Sources are ordered along the x-axis from youngest to oldest, based on the diffuse dust temperature T_DD (see Table 1), which is shown in red and corresponds to the rightmost y-axis. The left y-axis shows the molecular cloud temperature (T_MC, in blue), derived from gray-body fits to the SED using the same methodology as for T_DD (see Appendix B). Water and MM detections are indicated above each source, with water maser transitions labeled by their frequency in GHz. All temperatures are in kelvin.