Small mammal personalities generate context dependence in the seed dispersal mutualism

Abstract

Significance Mutualisms are foundational components of ecosystems and give rise to essential services such as seed dispersal and pollination. Ecologists believe that nearly every species is involved in one or more mutualisms, but it is unknown how consistent behavioral differences among individuals, or personalities, may influence an individual’s role. We scored individuals on a continuum from antagonistic to mutualistic given their contributions to the seed dispersal mutualism and found that personalities affect the extent to which individuals are mutualistic. These findings suggest a novel mechanism generating context dependence in mutualisms and underscore the need to incorporate behavioral diversity into conservation and restoration efforts.

Predation risk and personality influence seed predation and dispersal by a scatter‐hoarding small mammal

“…This was inevitable due to the nature of our field study being conducted with free‐ranging individuals and is likely reflected in the relatively large CI on our predictions. We emphasize that this number is in line with work from similar field studies (Brehm & Mortelliti, 2022; Martin & Réale, 2008) and includes data from a greater number of seed selection events. Further studies conducted in other settings will contribute to generalize our results.…”

“…The key decisions made by small mammals, and therefore the fate of encountered seeds, are affected by seed traits such as size, perishability, nutrient level, and tannin content, and small mammal's internal energetic state (Hadj‐Chikh et al, 1996; Steele et al, 2014; Wang et al, 2013; Wang & Corlett, 2017; Yi & Wang, 2015). Additionally, all of these decisions are mediated by individual personality (Boone et al, 2022; Brehm et al, 2019), that is, consistent individual behavioral differences across contexts (Dingemanse et al, 2012; Réale et al, 2007; Sih et al, 2004), ultimately affecting the outcome of this conditional mutualism (Brehm & Mortelliti, 2022).…”

Intraspecific variation in seed size is mediated by seed dispersal modes and animal dispersers – evidence from a global‐scale dataset

“…The present study focusses on seed size as a case study, although intraspecific variation is prevalent in numerous other plant traits (Shimada et al ., 2015; Muiruri et al ., 2019; Vega‐Polanco et al ., 2023). Additionally, animals exhibit remarkable intraspecific trait variation, such as personality, body mass, and foraging preference (Toïgo et al ., 2006; Milles et al ., 2020; Brehm & Mortelliti, 2022). Integrating these intraspecific variations in plant and animal traits into pertinent investigations will enhance our comprehensive understanding of ecosystem stability and development.…”

Modeling the continua in the outcomes of biotic interactions

“…The only extra information that our model requires with respect to previous models is the distribution of immediate outcomes of interaction events. Although gathering this information could be considered a difficult task, this approach is already taken by field ecologists working on interaction effectiveness, interaction intensity, coevolution, eco-evolutionary dynamics, individual specialization, or individual-based networks (e.g., Bolnick et al, 2003;Brehm & Mortelliti, 2022;G omez et al, 2019;Thompson, 1988Thompson, , 2005. To show the applicability of our model, we briefly describe here some aspects of the natural history of a few interactions to show how the distribution of immediate outcomes of interaction events is routinely assessed.…”

“…A proportion of aphid genotypes increase their survival when infected by the symbiont Regiella insecticola (positive immediate outcomes) but another proportion decreases (negative immediate outcomes) (Parker et al, 2021). In fact, dual outcomes occur in a wide variety of interactions, whether symbiotic (DiSalvo et al, 2015; Johnson and Graham, 2013; Johnson et al, 1997; Lin & Koskella, 2015; Mandyam & Jumpponen, 2015; Parker et al, 2021; Regus et al, 2015; Sachs & Wilcox, 2006; Saikkonen et al, 1998), or non‐symbiotic mutualistic (Brehm & Mortelliti, 2022; Gómez et al, 2019; Navarro, 2000; Quinn & Kokorev, 2002), antagonistic (Belsky et al, 1993; Carper et al, 2016; Delibes et al, 2017; Green & Sánchez, 2006; Maschinski & Whitham, 1989; Paige & Whitham, 1987; Polis et al, 1989), or competitive interactions (Butterfield & Callaway, 2013; Callaway & Walker, 1997). Remarkably, dual outcomes can also occur in traditionally considered fixed interactions.…”