Extremality of rational tails boundary strata in \(\overline{\mathscr{M}}_{g,n}\) (Q2147384)

In this paper, it is shown that a large family of boundary strata of rational tails type are extremal in their corresponding effective cone. In particular, it is proven that all boundary strata in genus zero are extremal, and based on some evidence, the author conjectures the truth of this statement in any genus. The results of this paper are in parallel with the work of \textit{D. Chen} and \textit{I. Coskun} [Proc. Lond. Math. Soc. (3) 111, No. 1, 181--204 (2015; Zbl 1357.14039)].