Looks like a species can be more evolved. I think when evolutionary biologists say that "no species is more evolved than another" they're addressing the people who think "humans are so smart so they must be more evolved." or "look at those dumb worms, they should try evolving more".
Source: ”However, advanced students may be interested to know that in the specialized phylogenies where the branch length does mean something, a longer branch usually indicates either a longer time period since that taxon split from the rest of the organisms on the tree or more evolutionary change in a lineage! Such phylogenies can usually be identified by either a scale bar or the fact that the taxa represented don't line up to form a column or row. In the phylogeny on the left below,1 each branch's length corresponds to the number of amino acid changes that evolved in a protein along that branch. On longer branches, the protein collagen seems to have experienced more evolutionary change than it did along shorter branches." From Understanding Evolution (Berkeley)
