Table 1.

Effects of sex, age and body mass on mass, metabolism and ventilation during cold exposure in 211 deer mice ranging in age from 27 days to 1863 days

MassF1,205=24.5, P<0.000001*M: r=0.432, P=0.000004*
F: r=0.521, P<0.000001*
BMRF1,201=8.2, P=0.0046*M: r=0.56, P<0.000001*M: r=-0.12, P=0.23
F: r=0.57, P<0.000001*F: r=0.010, P=0.92
O2max F1,203=1.2, P=0.275r=0.664, P<0.000001*r=-0.201, P=0.00316*
O2sum F1,202=0.002, P=0.96r=0.506, P<0.000001*r=-0.217, P=0.00209*
f F1,200=7.8, P=0.00572*M: r=0.083, P=0.40M: r=-0.27, P=0.00495*
F: r=0.006, P=0.95F: r=-0.384, P=0.000094*
V T F1,198=1.7, P=0.20r=0.329, P=0.0000017*r=0.092, P=0.19
min F1,198=0.002, P=0.97r=0.336, P<0.000001*r=-0.071, P=0.31
E O2 F1,198=0.13, P=0.72r=0.10, P=0.14r=-0.19, P=0.0070*
  • BMR, basal metabolic rate; O2max, maximal oxygen consumption in exercise; O2sum, maximal oxygen consumption in thermogenesis; f, breathing frequency; VT, tidal volume; min, minute volume; EO2, oxygen extraction.

    Age, mass and metabolism were loge-transformed prior to analysis. ANCOVA with mass and age as covariates was used to test for sex differences, and multiple regression was used to examine the effects of age and mass. Separate partial correlation coefficients (r) and P values are given for males (M) and females (F) for variables where the sexes differed significantly. P values with an asterisk (*) remained significant after sequential Bonferroni correction (adjustedα =0.008; Rice, 1989).