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tokens: respect to the location of the analogous peak observed for S Mon. Sung Bessell (2010) examined the median ages and cumulative age distributions of PMS stars in the various NGC 2264 subregions, to derive some information on the star formation processes within the region. The picture they deduced from their analysis is overall consistent with the scenario we outlined here: a picture of sequential star formation, where objects that populate the Halo and Field regions were formed first, followed by stars in S Mon and Cone (H), then sources in Cone (C) and, finally, those in the Spokes subcluster. The separate analysis we conducted here for disked vs. non-disked (and accreting vs. non-accreting) objects as a function of age allowed us to: i) confirm the model-based indication of an age spread by the association with measurable quantities, such as the presence of disks or accretion; ii) obtain a more detailed overview of the dynamical evolution of the cluster; iii) explore the mechanisms and characteristic timescales of evolution of PMS objects across the region (see Sects. 5.1 and 5.3 ). 5.3. Impact of environmental conditions on disk evolution In their investigation of the star formation history of NGC 2264, Sung Bessell (2010) showed that, while the age distribution of the S Mon population exhibits a significantly different behavior from those of the Spokes or Cone (C) populations (in the sense that the probability that they are drawn from the same parent distribution is very low), the populations of S Mon and of Cone (H) exhibit very similar distributions in age. However, some differences between the two regions appear when we restrict our analysis to disk-bearing or accreting objects (see Table 2 ). Namely, while the median ages associated with Class III objects in S Mon and in Cone (H) are similar to each other, the median age of disk-bearing objects in S Mon is noticeably lower than that of disk-bearing objects projected onto Cone (H). The difference is more marked when only CTTS are considered: a K-S test applied to the age distributions of accreting objects in S Mon and in Cone (H) returns a probability of 0.03 that they are drawn from the same population. This difference in median age between the two populations might be understood if objects in S Mon were formed at a later time than objects in Cone (H). However, the fact that S Mon hosts a significant fraction of Class III objects at any given age, and the fact that the number of Class II objects located in S Mon decreases sharply after 2.5 Myr (lower right panel of Fig. 11 ), would rather suggest that the characteristic timescales associated with disk accretion and disk evolution are shorter in the northern half of NGC 2264 than elsewhere within the region. This may result from non-uniform environmental conditions across the cluster. The S Mon region shown in Fig. 10 is distinguished by the presence of the massive binary S Mon (the primary component is an O7 V star and the secondary