The evolutionary histories of species and genes can be discordant , necessitating a distinction between genes trees and species trees. Incomplete Lineage Sorting (ILS), modeled by the multi-species coalescent (MSC) model , is one of the main causes of discordance. A fast approach for estimating the species relationships in the face of such discordances is to first estimate a gene tree for each gene and to summarize the gene trees to build a species tree. The summary method, thus, takes as input a set of gene trees and returns a species tree. A desirable property for a summary method is statistical consistency (a theoretical guarantee that it converges in probability to the correct species tree as the number of error-free genes increases). Many statistically consistent summary methods are available (e.g., ASTRAL [3, 4], BUCKy-population , and MP-EST ), and coalescent-based species tree estimation is a vibrant field of research, with many recent examples of successful biological analyses [7–9] (see [10–14] for criticism of these methods, especially their sensitivity to gene tree error).