With ERIS we had the objective of reconstructing the evolution of galaxies like the Milky Way using phylogenetic trees, which are already extensively used in other evolutionary studies for biology. Since trees are mathematical structures and graphs, with ERIS we are consolidated an interdisciplinary collaboration between astronomers, biologists and mathematicians, in order to achieve our goal. We focused on reconstructing the evolution of the Milky Way, because this is the best laboratory but we aimed at moving to extragalactic astronomy, by building and interpreting phylogenetic trees that were appropriate for astronomical data. To do so, we simulated the evolution of galaxies, where we knew their shared history. We also used observed data, which allowed us to learn to explore the Milky Way, and ultimately helped us to constrain the theory of galaxy evolution.