Fig. 10. Quantitative inputs and results of the odontophore-centric model of a polyethylene tube swallow, magnetic resonance imaging (MRI) sequence 7732-S3, frames 15-38. Each frame is 310ms (real time). (A) Radular stalk angle, measured from each MRI frame. These values were direct inputs into the model. (B) Shape space analysis of MRI frames 15-38. (C) Shape space analysis of the corresponding odontophorecentric model frames. The four key landmarks of the feeding cycle (start of protraction, peak protraction, peak retraction and return to rest; gray symbols are defined in Fig. 3C) and general progress through shape space are in fair agreement, but the exact paths are not identical. (D) Model I2 and I7 muscle lengths. I7 doubles and I2 more than doubles its length during t1. Intervals t1, t2, t3 and t4 are defined in Materials and methods. (E) Model I1/I3 muscle antero-posterior length. (F) Model I1/I3 muscle ring widths (medio-lateral). The rate of width changes is less than in the radula-centric model (see Fig. 8E).