Table 2.

Percentage of total masticatory nPCSA represented by each muscle, model input forces, resulting applied forces, and % applied forces representing the primary jaw adductors, neck muscles and forces pushing upward through the spine in models of Callithrix jacchus and Saguinus fuscicollis at a gape angle representing bark-gouging (50°). Applied masticatory force is less than input masticatory force because it includes only those portions of temporalis muscles that produce positive moments about the TMJ axis. Note that sums of applied force are identical for each model.

	% Masticatory nPCSA	Input force (N)	Applied force (N)	% Applied force
C. jacchus (50°)
Temporalis	48	107.87	43.87	27
Masseter	39	87.64	87.64	55
Medial pterygoid	10	22.47	22.47	14
Lateral pterygoid	3	6.74	6.74	4
Neck muscle		69.76	69.76
Spine		52.33	52.33
Sum of applied force			282.81
S. fuscicollis (50°)
Temporalis	49	87.46	69.70	43
Masseter	39	69.61	69.61	43
Medial pterygoid	9	16.06	16.06	10
Lateral pterygoid	3	5.35	5.35	3
Neck muscle		69.76	69.76
Spine		52.33	52.33
Sum of applied force			282.81