This README.txt file was generated on 2022-09-28 by Qin Li GENERAL INFORMATION 1. Title of Dataset: Data from: Evidence for divergence in phenology over morphology in response to limiting similarity in montane communities of Rhododendron 2. Author/Principal Investigator Information Corresponding Investigator Name: Qin Li ORCID: https://orcid.org/0000-0001-9976-8236 Institution: Field Museum of Natural History, Chicago, USA Email: qli@fieldmuseum.org Co-corresponding Investigator Name: Richard H. Ree ORCID: https://orcid.org/0000-0003-1898-3335 Institution: Field Museum of Natural History, Chicago, USA Email: rree@fieldmuseum.org Date of data collection: 2019-04 -- 2019-06 Geographic location of data collection: the Mt. Gongga region, Sichuan, China Information about funding sources that supported the collection of the data: Field Museum of Natural History SHARING/ACCESS INFORMATION Recommended citation for this dataset: Li et al. (2022) Data from: Evidence for divergence in phenology over morphology in response to limiting similarity in montane communities of Rhododendron. Dryad Dataset. DATA & FILE OVERVIEW 1. Description of dataset These data were generated to investigate co-occurrence of Rhododendron species and divergence along multiple niche axes. In total, 34 Rhododendron species were surveyed across 128 sites in the Mt. Gongga reserve region, population densities were estimated by the variable area transect method, flowering status were recorded across four time periods, and vegetative and floral traits were measured. 2. File List: File 1 Name: Li_et_al_2022_d_trait_avg.csv File 1 Description: geographical locations of 128 surveyed sites; File 2 Name: Li_et_al_2022_a_site_locality.csv File 2 Description: species abundance-by-site matrix; File 3 Name: Li_et_al_2022_b_species_abundance-site_matrix.csv File 3 Description: phenological phases across four time periods (T1-T4) for each species at each site; File 4 Name: Li_et_al_2022_c_flowering_phenology.csv File 4 Description: three vegetative traits and six floral traits of surveyed Rhododendron species. METHODOLOGICAL INFORMATION Between April 25 and June 28, 2019, we censused Rhododendron species in the Gongga Mountain National Nature Reserve (29°10’–30°10’N, 101°10’–102°10’E, an area ca. 1×104 km2) in western Sichuan province, China. In several major valleys surrounding Mt. Gongga, we surveyed 128 sites spaced at intervals of approximately 100 m change in elevation, or distances > 1 km in the absence of elevation change. The sites spanned elevations from 1790--4580 m, with habitats ranging from deciduous and mixed forests to alpine shrublands and meadows. We conducted four censuses, each involving a circuit of visits to all 128 sites, at intervals of 10--17 days over the fieldwork period. We estimated the population densities of Rhododendron species using variable area transects (VAT), an efficient and robust method suitable for dense populations used in previous studies of Rhododendron. For each species at a site, we measured population density once by setting up two transects from different random starting points within the boundaries of their occurrence, each with a fixed width (ω = 1.5 m). The transect length (x) was recorded as the distance to the fourth individual encountered (r = 4). Density was estimated using the formula (nr - 1)/(ω ∑xi). We translated densities to abundances by multiplying by a constant factor of 100 m2. We then constructed a species abundance-by-site matrix and a corresponding binary presence-absence matrix. At each visit, we recorded the phenological phase of each species by visual estimation of the proportion of flowering inflorescences out of the total inflorescences across 10--20 individuals. These values were later normalized by the peak value observed for the species over the duration of the census. To assess functional variation related to growth, stress tolerance, and pollination, we measured three vegetative traits and six floral traits. Plant height and leaf area are indicators of light acquisition ability and correlate to overall plant biomass; specific leaf area (SLA) is a measure of photosynthetic capacity and leaf longevity, commonly used to quantify species response to environmental resources. We collected mature leaves from three individuals per species per site in sealed plastic bags to maintain freshness, and later the same day scanned them on a flatbed scanner (Epson Perfection V19) and dried them in silica gel. We measured leaf area from the scans using ImageJ, and measured leaf mass by an electronic analytical scale after oven-drying at 70°C for 24 hours. Flower size and shape are are pollination-related traits that influence the potential for reproductive interference via heterospecific pollen transfer. We measured corolla tube length and width, corolla lobe length and width, stamen length, and style length on fully-opened flowers of three individuals per species chosen randomly from representative sites (86 in total, ranging 1--10 sites per species, median = 4). DATA-SPECIFIC INFORMATION FOR: Li_et_al_2022_a_site_locality.csv 1. Number of variables: 6 2. Number of cases/rows: 128 3. Variable List: site ID: ordered longitude: decimal degree latitude: decimal degree elevation: m locality information: country, province, city, county, location number of species: number of species per site 4. Missing data codes: none 5. Specialized formats or other abbreviations used: none DATA-SPECIFIC INFORMATION FOR: Li_et_al_2022_b_species_abundance-site_matrix.csv 1. Number of variables: 129 2. Number of cases/rows: 35 3. Variable List: species column plus 128 sites (site_1 - site_128) 4. Missing data codes: none 5. Specialized formats or other abbreviations used: none DATA-SPECIFIC INFORMATION FOR: Li_et_al_2022_c_flowering_phenology.csv 1. Number of variables: 6 2. Number of cases/rows: 393 3. Variable List: site: site id species_name: species T1: time period 1 T2: time period 2 T3: time period 3 T4: time period 4 4. Missing data codes: none 5. Specialized formats or other abbreviations used: none DATA-SPECIFIC INFORMATION FOR: Li_et_al_2022_a_site_locality.csv 1. Number of variables: 10 2. Number of cases/rows: 35 3. Variable List: species leaf_SLA: mm*mm/mg leaf_area: mm*mm height: m corolla_tube_width: mm corolla_tube_length: mm pedal_width: mm pedal_length: mm stamen_length: mm style_length: mm 4. Missing data codes: NA 5. Specialized formats or other abbreviations used: none