The causal structure found from super-Earth data using BOSS with FFML score. An undirected edge A − B suggests both directions are possible (either A → B or A ← B), as long as no new colliders are created. Here, the graph means that P → M_p → R_p, P ← M_p ← R_p, or P ← M_p → R_p (but not P → M_p ← R_p), plus an isolated node T_⋆, are equally possible statistically and are together the most likely causal structure.