Data from "Are Introduced Species Better Dispersers Than Native Species? A Global Comparative Study of Seed Dispersal Distance."

We performed a search on ISI Web of Knowledge for papers published between 1906 and 2010 with information on seed dispersal distance of introduced plants. The search terms we used were ‘seed’ + ‘dispersal distance’ or ‘seed dispersal’ + ‘distance’, and ‘dispersal kernel’, ‘dispersal curve’ or ‘seed shadow’ restricted by the terms ‘weed$’, ‘introduced’, ‘invasive’,’non-invasive’, ‘naturaliz*’, ‘alien’, ‘non- native’, and ‘noxious’. We also searched for relevant papers in the reference lists of focal papers. We only included papers that presented observational or experimental information on the mean and/or maximum dispersal distance of plant species under field conditions. This included studies that used seed traps, tracked individual seeds, marked and recaptured seeds and estimated dispersal distances based on tracking vectors and calculating gut or fur retention times. We excluded all studies that estimated seed dispersal distances from seed size, including mass and shape, or dispersal syndrome because these variables were included in the analyses. We excluded studies that used artificial or unrealistic conditions, such as wind tunnels, artificial fur or artificial seeds. Studies that calculated seed dispersal distance from buoyancy tests or terminal velocity tests were also excluded. Studies that estimated dispersal distances based on spatial population mathematical models and inverse modeling of seedling distance to nearest adult or mother plant were excluded because they are influenced by post-dispersal processes such as germination success, seed predation and seedling predation. Studies with less than ten replicates for a given species for either mean or maximum dispersal distance were also excluded. When observational and experimental information were both included in the study, we preferentially used observational information. Information on species’ status (native/introduced) was extracted from the same papers as dispersal distance data. Information on dispersal distances were extracted from three sources (in diminishing order of preference): 1) tables, 2) main text or 3) graphs using DatathiefIII [41]. Maximum and mean dispersal distances were used instead of percentiles since these were the most common measures throughout the literature The database structure is as follows and is decribed by columns: Species range: whether the species is introduced or native, this database only contains introduced species, therefore all rows should be labeled as "introduced" Species: Genus_species binomial dispersal mechanims: This information was extracted from the same study as dispersal distance data, the categories are: anemochory, ballochory, barochory, endozochory, epizochory, harvest (human dispersal), hydrochory, hygroscopic, myrmechory, tumbleweed Mean.dispersal.distance: Average of the mean dispersal distance register per species per study. No mean dispersal distance was included if Maximum.dispersal.distance: Maximum dispersal distance register per species per study. No maximum dispersal distance was included if Growth.form: Woody or non-woody. This information was extracted from the same study as dispersal distance data or alternatively from floras. Biome: This information was extracted from the same study as dispersal distance data, the categories are: grassland, shrubland, temperateforest, tropical forest, woodland and other N-fixers: whether the plants are N-fixwers or not. This information was extracted from floras Family: family taxonomic rank that the species belong to. This information was extracted from The Angiosperm phylogeny website, 2003 (Steven, 2001 onwards) and The Plant List (2010) Order: order taxonomic rank that the species belong to. This information was extracted from The Angiosperm phylogeny website, 2003 (Steven, 2001 onwards) and The Plant List (2010) Clade: clade taxonomic rank that the species belong to. This information was extracted from The Angiosperm phylogeny website, 2003 (Steven, 2001 onwards) Reference: Main reference where the dispersal distance data were extracted from Secondary reference: Referecence where dispersal distance data were extracted from that was found in the main references References: Stevens, P.F. (2001 onwards) Angiosperm Phylogeny Website. Available:http://www.mobot.org/MOBOT/research/APweb/. Accessed 2012 April. The Plant List (2010) Available at http://www.theplantlist.org/. Please contact [e-mail] if you have any questions or spot any error in the database.