Mistletoes on lianas: Seed dispersal highways or drought safe havens? Evidence from South American temperate rainforests

Abstract

.Lianas are woody plants that depend on other plants for structural support to reach the forest canopy and obtain the light necessary for photosynthesis (Blick & Burns, 2011; Schnitzer et al., 2005; Schnitzer & Bongers, 2002). Such dependence can generate both competitive interactions for resources with supporting plants as well as facilitation from pollination and seed dispersal by animals that visit the lianas in search of nectar and fleshy fruits (Kilgore et al., 2010). In turn, lianas can provide habitat for reproduction, protection from predators, and routes for connection and mobility between forest strata (Adams et al., 2017; Odell et al., 2019; Schnitzer, 2018). In the latter case, using lianas as travel routes for arboreal animals may influence forest composition because many plants with fleshy fruits depend on biotic vectors that use lianas as movement routes during seed dispersal (Lambert et al., 2006). In tropical rainforests, seeds of Rafflesia–liana-specific parasitic plants (Tetrastigma spp.) are dispersed by squirrels and tree shrews, who use them as movement routes that constitute forest highways (Emmons et al., 1991; Pelser et al., 2016; Renjana et al., 2022).