Question: What subtypes of polychaetes were useless classifications, according to the 2007 study?
Sentence: In 2007 Torsten Struck and colleagues compared 3 genes in 81 taxa, of which 9 were outgroups, in other words not considered closely related to annelids but included to give an indication of where the organisms under study are placed on the larger tree of life.
Answer in sentence: no