Problem statement: Given an input dataset \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$\mathcal {G}$\end{document}G of a collection of k unrooted gene trees, we seek to find the unrooted species tree topology, assuming gene trees are generated by the MSC model .