Table 2.

Summary of PC loadings from a principal component analysis on 19 muscle-activity patterns variables describing strike, chew and rake feeding behaviours in O. mykiss

Principal component loadings
Variance explainedPC1 55.5%PC2 27.7%PC3 7.4%PC4 3.9%
MAP variables
   Adductor mandibularis activity duration 78.47 37.12 –7.16 –16.73
   Protractor hyoideus onset timing 70.08 –55.49 8.18–7.90
   Protractor hyoideus activity duration 48.45 48.50 12.46 17.40
   Adductor mandibularis onset timing 38.79 –27.60 10.01 17.75
   Hypaxialis activity duration 18.09 2.07–9.201.68
   Sternohyoideus activity duration 15.98 –8.38 –36.41 7.73
   Sternohyoideus onset timing –15.54 11.0414.70–8.51
   Hypaxialis onset timing–9.459.39–0.75–3.55
   Adductor mandibularis integrated area4.434.140.30–0.03
   Sternohyoideus integrated area3.510.66–2.481.66
   Epaxialis activity duration2.825.30–9.952.63
   Protractor hyoideus integrated area2.815.380.810.26
   Hypaxialis integrated area1.910.61–0.330.04
   Epaxialis integrated area1.150.94–0.420.81
   Sternohyoideus mean amplitude0.030.020.010.01
   Epaxialis mean amplitude0.020.010.010.01
   Protractor hyoideus mean amplitude–0.020.010.00–0.02
   Hypaxialis mean amplitude–0.010.000.01–0.01
   Adductor mandibularis mean amplitude–0.010.010.010.01
F-statistics (F2,72)58.16, P<0.001*16.53, P<0.001*15.19, P<0.001*2.73, P=0.07
Rake ≠ chew P<0.05 * P=0.08P=0.13
Rake ≠ strike P<0.001 * P=0.15P=1.00
Chew ≠ strikeP=0.13P=1.00P=0.13
  • Summary ANOVAS and Bonferroni-corrected post-hoc test P values along PC axes are also given

    MAP, muscle-activity pattern; bold type signifies, high PC loadings (see text) and significant P-values

  • * Significant after Bonferroni correction