DOI: 10.5061/dryad.p52kg
title: Data from: Changing light conditions in pine rockland habitats affect the intensity and outcome of ant–plant interactions

description: Extrafloral nectar (EFN) mediates food-for-protection mutualisms between
 plants and ants. Such mutualisms exist within a complex web of biotic
 interactions, and in a framework provided by the abiotic environment. Both
 biotic and abiotic factors, therefore, affect the outcome of ant–plant
 interactions. We conducted an experiment to determine the effects of ant
 activity, and light intensity, on herbivory rates, growth, and
 reproductive fitness in Senna mexicana var. chapmanii, a perennial legume
 native to pine rockland habitats of south Florida. Forty plants were
 divided among four treatments in a factorial experimental design with two
 independent variables: ant activity and light intensity. Plants were
 divided equally between sunny and shady habitats, and ants were excluded
 from half of the plants in each habitat type. The presence of ants
 significantly reduced herbivory rates in S. chapmanii. In shaded habitats,
 the presence of ants had no effect on plant reproductive fitness, however,
 in sunny habitats plants with ants produced significantly more seeds over
 the duration of the 1-yr study. Ants represent an important biotic defense
 against herbivores in S. chapmanii; however, their effects on plant
 fitness are dependent on light conditions. Pine rockland habitats in south
 Florida have been widely destroyed or mismanaged. In fragments that
 remain, suppression of fire has led to increased canopy closure and
 shading of the understory. These changes will likely negatively impact
 plants that rely on ants for defense. We highlight the importance of
 conservation efforts to preserve the pine rocklands and the fire regimes
 on which they rely.
description: Data file for Dryad
 repositorySheet 1 of the data file
 contains data describing plant growth rates. Column A identifies the
 individual plant. Column B show the light treatment (0=shade, 1=sun).
 Column C indicates ant treatment (0=ants present, 1-ants absent. Columns D
 through X are measurements of plant growth rate as an estimate of
 increased biomass over each 2 week period. Sheet 2 of the data file
 contains data describing herbivory rates. Column A identifies the
 individual plant. Column B show the light treatment (0=shade, 1=sun).
 Column C indicates ant treatment (0=ants present, 1-ants absent. Columns D
 through X are measurements of plant herbivory rate as an estimate of %
 leaf area removal. Sheet 3 of the data file contains data describing plant
 size. Column A identifies the individual plant. Column B show the light
 treatment (0=shade, 1=sun). Column C indicates ant treatment (0=ants
 present, 1-ants absent. Columns D through AB are measurements of plant
 size, taken as the total number of growing stems. Sheet 4 of the data file
 contains data describing extrafloral nectar production. Column A
 identifies the individual plant. Column B show the light treatment
 (0=shade, 1=sun). Column C indicates ant treatment (0=ants present, 1-ants
 absent. Columns D through I are bi-monthly measurements of extrafloral
 nectar production, expressed as total sugar production from 5 leaves on
 each plant. Sheet 5 of the data file contains data from insect surveys
 conducted throughout the year long study. Column A shows the date that
 surveys were conducted. Column B identifies the individual plant. Column C
 shows the light treatment (0=shade, 1=sun). Column D indicates ant
 treatment (0=ants present, 1-ants absent. Column E indicates whether the
 survey was conducted during the day or at night (0=day, 1=night). Columns
 F through AY are different insects and they presence and abundance are
 indicated for each survey. Sheet 6 of the data file contains data
 describing plant reproductive fitness. Column A shows the date that data
 were collected. Column B identifies the individual plant. Column C shows
 the light treatment (0=shade, 1=sun). Column D indicates ant treatment
 (0=ants present, 1-ants absent. Columns E, F, G, and H indicate numbers of
 flowers, fruit set, mature fruit, and seeds
 respectively.