Fig. S1.

Speed (here frequency) regulation model can segment elongating and nonelongating tissues. (A) Core mechanism of speed/frequency regulation model: The speed/frequency of a molecular clock is regulated by the concentration of a speed/frequency regulator. High phase of the oscillator is shown in blue, and low phase is shown in white. The speed/frequency regulator is shown in gray. (B) Speed/frequency regulation model can operate in a gradient-based mode to pattern nonelongating tissues (Left) and in a wavefront-based mode to pattern elongating tissues (Right).