Evaluating the factors that promote invasive ant abundance is critical to assess their ecological impact and inform their management. Many invasive ant species show reduced nestmate recognition and an absence of boundaries between unrelated nests, which allow populations to achieve greater densities due to reduced intraspecific competition. We examined nestmate discrimination and colony boundaries in introduced populations of the red imported fire ant (Solenopsis invicta; hereafter, fire ant). Fire ants occur in two social forms: monogyne (colonies with a single egg-laying queen) and polygyne (colonies with multiple egg-laying queens). In contrast with monogyne nests, polygyne nests are thought to be interconnected due to the reduced antagonism between non-nestmate polygyne workers, perhaps because polygyne workers habituate the colony to an odor unique to Gp-9^b-carrying adults. However, colony boundaries and nestmate discrimination are poorly documented, particularly for worker-brood interactions. To delimit boundaries between field colonies, we correlated the exchange of a ¹⁵N-glycine tracer dissolved in a sucrose solution with social form. We also evaluated nestmate discrimination between polygyne workers and larvae in the laboratory. Counter to our expectations, polygyne colonies behaved identically to monogyne colonies, suggesting both social forms maintain strict colony boundaries. Polygyne workers also preferentially fed larval nestmates and may have selectively cannibalized non-nestmates. The levels of relatedness among workers in polygyne colonies was higher than those previously reported in North America (mean ±SE: 0.269 ± 0.037). Our study highlights the importance of combining genetic analyses with direct quantification of resource exchange to better understand the factors influencing ant invasions.

Descriptions for "FireAnt_Data_revised.xlsx" FILE (also included in the README.txt)

"null" has been included in all empty cells.

Sheet 1 - "Raw_Isotope_Data"
This includes all of the raw isotope data, lat long coordinates of each mound, and distance to the treated mound in meters (0 if the mound was the treated mound). 
"Site" corresponds to one of six total sites (A, Br, O, C, T, and T2 - locations of each site is described in the original paper). 
"Cluster" refers to the cluster of mounds that were treated within each site. 
"Mound" refers to the mounds within each cluster (0 corresponds with the mound that was treated with the isotope tracer). 
"Time" corresponds to when the treated mounds were given the isotope tracer (0 refers to pre-treatment, 1 refers to post-treatment). 
"d15N" is the nitrogen-15 isotope values of ants from each mound. 
"d13C" is the carbon-13 isotope values of ants from each mound. 
"percN" is the percent nitrogen of ants from each mound. 
"percC" is the percent carbon of ants from each mound. 
"lat" and "long" correspond to latitudinal and longitudinal GPS coordinates of each mound. 
"Distance" is the distance in meters of the mound from the treated mound within each cluster.

Sheets 2-4 - "Genepop_format", "Genotypes_S.invicta", "Sampling_summary"
Raw microsatellite results for each worker within each mound (eight workers per mound whenever possible). 
"Genepop_format" is the raw file that can be used in Genepop. 
The "Individual" column in "Genotypes_S.invicta" corresponds to a unique ID for each worker & mound (explained in the "Sampling_summary"). 
"Sol49_1", "Sol49_2", "Sol42_1", "Sol42_2", "Sol55_1", "Sol55_2", "Sol20_1", "Sol20_2", "Sol11_1", "Sol11_2" correspond to the microsatellites used (as described in the original paper). 
"GP-9" corresponds to the Gp-9 status of the workers (polygyne or monogyne).

Sheet 5 - "Relatedness_Papers"
Includes all of the reviewed papers appearing in Figure 3 of the manuscript. Standard error of all relatedness values are included whenever these results were given in the original study. 
"Study" refers to the specific study where the values were obtained. 
"Reference_in_plot" refers to the number included in Figure 3 of the manuscript. 
"Social.form" refers to the social form of the fire ants studied.
"Location" is where the ants were collected in each study.
"Relatedness" is the relatedness coefficient extracted from the study (either from tables or from plots using ImageJ).
"SE" is standard error of the relatedness coefficients whenever these results were given in the original study.
"Measure" refers to what type of relatedness coefficient was given (i.e., Queller relatedness coefficient or Regression coefficients of relatedness).
"Sig.greater.0" is whether the relatedness coefficient was found to be significantly greater than 0 in the study.
"Notes" are additional notes from each study.

Sheet 6-7 - "LabExp_Larvae_Remaining", "LabExp_Larvae_Fed"
Results from laboratory experiments testing nestmate recognition in fire ants, as described in the manuscript. 
"Colony" refers to the natal colony identity of the workers.
Data includes the number of larvae remaining that were from a different colony (non-nestmates) and from the same colony (nestmates), and the percent of larvae fed that were from a different colony (non-nestmates) and from the same colony (nestmates).