DOI: 10.5061/dryad.hqbzkh1tn
title: Data from: Temporal biotic homogenisation patterns due to urbanisation are taxon-dependent

description: Aim: Accelerated urbanisation poses a major threat to global biodiversity.
 However, few studies have explored patterns of temporal biotic
 homogenisation due to urbanisation across multiple taxa. Location: Tokyo,
 Japan Methods: We examined the temporal changes in species richness and
 composition in 15 remnant green spaces across the Tokyo metropolitan area,
 Japan, focusing on native species of three taxa (plants: 15 sites, birds:
 7 sites, and butterflies: 7 sites). First, we compared gamma diversity and
 species composition (dispersion and itself) between two surveys at a
 regional scale included all study sites. Furthermore, we assessed temporal
 change in alpha diversity (species richness over time) and temporal beta
 diversity (changes in species composition over time) at each green space.
 We also clarified the relationships between those indices and
 environmental variables. To determine the species more impacted by
 urbanisation, we examined the relationship between the rate of species
 loss and their traits related to dispersal and adaptation. Results: Gamma
 diversity decreased from the first to the second survey regardless of
 taxa. However, the pattern of temporal diversity changes due to
 urbanisation varied among taxa. For plants, temporal changes in alpha
 diversity decreased with the number of years between surveys. For birds,
 temporal beta diversity increased with the number of years between
 surveys. For butterflies, the dispersion of species composition at the
 regional scale decreased slightly from the first and the second survey.
 Annual herb and water-dispersal plant species, as well as bird species
 with higher diet specialization, were more prone to lose due to
 urbanisation. Main conclusions: Our findings demonstrate that patterns of
 temporal biotic homogenisation due to urbanisation vary among taxa.
 Therefore, enhancing species diversity within each green space and
 promoting species composition differences among green spaces is necessary
 to maximise multi-taxa diversity in urban areas.
description: # Temporal biotic homogenisation patterns due to urbanisation are
 taxon-dependent
 [https://doi.org/10.5061/dryad.hqbzkh1tn](https://doi.org/10.5061/dryad.hqbzkh1tn) ## Description of the data and file structure This data contains the raw data for plant (*df_plant_output.csv*), bird (*df_bird_output.csv*), and butterfly (*df_butterfly_output.csv*) communities of past and present at each green space, and environments for each green space (*df_env_output.csv*), and script for analysis (analysis.html). Those not found in the database are indicated as NA in the trait values for each taxon. ##### Discriptions: raw data for plant commuties (*df_plant_output.csv*) * site: study site name * time: survey time (past or present) * value: Whether it was discovered at the time of the survey (all value are 1) * exotic: Native species or Exotic species * sciname: scientific species name * growth: growth form at each species (tree, perennial, annual, NA) * disper: dispersal mode (grabity, wind, animal, water, NA) raw data for bird commuties (*df_bird_output.csv*) * site: study site name * time: survey time (past or present) * sciname: scientific species name * value: Whether it was discovered at the time of the survey (all value are 1) * exotic: Native species or Exotic species * Beak: beak lenght for each bird species (centimeter) * HWI: hand-wing index for each bird species (ratio) * Mass: body mass for each bird species (gram) * spec_diet: specilization of diet for bird species (bigger values indicate a smaller feeding range) (unit less) * spec_nest: specilization of nest place for bird species (bigger values indicate a limited nest place) (unit less) raw data for butterfly commuties (*df_butterfly_output.csv)* * site: study site name * time: survey time (past or present) * sciname: scientific species name * value: Whether it was discovered at the time of the survey (all value are 1) * exotic: Native species or Exotic species * FlightDuration: number of months per year that can be inhabited (month) * WS: wing span for each butterfly species (cm) * hostplant: number of host plant species richness raw data for environmental variables (*df_env_output.csv)* * site: study site name * year: number of years between surveys (past and present) * area: size of green space (m2) * green_rate: green cover around study site within 1km (ratio) ## Code/software All statistical analysis code in R (analysis.html) * This is code for all analysis (Fig. 1-5)