Scale length comparison of ΣM_mol (l_mol, left panel), ΣSFR (l_SFR, middle panel), and ΣM_⋆ (l_⋆, right panel) of the Cosmic Snake and A521 with other studies from the literature: Regan et al. (2001) in hatched green, Tamburro et al. (2008) in hatched grey, and Leroy et al. (2008) in hatched orange for the z = 0 galaxies, Jafariyazani et al. (2019) in turquoise for the z = 0.1 − 0.42 galaxy stack, Calistro Rivera et al. (2018) in red for the z = 2 − 3 sub-millimetre galaxy stack, and Ushio et al. (2021) in yellow for the z = 1.45 galaxy. Measurements for the Cosmic Snake and A521 are shown with magenta and blue vertical lines, respectively. Because we have two measurements of ΣSFR, we plot the scale length for the Cosmic Snake derived from the Hα emission as a teal line. The magenta line is the scale length of the ΣSFR obtained from the SED fits. We use transparent rectangles around the vertical lines to visualise the uncertainty range.