Some consequences of a definition of the 'static biting force' in cichlid fishes by BAREL (1983) are explored. A free-body diagram of the lower jaw shows that apart from the forces of the food and the jaw adductor muscle on the jaw other forces are needed to obtain static equilibrium. The introduction of joint forces solves this problem. Our analysis also shows that in many biting activities a locomotor force is required. Starting from an alternative definition for the static biting force, quite different results may be obtained for the space requirements of the jaw adductor muscle and the lower jaw as compared to those of BAREL.