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Table 1 Summary of generalized linear mixed model (GLMM), generalized linear model (GLM) or cumulative link mixed models (CLMM) results for each response variable for analyses of 1) colony observations, 2) the queen transfer experiment, and 3) aggression tests. ‘x’ represents the interaction term  * p < 0.05, ** p < 0.01, *** p<0.001

From: Origin, behaviour, and genetics of reproductive workers in an invasive ant

Response and explanatory variables df χ2 or LRstat p
1. Male production, GLMM binomial, n = 233 colonies
Whether the colony ever had a queen 1 2.28 0.13
Maximum number of workers 1 35.35 < 0.0001***
Days in captivity 1 3.17 0.08
Whether the colony ever had a queen x max. Number of workers 1 7.58 < 0.0059**
Whether the colony ever had a queen x days in captivity 1 3.04 0.08
2. Proportion of normal workers until day 60, GLMM binomial, n = 100 observations and 10 colonies
Colony status (queenright or queenless) 1 1.80 0.18
Time (since the beginning of the experiment) 4 15.57 0.0037**
Colony status x Time 4 14.49 0.0059**
Proportion of normal workers until day 120, GLMM binomial, n = 54 observations and 3 colonies
Colony status (queenright or queenless) 1 0.0001 0.99
Time (since the beginning of the experiment) 8 47.26 < 0.0001***
Colony status x Time 8 37.92 < 0.0001***
3. Maximal aggression score, CLMM, n = 70
Colony status 1 5.66 0.0173*
Worker type 1 6.65 0.0099**
Colony status x Worker type 1 1.30 0.25
Survival of all three A. gracilipes workers, GLMM negative binomial, n = 70
Colony status 1 2.45 0.12
Worker type 1 0.33 0.57
Colony status x Worker type 1 1.83 0.18
Survival of the O. smaragdina worker, GLMM binomial, n = 70
Colony status 1 14.45 < 0.0001***
Worker type 1 1.53 0.22
Colony status x Worker type 1 6.19 < 0.0129*
Species initiating the fight, GLM binomial, n = 51
Colony status 1 4.12 0.0423*
Worker type 1 5.25 0.0220*
Colony status x Worker type 1 0 0.99
Presence absence of mature oocytes, GLMM binomial, n = 210
Colony status 1 5.52 0.01876*
Worker type 1 20.40 < 0.0001***