Data from: Characterizing and comparing phylogenies from their Laplacian spectrum

Phylogenetic trees are central to many areas of biology, ranging from
population genetics and epidemiology to microbiology, ecology, and
macroevolution. The ability to summarize properties of trees, compare
different trees, and identify distinct modes of division within trees is
essential to all these research areas. But despite wide-ranging
applications, there currently exists no common, comprehensive framework
for such analyses. Here we present a graph-theoretical approach that
provides such a framework. We show how to construct the spectral density
profile of a phylogenetic tree from its Laplacian graph. Using ultrametric
simulated trees as well as non-ultrametric empirical trees, we demonstrate
that the spectral density successfully identifies various properties of
the trees and clusters them into meaningful groups. Finally, we illustrate
how the eigengap can identify modes of division within a given tree. As
phylogenetic data continue to accumulate and to be integrated into various
areas of the life sciences, we expect that this spectral graph-theoretical
framework to phylogenetics will have powerful and long-lasting
applications.