Comparison between the observed structural properties of Cha I and simulated clusters with high (n_stars = 1000 stars pc^-3, top panels) and low (n_stars = 100 stars pc^-3, bottom panels) initial stellar density from Parker et al. (2014). The panels on the left and on the right show the Q-parameter as a function of Σ_LDR (i.e., the ratio between the median superficial density of the most massive stars and the rest of the sample) and Λ_MSR (for the ten most massive stars), respectively. The simulations differ for the initial virial ratio α_vir and the initial level of substructure (D = 1.6 is a highly substructured cluster and D = 3.0 is a roughly uniform sphere). Blue crosses and black circles represent the simulated clusters at the initial conditions and after 2 Myr evolution, respectively. Green and black dots represent the properties of Cha I for the full sample of members and only for the stars in the embedded region within the smallest ellipse in Fig. 6, respectively. The red lines trace the Q-parameter estimated for the pre-stellar cores with errors.