DOI: 10.5061/dryad.hk5n4m1
title: Data from: The influence of spatial sampling scales on ant-plant interaction network architecture

description: 1.Despite great interest in metrics to quantify the structure of
 ecological networks, the effects of sampling and scale remain poorly
 understood. In fact, one of the most challenging issues in ecology is how
 to define suitable scales (i.e., temporal or spatial) to accurately
 describe and understand ecological systems. 2.Here, we sampled a series of
 ant‐plant interaction networks in the southern Brazilian Amazon rainforest
 in order to determine whether the spatial sampling scale, from local to
 regional, affects our understanding of the structure of these networks.
 3.To this end, we recorded ant‐plant interactions in adjacent 25 x 30 m
 subplots (local sampling scale) nested within twelve 250 x 30 m plots
 (regional sampling scale). Moreover, we combined adjacent or random
 subplots and plots in order to increase the spatial sampling scales at the
 local and regional levels. We then calculated commonly used binary and
 quantitative network‐level metrics for both sampling scales (i.e., number
 of species and interactions, nestedness, specialization, and modularity),
 all of which encompass a wide array of structural patterns in interaction
 networks. 4.We observed increasing species and interactions across
 sampling scales, and while most network descriptors remained relatively
 constant at the local level, there was more variation at the regional
 scale. Among all metrics, specialization was most constant across
 different spatial sampling scales. Furthermore, we observed that adjacent
 assembly did not generate more variation in network descriptor values
 compared to random assembly. This finding indicates that the spatially
 aggregated distribution of species/individuals and abiotic conditions does
 not affect the organization of these interacting assemblages. 5.Our
 results have a direct impact on our empirical and theoretical
 understanding of the ecological dynamics of species interactions by
 demonstrating that small spatial sampling scales should suffice to record
 some patterns commonly found in ant‐plant interaction networks in a highly
 diverse tropical rainforest.
description: Ant_Plant_interaction_networksAnt-plant interaction networks sampled in December 2010 and January 2011 within a grid system managed by the Brazilian Research Program in Biodiversity (PPBio) (9º48ʹS, 58º15ʹW, between 230 and 274 m a.s.l.). This grid is composed of sampling plots uniformly distributed between two parallel east-west trails 5 km in length, located 1 km apart (5 km2). A sampling plot of 250 x 30 m (7,500 m2) was established every km along each trail (12 plots total). At the local sampling scale, we subdivided each of the 12 plots into ten 25 x 30 m (750 m²) adjacent subplots. Within each interaction matrix, lines represent plant species and columns represent ant species in which elements Aij represent the number of interactions between ant species i and plant species j. The name of each file represents the number of the plot and the spatial class within each plot. For example, in file P1_0_25.txt, "P1" represents "Plot 1" and "0_25" represents that the interactions recorded within this matrix are located between the first 0 and 25 meters, while the file P1_total.txt represents all interactions records in "Plot 1" (from 0 to 250 meters ).