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We analyse the mass density distribution in the centres of galaxies acrossfive orders of magnitude in mass range. Using high-quality spiral galaxyrotation curves and infrared photometry from SPARC, we conduct a systematicstudy of their central dark matter fraction ($f_{\rm DM}$) and their massdensity slope ($\alpha$), within their effective radius. We show thatlower-mass spiral galaxies are more dark matter dominated and have more shallowmass density slopes when compared with more massive galaxies, which havedensity profiles closer to isothermal. Low-mass ($M_{\star} \lesssim 10^{10}\,\rm M_{\odot}$) gas-rich spirals span a wide range of \fdm\ values, butsystematically lower than in gas-poor systems of similar mass. With increasinggalaxy mass, the values of \fdm\ decrease and the density profiles steepen. Inthe most massive late-type gas-poor galaxies, a possible flattening of thesetrends is observed. When comparing these results to massive ($M_{\star} \gtrsim10^{10}M_{\odot}$) elliptical galaxies from SPIDER and to dwarf ellipticalsfrom SMACKED, these trends result to be inverted. Hence, the values of both$f_{\rm DM}$ and $\alpha$, as a function of $M_{\star}$, exhibit a U-shapetrend. At a fixed stellar mass, the mass density profiles in dwarf ellipticalsare steeper than in spirals. These trends can be understood by stellar feedbackfrom a more prolonged star formation period in spirals, causing atransformation of the initial steep density cusp to a more shallow profile viadifferential feedback efficiency by supernovae, and by galaxy mergers or AGNfeedback in higher-mass galaxies.

The dichotomy of dark matter fraction and total mass density slope of galaxies over five dex in mass