Table 1.

Force and timing parameters for forelimbs, hindlimbs and tail in Alligator mississippiensis

VariablesForelimbHindlimbPTail*
Support duration (s)1.51±0.091.57±0.070.814-
Peak vertical force (BWU)0.41±0.010.53±0.01<0.0005**0.08±0.01
Vertical impulse (BWU·s)0.36±0.020.51±0.020.005**0.12±0.01
Net craniocaudal impulse (BWU·s)-0.01±0.010.04±0.01<0.0005**-0.03±0.01
Braking impulse (BWU·s)-0.02±0.01-0.01±0.010.001**-0.03±0.01
Propulsive impulse (BWU·s)0.01±0.010.05±0.030.002**0
Peak breaking force (BWU)-0.05±0.02-0.05±0.020.414-0.02±0.02
Peak propulsive force (BWU)0.04±0.030.07±0.030.001**0
Peak mediolateral force (BWU)0.07±0.010.10±0.040.001**-0.02±0.01
Net mediolateral impulse (BWU·s)0.07±0.040.09±0.040.035-0.01±0.01
Relative time to peak vertical force (% support duration)68.2±0.934.5±0.9<0.0005**-
Relative time to braking-propulsion transition (% support duration)62.0±1.015.2±0.7<0.0005**-
  • Values are means ± s.e.m. Sample sizes for limb and tail data are 30 and 17, respectively.

  • * Tail impulses are estimated over the mean support duration of the limbs (1.54 s)

  • ** Fore- and hindlimbs significantly different at P<0.006, established by sequential Bonferroni correction α/k=0.05/9