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Harvard Forest Data Archive


Assessing Plant Phenological Character Displacement Across the Eastern United States Since 1895

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  • Lead: Daniel Park, Ian Breckheimer, Charles Davis
  • Investigators: Aaron Ellison, Goia Lyra, Junxi Xie
  • Contact: Information Manager
  • Start date: 1895
  • End date: 2018
  • Status: ongoing
  • Location: Eastern United States
  • Latitude: +25.51 to +46.66 degrees
  • Longitude: -87.38 to -67.63 degrees
  • Elevation: 4.31 to 1101.02 meter
  • Datum: WGS84
  • Taxa: Asimina angustifolia, Anemone canadensis, Anemone cylindrica, Anemone hepatica, Anemone quinquefolia, Anemone virginiana, Arisaema dracontium, Arisaema triphyllum, Aristolochia macrophylla, Aristolochia serpentaria, Asimina parviflora, Asimina triloba, Calopogon pallidus, Calopogon tuberosus, Chamaecrista fasciculata, Chamaecrista nictitans, Clematis crispa, Clematis occidentalis, Clematis reticulata, Clematis viorna, Clematis virginiana, Clintonia borealis, Clintonia umbellulata, Dicentra canadensis, Dicentra cucullaria, Erythronium americanum, Erythronium umbilicatum, Halesia carolina, Halesia diptera, Halesia tetraptera, Helenium amarum, Helenium autumnale, Helenium flexuosum, Helenium pinnatifidum, Helenium vernale, Hexastylis arifolia, Hexastylis virginica, Hibiscus aculeatus, Hibiscus laevis, Hibiscus moscheutos, Hibiscus syriacus, Hibiscus trionum, Iris cristata, Iris hexagona, Iris prismatica, Iris pseudacorus, Iris verna, Iris versicolor, Iris virginica, Lilium canadense, Lilium catesbaei, Lilium philadelphicum, Lilium superbum, Mimosa microphylla, Mimosa quadrivalvis, Mimosa strigillosa, Opuntia humifusa, Opuntia megacantha, Opuntia pusilla, Opuntia stricta, Passiflora incarnata, Passiflora lutea, Passiflora suberosa, Phlox amoena, Phlox carolina, Phlox divaricata, Phlox drummondii, Phlox glaberrima, Phlox nivalis, Phlox paniculata, Phlox pilosa, Phlox stolonifera, Phlox subulata, Physalis angulata, Physalis angustifolia, Physalis heterophylla, Physalis longifolia, Physalis pubescens, Physalis walteri, Rosa blanda, Rosa carolina, Rosa nitida, Rosa palustris, Rosa virginiana, Rudbeckia fulgida, Rudbeckia hirta, Rudbeckia laciniata, Rudbeckia triloba, Sabatia angularis, Sabatia bartramii, Sabatia brevifolia, Sabatia calycina, Sabatia campanulata, Sabatia difformis, Sabatia dodecandra, Sabatia grandiflora, Sabatia stellaris, Sarracenia flava, Sarracenia minor, Sarracenia psittacina, Sarracenia purpurea, Styrax americanus, Styrax grandifolius, Trillium catesbaei, Trillium cernuum, Trillium cuneatum, Trillium erectum, Trillium grandiflorum, Trillium maculatum, Trillium rugelii, Trillium undulatum, Trillium vaseyi, Uvularia grandiflora, Uvularia perfoliata, Uvularia puberula, Uvularia sessilifolia
  • Release date: 2023
  • Language: English
  • EML file: knb-lter-hfr.335.5
  • DOI: digital object identifier
  • EDI: data package
  • DataONE: data package
  • Related links:
  • Study type: historical
  • Research topic: biodiversity studies; conservation and management; ecological informatics and modelling; regional studies
  • LTER core area: population studies
  • Keywords: climate change, flowering, phenology, plant species, reproduction, temperature
  • Abstract:

    Reproductive character displacement has long been hypothesized to be a key determinant of speciation and co-existence in flowering plants. A central tenet of this hypothesis is that reproductive traits of close relatives growing in sympatry diverge more than they do where close relatives do not grow together. However, this idea remains untested across taxa and at large spatial scales. Here, we use data collected from tens of thousands of herbarium specimens to examine evidence for character displacement in flowering time for 91 closely-related pairs of animal-pollinated angiosperm species in the eastern USA. We see no evidence for overall phenological divergence in sympatry across regions, clades, or life histories. Rather our results indicate widespread convergence of flowering times in sympatry for species pairs that generally tend to flower close in time. We also find that climate change could alter the nature of these convergent flowering events by shifting them further apart in a majority species pair comparisons. Specifically, congeneric species in New England and the Atlantic Coastal Plain are projected to flower 2–4 days further apart, on average, by the mid-21st century as warming temperatures drive species-specific phenological shifts within genera. This may have significant consequences for species interactions and gene flow, especially if current sympatric convergence in flowering times has resulted from facilitative interactions between species.

  • Methods:

    The web tool CrowdCurio was used to crowdsource phenological data from more than 40,000 herbarium specimens representing 116 flowering plant species across the eastern United States.

    Data file contains the R code (four scripts, to be run in sequence) and associated input files (.csv, .gpkg, and .tre) for replicating the analyses in the paper.

  • Organization: Harvard Forest. 324 North Main Street, Petersham, MA 01366, USA. Phone (978) 724-3302. Fax (978) 724-3595.

  • Project: The Harvard Forest Long-Term Ecological Research (LTER) program examines ecological dynamics in the New England region resulting from natural disturbances, environmental change, and human impacts. (ROR).

  • Funding: National Science Foundation LTER grants: DEB-8811764, DEB-9411975, DEB-0080592, DEB-0620443, DEB-1237491, DEB-1832210.

  • Use: This dataset is released to the public under Creative Commons CC0 1.0 (No Rights Reserved). Please keep the dataset creators informed of any plans to use the dataset. Consultation with the original investigators is strongly encouraged. Publications and data products that make use of the dataset should include proper acknowledgement.

  • License: Creative Commons Zero v1.0 Universal (CC0-1.0)

  • Citation: Park D, Breckheimer I, Davis C. 2023. Assessing Plant Phenological Character Displacement Across the Eastern United States Since 1895. Harvard Forest Data Archive: HF335 (v.5). Environmental Data Initiative:

Detailed Metadata

hf335-01: crowdsourced phenological data

  1. coreid: unique ID of specimen record
  2. species: binomial species name
  3. username: unique crowdsourcer ID
  4. bud: bud counts (unit: number / missing value: NA)
  5. flower: flower counts (unit: number / missing value: NA)
  6. fruit: fruit counts (unit: number / missing value: NA)
  7. family: family name
  8. genus: genus name
  9. county: US county where specimen was collected
  10. state: US state where specimen was collected
  11. longitude: county centroid coordinates in decimal degrees (unit: degree / missing value: NA)
  12. latitude: county centroid coordinates in decimal degrees (unit: degree / missing value: NA)
  13. date: date of collection
  14. year: collection year
  15. month: collection month
  16. day: collection day
  17. goodqualityaccess_url: medium quality specimen image
  18. access_url: high quality specimen image

hf335-02: phenological displacement R code

  • Compression: zip
  • Format: csv, GeoPackage, R script
  • Type: document, script, vector GIS