I just sent this to my cell physiol prof:
The tree in slide 9 of the first lecture powerpoint is absolutely awful and grotesquely outdated (apparently based on Woese 1990). First of all, it is well-supported that the root is more likely to lie either between Eubacteria and Archaea+Eukarya, or within Eubacteria (I'm partial to the latter). It's rather murky in that particular diagram. Secondly, the eukaryote side of the tree makes one want to cry/punch a giant hole in the wall: Trichomonas and Giardia aren't exceptionaly likely to be the basal eukaryotes, and group reasonably well with Trypanosoma+Euglena, forming what may well be a monophyletic group. In any case, Trichomonas and Giardia seem to form a clade.The diagram comes from the "Big Alberts" text, 2008 edition. They should bloody know better by now! >.<
Dicty is WAAAY more closely related to Humans+Yeast than either Maize or Paramecium -- the later two are on a fundamentally different branch of eukaryotes -- the bikonts (eg. Cavalier-Smith 2009 J. Euk. Microbiol) or the corticates (Cavalier-Smith 2010 Biol. Lett.) Dicty, Humans and Yeast are members of a quite well-supported group (Unikonts), and this tree erroneously suggests that multicellularity evolved in the common ancestor of Plants, Animals and Fungi, which is completely wrong. Multicellularity evolved in each of those lineages independently, and in quite a few other lineages as well, up to ~16 times in the Eukaryotic kingdom (King 2004 Dev. Cell) and arguably a few times among prokaryotes as well (eg. Streptomyces).
I can't believe this is in a 2008 edition of the textbook! This tree has been outdated for at least a decade! How does one go about formally complaining with things like this? I refuse to let any suggestion of "crown/higher eukaryotes" vs. "stem/lower eukaryotes" go by unnoticed. The very notion of higher/lower organisms is thoroughly wrong and must be abandoned. Even in an introductory diagram. ESPECIALLY in an introductory diagram. Especially when they have the nerve to HIGHLIGHT Maize, Yeast and Humans as if they're some special enlightened life forms.
The era of Woese 1990 is over. We can move on anytime now...
Candidate for the Twisted Tree of Life Award?
Also, their 'interesting' spelling of eukaryotes is in itself a rantworthy topic for some other day...