Box 1. Carnivores as variable seed dispersal agents
Carnivores can be important agents of directed, long-distance dispersal
(Herrera 1989; Willson 1993; Rost et al. 2012; López-Bao et
al. 2015; Hämäläinen et al. 2017; Shakeri et al. 2018),
and rodent aversion to carnivore scat promotes the survival of
scat-dispersed seeds (Bartel & Orrock 2021). Individual niche
specialization (i.e., where intraspecific variation in seed dispersal
effectiveness should be most pervasive) is most common in upper trophic
levels (Araújo et al. 2011), and many carnivore species exhibit
high intraspecific variability in diet composition (Dumond et al.2001; Darimont et al. 2009; López-Bao & González-Varo 2011;
Cypher et al. 2014; Davis et al. 2015; Newsome et
al. 2015; Manlick et al. 2019). For carnivore populations with
dominance hierarchies, rank can constrain individual resource access
(Zimen 1976, 1981; Tilson & Hamilton 1984; Gese et al. 1996) and
space use (Gese 2001; Henry et al. 2005; Dorning & Harris 2017;
Kamler et al. 2019), which likely produces predictable
intraspecific variation in the quantity and distance of seeds dispersed.
Below, we describe two carnivore species where recent work on social
behavior indicates that social structure may predict individual seed
dispersal effectiveness.