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Context. Deur (2014) and Winters et al. (2023) proposed an empirical relationbetween the dark to total mass ratio and ellipticity in elliptical galaxiesfrom their observed total dynamical mass-to-light ratio data M/L = (14.1 +/-5.4){\epsilon}. In other words, the larger is the content of dark matter in thegalaxy, the more the stellar component would be flattened. Such observationalclaim, if true, appears to be in stark contrast with the common intuition ofthe formation of galaxies inside dark halos with reasonably spherical symmetry.Aims. Comparing the processes of dissipationless galaxy formation in differenttheories of gravity, and emergence of the galaxy scaling relations therein isan important frame where, in principle one could discriminate them. Methods. Bymeans of collisionless N-body simulations in modified Newtonian dynamics (MOND)and Newtonian gravity with and without active dark matter halos, with bothspherical and clumpy initial structure, I study the trends of intrinsic andprojected ellipticities, S\'ersic index and anisotropy with the total dynamicalto stellar mass ratio. Results. It is shown that, the end products of both coldspherical collapses and mergers of smaller clumps depart more and more from thespherical symmetry for increasing values of the total dynamical mass to stellarmass, at least in a range of halo masses. The equivalent Newtonian systems ofthe end products of MOND collapses show a similar behaviour. The M/L relationobtained from the numerical experiments in both gravities is however ratherdifferent from that reported by Deur and coauthors.

Dissipationless collapse and the dynamical mass-ellipticity relation of elliptical galaxies in Newtonian gravity and MOND