Table 1.

Models fitted in lme4 to study variation in FIDs of skinks

Model	Fixed effects	Random effects	AIC
M0FID—Regression	Observer, site, logSD	N/A	N/A
M1FID—Random intercept	Observer, site, logSD, trial	Intercept: skink	−191.7
M2FID—Random intercept/fixed interaction	Observer, site, logSD, trial, site*trial	Intercept: skink	−191.7
M3FID—Random intercept/random slope	Observer, site, logSD, trial	Intercept: skinkSlope: trial	−196.7
M4FID—Random intercept/random slope with site–trial interactions	Observer, site, logSD, trial, site*trial	Intercept: skinkSlope: trial	−195.23

Dependent variable is logFID for all models. Bold text indicates model with lowest AIC.

^*Indicates an effect interaction.