DOI: 10.5061/dryad.mh0qs
title: Data from: Between-year changes in community composition shape species' roles in an Arctic plant-pollinator network

description: Inter-annual turnover in community composition can affect the richness and
 functioning of ecological communities. If incoming and outgoing species do
 not interact with the same partners, ecological functions such as
 pollination may be disrupted. Here, we explore the extent to which
 turnover affects species' roles --as defined based on their
 participation in different motifs positions-- in a series of temporally
 replicated plant-pollinator networks from high-Arctic Zackenberg,
 Greenland. We observed substantial turnover in the plant and pollinator
 assemblages, combined with significant variation in species' roles
 between networks. Variation in the roles of plants and pollinators tended
 to increase with the amount of community turnover, although a negative
 interaction between turnover in the plant and pollinator assemblages
 complicated this trend for the roles of pollinators. This suggests that
 increasing turnover in the future will result in changes to the roles of
 plants and likely those of pollinators. These changing roles may in turn
 affect the functioning or stability of this pollination network.
description: Dates_of_first_interactionContains tables listing the date of first observed interactions for each insect (I) and plant (P) in 1996, 1997, 2010, and 2011. Also contains tables identifying which insects (I) and plants (P) had tentatively dated interactions in each year, as well as the best-guess dates associated with these observations.Lists_of_interactionsContains lists of plants and pollinators (i.e., pollination networks) used in our analyses. There were no tentatively dated interactions (n.d.) in 2010 or 2011, so these networks were identical regardless of how these interactions were handled. For 1996 and 1997 networks, the yearly networks were identical in all cases and are therefore only included once (in the "n.d. year only" worksheets). For monthly networks, the "n.d. year only" worksheets describe networks which did not include any tentatively dated interactions, the "n.d. best-guess" worksheets describe networks in which tentatively dated interactions were included in months which included the best-guess date for each such observation (best-guess dates indicated in Dates_of_first_interaction.xls), and the "n.d. range" worksheets describe networks in which tentatively dated interactions were included in months which included any dates between the first and last definitely-dated observations of the same interaction.Network_structureContains lists of motif frequencies by network. The frequencies presented in this file are the raw counts of each motif within each network. For all analyses, these frequencies were normalised by the total number of motifs within the network. Tentatively dated observations were handled as described above. As only the 1996 and 1997 monthly networks varied depending on the handling of these interactions, we present several versions of the network structure for these webs and a single version (contained in sheed monthly - n.d. year only) for the structure of the 2010 and 2011 monthly networks. Motif labels (e.g., 6, 14, and 8472) are as in the motif dictionary associated with the motif detection software mfinder (https://www.weizmann.ac.il/mcb/UriAlon/download/network-motif-software), produced by the Uri Alon lab.Species_roles_monthly_nd_bestguessBecause of the large number of species, we present the roles in each group of webs in separate files. In all cases, position numbers are as in Fig. S7, Appendix S6. Species_roles_monthly_nd_bestguess.xls contains the roles of species in the 1996 and 1997 monthly webs with tentatively dated observations included in webs containing the best-guess date. These are the roles used to generate the results presented in the main text. As there were no tentatively dated observations in 2010 or 2011, all roles in these webs were the same for all methods of handling tentatively dated observations. We therefore include them in only the file Species_roles_monthly_nd_yearonly.xls.Species_roles_monthly_nd_rangeBecause of the large number of species, we present the roles in each group of webs in separate files. In all cases, position numbers are as in Fig. S7, Appendix S6. Species_roles_monthly_nd_range.xls contains the roles of species in the 1996 and 1997 monthly webs with tentatively dated observations included in webs containing any dates within the range for which the same interaction was definitely observed. As there were no tentatively dated observations in 2010 or 2011, all roles in these webs were the same for all methods of handling tentatively dated observations. We therefore include them in only the file Species_roles_monthly_nd_yearonly.xls.Species_roles_monthly_nd_yearonlyBecause of the large number of species, we present the roles in each group of webs in separate files. In all cases, position numbers are as in Fig. S7, Appendix S6. Species_roles_monthly_nd_yearonly.xls contains the roles of species in the monthly webs, with tentatively dated observations excluded. This is the only monthly roles file containing species roles in 2010 or 2011 as there were no tentatively-dated observations in either year.Species_roles_yearlyBecause of the large number of species, we present the roles in each group of webs in separate files. In all cases, position numbers are as in Fig. S7, Appendix S6. Species_roles_yearly.xls contains the roles of species in the yearly webs. All tentatively-dated observations were associated with a definite year; therefore there is only one version of species roles in yearly networks.READMEOverview of all files, including a summary of which Species_roles files are associated with which network and method of handling tentatively-dated observations.