This avian genome project is first-rate science, and having the assemblies, annotation files, multiple alignments and ortholog lists available in GigaDB will be a fantastic boon to many biologists. I am enthusiasic about the idea of a paper accompanying those data appearing in GigaScience. On this other hand, I have several concerns about the current manuscript. Comment #1 is left to the editor's discretion, while I consider #2 to be compulsory.

1. Most or all of the material presented in the paper is probably in the Methods section and/or supplement of one or both of the papers numbered 1 and 2. Of course, it is up to the GigaScience editors to decide how much of a publication can appear elsewhere, but as a reviewer I cannot understand the degree of redundancy without seeing the other manuscripts, and cannot evaluate appropriateness without seeing a statement about this issue from the editor.

2. The manuscript and supplement need to be read carefully by someone proficient in the English language; as things stand, the manuscript needs extensive editing. One way forward could be for the authors to send me copies of the submitted papers and supplements, so I can comment on the relationship of the GigaScience manuscript to the others. If the English-proficient authors are too busy to edit the manuscript, they can send me Word versions so I can use Track Changes.

3. (minor discretionary revision). I recommend that the authors reformat Tables 1 and 2 so that line-breaks do not split words or numbers; in particular, giving 5 digits after the decimal point in Table 2 is over-kill.