The effects of Metarhizium exposure, gland closure, and ant
species on brood survival and the effects of gland closure and
ant species on the appearance of foreign fungi on nest material
were analyzed using Cox proportional hazards regression
models. Colony of origin and cohort (in experiment 1) were
included in the models to account for the structured nature of
the data. Pairwise Kaplan–Meier tests were used to test
for pairwise differences between treatment groups. The
effects of blockage on the duration of behavioral interactions
of nurse ant and brood were examined using
Mann–Whitney U tests, and the survival of the nurses
was analyzed using Cox proportional hazards regression
models. The proportions of brood sporulating with fungi
were examined with χ2 tests, and the proportions of
nest material sporulating with fungi were analyzed with
Fisher’s exact tests.