Schematic of evolutionary relationships within the green algal lineage showing distribution of EFL and EF-1α and possible events explaining the distribution. A phylogeny of the Plantae, with the known presence of either EFL or EF-1α in extant lineages plotted at the tips of each branch (EFL is a square containing "L" and EF-1α is an octagon containing an "α"). All known rhodophytes and glaucophytes contain EF-1α, as do most other eukaryotic lineages, so the ancestor in inferred to have contained EF-1α as well (indicated by a gray octagon at the base of the tree). Also plotted is one possible explanation for the current distribution of the two genes in the green lineage, where EFL was gained once in the ancestor of the green viridiplantae (indicated by the green box), and subsequently either EFL or EF-1α lost in several lineages each (indicated by red boxes with indicated which gene would have been lost). Other models to explain this distribution that include multiple origins of EFL are also possible, but are not shown for simplicity. The tree of the green lineage is based on Figure 1 and other analyses .