwise non-trophic effects in food webs

“…It is possible that higher-order interactions are stabilising against small 365 perturbations, which may make the system as a whole more susceptible to large impacts, such as 366 the extinction of certain species (Levine et al, 2017). TIMs also have the potential to create the 367 necessary positive feedback structures to maintain alterative stable states (Holt & Barfield, 2013;368 Kéfi, Holmgren, & Scheffer, 2016).…”

“…Calls to incorporate the full panoply of non-trophic effects into our understanding of ecological 89 networks have built substantially in recent years (Fontaine et al, 2011;Ings et al, 2009;Kéfi et al, 90 2012;Levine et al, 2017;Ohgushi et al, 2012;Olff et al, 2009) and the first empirical inventories are 91 being established (Kéfi et al, 2015;Kéfi, Miele, Wieters, Navarrete, & Berlow, 2016). Theoretical 92 analyses can play a significant role in guiding the empirical creation of networks, identifying the 93 information necessary to best understand these systems.…”

“…There is a building appreciation that to improve our understanding of the population dynamics of 37 ecological communities it is necessary to move beyond studies that focus on a single interaction 38 process at a time (Kéfi et al, 2012;Levine, Bascompte, Adler, & Allesina, 2017). Trophic interaction 39 modifications (Terry, Morris, & Bonsall, 2017;Wootton, 1993) are class of higher-order process 40…”

Classifying forest inventory data into species-based forest community types at broad extents: exploring tradeoffs among supervised and unsupervised approaches

“…And, as forests change in response to climate and land use, characterization and classification of their species assemblages can aid in understanding reference conditions, monitoring changes in species composition over time, and detecting early warning signs of vulnerability to those global changes (Tierney et al 2009). While much of climate change impact and vulnerability research emphasizes the responses of individual species, focusing on communities allows incorporation of the relative occurrence of species-that is, the dominance (or conversely, the evenness) of species (Hildebrand et al 2008; Levine et al 2017). The relative occurrence of species in a forest ecosystem can influence species interactions, and is also likely to be influenced by environmental changes (Kardol et al 2010;Le Roux et al 2014).…”