The key role of the largest extant Neotropical frugivore (Tapirus terrestris) in promoting admixture of plant genotypes across the landscape

Abstract

The historical and contemporary loss of large-bodied frugivores has disrupted many plant-disperser mutualisms, with potentially profound consequences for plants. Although several aspects of seed dispersal by megafrugivores have already been examined, the role of these species in promoting seed-mediated gene flow has remained unexplored. We evaluated the role of the Amazonian tapir (Tapirus terrestris), the largest Neotropical frugivore, in shaping plant genetic structure through seed-mediated gene flow. We used microsatellites to analyze the genetic patterns of Syagrus romanzoffiana seedlings recruited in tapir latrines and around conspecific adult palms, the two sites where seeds and seedlings are most frequently found in this species. While the genetic diversity of seedlings was rather similar in both sites, the kinship structure was substantially weaker in latrines. Most seedlings recruited around adult palms were half-or full-sibs originating from those adults. In contrast, seedlings recruited in latrines came from several (>5, on average) contributing mothers other than the nearest adult (95%) and were mostly non-sibs (72%). Kinship patterns indicated that tapir-mediated dispersal promotes the admixture of genotypes across space. Also, our results suggested that genetic diversity and the number of contributing mothers in latrines increase with the number of fruiting adults visited by tapirs before defecating and with the accumulation of feces over time. We provide evidence of the relevance of tapirs in mobilizing maternal progenies (and genotypes) across the landscape and recruiting clusters of unrelated seedlings. This study suggests a key role for plant-megafrugivore interactions in seed-mediated gene flow and emphasizes the importance of preserving such mutualisms.Abstract in Spanish is available with online material.

Medium and Large-Bodied Mammals of the Private Reserve of Natural Heritage Recanto Das Antas, in Espírito Santo, Brazil

“…Such species are important for plant recruitment and survival, and aid in forest regeneration (Gatti et al 2006, Chapman & Russo 2007, Keuroghlian & Eaton 2008, Tobler et al 2010, Pires & Galetti 2012, Bueno et al 2013, Chalukian et al 2013. Of particular importance is the lowland tapir, a megafrugivore that disperses the seeds of several plant species (Tobler et al 2010, Bueno et al 2013, Giombini et al 2016.…”

The relative contributions of seed and pollen dispersal to gene flow and genetic diversity in seedlings of a tropical palm

“…In addition to the distance seeds move, seed dispersal also determines the effective number of maternal source trees represented at a given seed deposition site, denoted as N em (Grivet, Smouse, & Sork, ). Like seed dispersal distance, N em varies considerably both within and among animal‐dispersed plant systems, with some patches of seedlings originating from multiple maternal source trees and others originating from a single source tree (e.g., Giombini, Bravo, & Tosto, ; Jordano, García, Godoy, & García‐Castaño, ; Karubian, Ottewell, Link, & Di Fiore, ; Ottewell, Browne, Cabrera, Olivo, & Karubian, ; Scofield, Smouse, Karubian, & Sork, ). Because seeds move both male and female gametes, the influence of N em on subsequent patterns of genetic diversity extends beyond female gametes to influence both male and diploid gametic diversity (Grivet et al., ).…”

A predation event by free–ranging dogs on the lowland tapir in the Brazilian Atlantic Forest

“…Because of the aforementioned problems, and considering the minimum population size, we expect that the lowland tapir population in the BRCV are neither demographically nor genetically viable in the long-term (the BRCV is an area of 2,382 ha), and that the presence of free-ranging dogs can act negatively in tandem with other types of impact (e.g., poaching) on the lowland tapir population, as well on the forest diversity (e.g., Gompper, 2013). Their local or functional extinction means loss of seed dispersal agents, especially for plant species that have large fruits and seeds (Bueno et al, 2013), and may also disrupt long-distance dispersal of many plant species (Giombini et al, 2016).…”