Comparison of heterochrony rates. Box graph showing heterochrony rates of all events in the superconsensus tree. The heterochrony rate represents the total number of heterochronic shifts (early and late) for a specific event, multiplied with its mean bootstrap value. The color code for the different classes of events is given at the bottom. (a) Heterochrony rate for all events in the data set. (b) Heterochrony rate of events with clear segment affiliation, sorted from anterior to posterior (A1, A2, Md, Mx1, Mx2, T1, P6) and compared for the three different tissue types (appendage buds, ganglion anlagen, and muscle precursors). The heterochrony rates shown here for muscle precursors represent mean values of all myogenic events recorded for the respective segment. Events that are affiliated with the telson (PPN, lmp-post) are also included. Abbreviations for events in (a) are used as listed in Table 1. In (b), the body segments are labeled with the abbreviations of the corresponding appendage: A1 first antenna, A2 second antenna, Md mandible, Mx1 first maxilla, Mx2 second maxilla, T1 first thoracopod, and P6 sixth pleopod.