DOI: 10.5061/dryad.k0p2ngfkb
title: Evidence for increased animal pollination during the Paleocene-Eocene Thermal Maximum

description: The Paleocene-Eocene Thermal Maximum (PETM) was the largest early Cenozoic
 hyperthermal event, one of a series of carbon cycle and climate
 perturbations marked by massive releases of carbon into the atmosphere and
 spikes in global temperature. Previous studies have documented major
 changes in the composition of terrestrial plant and animal communities
 during the PETM, as well as changes in arthropod herbivory. Here we
 examine possible changes in pollination mode during the PETM in the
 Bighorn Basin, Wyoming, USA, as inferred from three lines of evidence: (1)
 the prevalence of fossil pollen preserved as clumps, (2) the pollination
 mode of nearest living relatives (NLR), and (3) angiosperm pollen
 morphological diversity. These suggest animal pollination became more
 common and wind pollination less common during the PETM. The decrease in
 wind pollination during the PETM reflects the basin-scale extirpation of
 wind-pollinated lineages and their replacement by dominantly
 animal-pollinated lineages due to rapid warming and drying. The hotter and
 more seasonally dry climates not only facilitated the northward range
 shift of plant taxa, but also their insect and/or vertebrate pollinators.
 The dramatic floral changes during the PETM in the Bighorn Basin may also
 have changed available resources for insect and/or vertebrate pollinators.
description: # Evidence for increased animal pollination during the Paleocene-Eocene
 Thermal Maximum Dataset DOI:
 [10.5061/dryad.k0p2ngfkb](10.5061/dryad.k0p2ngfkb) ## Description of the
 data and file structure **Summary of dataset contents:** **Table S1** –
 Sample information for each locality. This includes: | **VARIABLE** |
 **DEFINTION** | **UNIT** | | :------------------------------ |
 :------------------------------------------------------------------------------------------------------------------------------- | :---------------- | | Locality | Name of sample site | NA | | Equivalent localities | Equivalent name of sample site | NA | | Composite stratigraphic section | Stratigraphic section the sample site fits within | NA | | m level | Stratigraphic level of sample within each stratigraphic section | meters | | Lower tie point | Lower tie point of known geological age | NA | | Upper tie point | Upper tie point of known geological age | NA | | Age (Ma) | Age of sample site | Millions of years | | CIE phase | Age of sample site in relation to the carbon isotope excursion (CIE) associated with the Paleocene-Eocene Thermal Maximum (PETM) | NA | | Latitude | Latitude | Decimal degrees | | Longitude | Longitude | Decimal degrees | | Depositional environment | Depositional environment of sample site | NA | | Section reference | Original publication of composite stratigraphic section | NA | | %TOC | Percent total organic carbon | NA | | %Clay | Percent clay | NA | | %Silt | Percent silt | NA | | %Sand | Percent sand | NA |   **Table S2** - Pollen size measurements. | **VARIABLE** | **DEFINTION** | **UNIT** | | :-------------- | :----------------------------------------- | :------- | | Pollen taxa | Name of spore or pollen species | NA | | Size #1 | Measured size of one individual | Microns | | Size #2 | Measured size of one individual | Microns | | Size #3 | Measured size of one individual | Microns | | Size #4 | Measured size of one individual | Microns | | Size #5 | Measured size of one individual | Microns | | Median | Median size of individuals | Microns | | Std deviation | Standard deviation of measured sizes | Microns | | Co of variation | Coefficient of variation of measured sizes | Microns |   **Table S3** - Summarized angiosperm morphology data. | **VARIABLE** | **DEFINTION** | **UNIT** | | :------------------------ | :---------------------------------------------------------------- | :----------------------------- | | Taxa | Name of spore or pollen species | NA | | Reference | Reference/s for description of individual spore or pollen species | NA | | Apertures | Pollen aperture | Morphological character score | | Exine stratification | Exine of pollen | Morphological character score | | Shape | Shape of pollen | Morphological character score | | Dispersal unit | Dispersal unit of pollen | Morphological character score | | Surface ornamentation one | Surface ornamentation of pollen | Morphological character score | | Surface ornamentation two | Second surface ornamentation of pollen | Morphological character score  |   **Table S4** -Pollen cluster abundance and diversity. | **VARIABLE** | **DEFINTION** | **UNIT** | | :--------------------------- | :----------------------------------------------------- | :---------------- | | Site | Name of sample site | NA | | Pollen cluster number | Number of pollen clusters per site | NA | | Cluster species diversity | Number of species found in clusters | NA | | Depositional environment | Depositional environment of sample site | NA | | Taxa present as clusters | Species of pollen identified as clusters | NA | | Pollen concentration | Concentration of pollen grains in each sample site | Centimeters cubed | | Sediment volume | Volume of sediment analyzed per sample site | Centimeters cubed | | Clusters per cm3 of sediment | Clusters of pollen recovered from each cm3 of sediment | Centimeters cubed | **Table S5** - Palynofloral affinities. This includes the species, botanical affinity and reference. | **VARIABLE** | **DEFINTION** | **UNIT** | | :----------- | :------------------------------------------------------------------------- | :------- | | Species | Individual fossil spore and pollen species | NA | | Affinity | Affinity of species at the Family and/or (Genus) level | NA | | Reference | Reference/s for interpreted affinity of individual spore or pollen species | NA |   Table S6 - Pollination mode of nearest living relatives (NLRs). This includes the NLRs, botanical affinities and reference.   | **VARIABLE** | **DEFINTION** | **UNIT** | | :--------------- | :------------------------------------------------------------------------------------------------------------------------------- | :------- | | Species | Individual fossil spore and pollen species | NA | | Affinity | Affinity of species at the Family and/or (Genus) level | NA | | Pollination mode | Pollination mode of each species. Mixed = insect & wind or insect, mammal and wind whereas biotic = insect and mammal or insect. | NA | | Reference | Reference for interpreted pollination mode of individual pollen species | NA |   **Table S7** - Summarized occurrence data (presence/absence) derived from Korasidis and Wing 2023. | **VARIABLE** | **DEFINTION** | **UNIT** | | :----------- | :------------------------------------------------------------------------------------ | :------- | | Taxa | Individual fossil pollen species | NA | | Pre-CIE | Species present in rocks of pre carbon isotope excursion (CIE) age | y/n | | CIE body | Species present in rocks formed during the body of the carbon isotope excursion (CIE) | y/n | | Post-CIE | Species present in rocks of post carbon isotope excursion (CIE) age | y/n |   Table S8 - Contingency table of median pollen size data.   | **VARIABLE** | **DEFINTION** | **UNIT** | | :----------- | :------------------------------------------------------------ | :------- | | Age | Age of samples relative to the carbon isotope excursion (CIE) | NA | | &lt;20 µm | Number of species &lt;20 µm in size | NA | | 20-40µm | Number of species between 20-40µm in size | NA | | &gt; 40µm | Number of species &gt; 40µm in size | NA | **Text S1.** R code used to calculate the Hamming Distance.  **Text S2.** References cited in the Supporting Information (Tables S1-8).  ## Code/software R code available in Text S1.  ## Access information NA