About the logo
Charles (Chas) Zartman created the lovely line-drawing, which depicts four species of liverworts, joined in the form of a phylogeny that depicts our best estimate of how the groups to which they belong are related. If you follow the phylogeny and its corresponding liverwort “branch” from the bottom of the logo, the first branching lineage is Haplomitrium (simple thalloid), the next is Conocephalum (complex thalloid), the third, Bazzania (leafy), and the last is Metzgeria (simple thalloid). Part of the Metzgeria thallus is sister to Bazzania in the logo. The other branch of the Metzgeria thallus represents a separate lineage of simple thalloid liverworts. This reflects our current understanding of the paraphyly of the simple thalloid lineage. In addition, you’ll see that the Metzgeria drawing forms the backbone of the tree: symbolic of phylogenetic hypotheses suggesting that the simple thalloid morphology represents the ancestral gametophyte architecture from which all other liverwort body forms arose. This particular hypothesis is controversial and we do not intend to imply that it has been well established.