 In addition to adding more evidence in cases where systematists already had a great deal of it, molecular studies can shed light on cases where other sources of evidence are extremely weak. For example, molecular data may preserve deep phylogenetic history otherwise obscured at the morphological level by millions of years of adaptive changes. Phylogeneticists depicting the very earliest branches in plant and animal phylogenies, as well as relationships between the different groups of eukaryotes, recognized how molecular data could both test and enrich these deep phylogenetic hypotheses (Kenrick &amp; Crane 1997; Baldauf 2003). Subsequent molecular phylogentic analyses have demonstrated the fruitfulness of using molecular data (e.g., amino acid sequences, RNA transcriptomes, and nuclear and mitochondrial genomes) for constructing deep phylogeny hypotheses (Heckman et al. 2001; Dunn, Giribet, Edgecombe, &amp; Hejnol 2014).