Table 1.
Species, location, sex and number of saliva samples used for measuring amylase and cortisol.
Figure 1.
Average salivary alpha amylase (sAA) activity in females and males of the four ape species.
The boxes illustrate the 25th and 75th percentiles, bars indicate medians, and circles indicate outliers. The y-axis is log transformed. Sample sizes: total N = 625: Nbonobo female = 92, Nbonobo male = 98; Nchimpanzee female = 113, Nchimpanzee male = 41; Ngorilla female = 60, Ngorilla male = 39; Norangutan female = 107, Norangutan male = 75.
Table 2.
Results of the general linear mixed models (GLMMs) of the four subsets for each species with sAA activity as response variable, and with age, time of day (both z-transformed) and sex as fixed effects.
Table 3.
Results of the general linear mixed model (GLMM) for subsets of females with sAA activity as response variable, species, age and time of day as fixed effects, and zoo and subject as random effects (MCMC = Markov Chain Monte Carlo; SE = Standard error).
Table 4.
Results of the general linear mixed model (GLMM) for subsets of males with sAA activity as response variable, species, age and time of day as fixed effects, and zoo and subject as random effects (MCMC = Markov Chain Monte Carlo; SE = Standard error).
Figure 2.
Average salivary cortisol concentrations for females and males of each species.
The boxes illustrate the 25th and 75th percentiles, bars indicate median, and circles indicate outliers. Cortisol values on the y-axis are log transformed. Sample sizes: total N = 615, Nbonobo female = 90, Nbonobo male = 94; Nchimpanzee female = 112, Nchimpanzee male = 39; Ngorilla female = 59, Ngorilla male = 39; Norangutan female = 107, Norangutan male = 75.
Table 5.
Results of the general linear mixed models (GLMMs) of the four subsets with salivary cortisol levels as response variable, and with age, time of day (both z-transformed) and sex as fixed effects.
Table 6.
Results of the general linear mixed model (GLMM) obtained by analysing subsets of samples from females, with salivary cortisol concentration as response variable, with species, age and time of day as fixed effects, and zoo and subject as random effects (MCMC = Markov Chain Monte Carlo; SE = Standard error).
Table 7.
Results of the general linear mixed model (GLMM) obtained by analysing subsets of samples males, with salivary cortisol concentration as response variable, with species, age and time of day as fixed effects, and zoo and subject as random effects (MCMC = Markov Chain Monte Carlo; SE = Standard error).