Total [N II] luminosity (top panel) and [N III] luminosity (bottom panel) as functions of SFR for the High-z model (red), Dwarfs model (orange), and Schimek et al. (2024a,b) (purple). Both panels include comparisons with the simulated z = 6 sample from Ramos Padilla et al. (2023) (grey circles) and the linear relations from Mordini et al. (2021) based on observations of galaxies in the local Universe. In the top panel we include the [N II] observation from Killi et al. (2023) (black circle) at z ∼ 7, the observed upper limits from Harikane et al. (2020) at z ∼ 6 and Sugahara et al. (2021) at z ∼ 7 (black circles with arrows), and the theoretical relation from Kannan et al. (2022) (z = 6 − 10).