Just like their ancestors, the Petalgae use camoplasts to change color, but because there are 4 cells now, their photosynthesizing surface has increased and thus it replaced its ancestor. This has not only led to more energy due to more photosynthesis, it has also led to even more specialization of their camoplast. Now they have 5 available phases. Completely black, 1 white cell and 3 black cells, 2 white cells and 2 black cells, 1 black cell and 3 white cells, and all cells white. Although they rarely are fully white, unless the water is extremely hot.
Living Relatives (click to show/hide)
None found. Note that this does not necessarily mean it has no living relatives at all, but that, assuming all taxonomy is filled in, its entire phylum is extinct; any relatives it does have likely do not resemble it.