Temporal evolution of various Amaryllis properties: L_OIII/L_CII (top panel), the ionization parameter U_ion (second panel), gas metallicity, Z (third panel), gas number density, n (fourth panel), and star-formation variability, SFR_3 Myr/SFR_50 Myr (bottom panel). The correlations between L_OIII/L_CII and each other property are presented in Table 2. The vertical dashed green lines correspond to major merger events, and the dotted red line indicates the snapshot with the highest [OIII]/[CII].