The turnover of plant-frugivore interactions along plant range expansion: consequences for natural colonisation processes

Plant-animal mutualisms such as seed dispersal are key interactions for sustaining plant range shifts. Whether the organisation of interactions with seed dispersers is reconfigured along the expansion landscape template, and its effects accelerating or slowing colonisation, remain elusive. Here we analyse plant-frugivore interactions in a scenario of rapid population expansion of a Mediterranean juniper. We combined complex network analyses with intensive field surveys, sampling interactions between individual plants and frugivores by DNA-Barcoding and phototrapping over two seasons. We assess the role of intrinsic and extrinsic intraspecific variability in shaping interactions and we estimate the contribution of individual plants to seed rain. The whole interaction network was highly structured, with a distinct set of modules including individual plants and frugivore species arranged concordantly along the expansion gradient. The modular configuration found was partially shaped by indi..., Study area
The study was carried out in the Doñana National Par (Spain). We selected three 1-ha stands along the juniper natural regeneration gradient. In the three stands, all individual junipers were identified and geo-referenced. The mature stand, named \"Sabinar del Marqués\" (MAR), has the highest juniper density and is an old forest with a high dominance of J. phoenicea. Advancing towards the colonisation front, the second stand called \"Sabinar del Ojillo\" (OJI) represents a stage of intermediate maturity with a lower juniper density. The last stand is named \"Sabinar de Colonización\" (COL) and represents a colonisation front or expansion area. We established five evenly distributed subplots in each stand. We used these subplots to randomly select 35 focal individual plants in each stand (N = 105). Fieldwork was carried out during two consecutive fruiting seasons (October 2018–May 2019 and September 2019–May 2020).
Plant-animal interactions survey
Phototrapping
Eight camera traps wer..., The only software needed to open the datasets and replicate the analyses is Rstudio.Â