Fig. 11. Three hypotheses for the temporal pattern in the activation of the M. adductor mandibulae externus superficialis (AMES) and M. protractor pterygoideus (PP). (A) The AMES maintains a prolonged contraction resulting in sustained venom pressure (VP) within the venom gland; under this hypothesis the kinematics of the spit (SK) would be characterized by marked increases and decreases in venom flow. (B) Temporally congruent patterns in the AMES and PP, leading to congruent bell-shaped curves for venom pressure and spit kinematics. (C) Prolonged contraction of the PP with intermittent contract of the AMES, leading to variable patterns of venom pressure and spit kinematics.