Finding. Yellow-green algae now have a three-genome tree that does not argue with itself. Nucleus, plastid, and a 31-gene mitochondrial matrix draw the same shape. That tree says simple multicellularity evolved at least four times from unicells, and each time reproduction shifted from many autospores toward single monospore or akinete packages. Go back to unicellular and autospores return. Mitochondria here are a concordant historian.
Why this paper matters
Xanthophytes were a systematic mess and a good test of how sex/propagules stabilize multicellularity. Concordant mitochondrial data make the revision safer. The organelle is not the patient.
What they actually measured
Phylogenomic matrices, taxonomic acts, ancestral reconstruction of multicellularity and reproductive mode.
How to read the score
High fifties. Score 57.
What to do with it
If you classify heterokonts or study early multicellularity, take the tree and the four-origin claim. Skip if you wanted OXPHOS. The directional implication is that simple multicellularity in this class repeatedly arrives with a one-propagule reproductive strategy, and mitochondria agree on the phylogeny.