Table 1.

Results from kinematic analysis of the ballistic phase (first 20 ms) of mouth opening in freely behaving toads

Gape distance (mm)xt (mm)r2
IndividualIn:out lever ratioNMax/MinMax/Minkt (N m-1)beff (Ns m-1)Max/Min
11:7.91128.3/19.23.7/2.5712±735.6±0.60.998/0.981
21:7.92223.9/18.73.1/2.4582±284.4±0.20.999/0.989
31:8.62219.1/11.02.5/1.4522±404.1±0.30.998/0.989
41:7.71624.8/22.53.6/2.9508±424.4±0.30.999/0.989
Mean1:8.0-24.0/17.93.2/2.35814.60.999/0.987
s.e.m.0.2-1.9/2.40.3/0.3470.30.0003/0.002
  • Values for kt and beff are means± s.e.m. For individual and in:out lever ratio of the depressor mandibulae muscles, N=4; listed N values = number of feeding trials per individual.

    xt, total displacement of the depressor mandibulae muscles and extra-muscular connective tissues; kt, mean total spring constant; beff, mean effective damping coefficient; r2, least-squares fit [between observed and predicted total displacement (xt) vs time].