I have now read the manuscript entitled 'Comparative three-dimensional jaw muscle anatomy of marsupial carnivores (Dasyurus spp.) and the termite-eating Numbat (Myrmecobius fasciatus)' submitted to the journal of morphology. The manuscript presents the first detailed and quantitative description of the jaw muscles in this group of marsupials. Moreover, the authors compare and contrast the more carnivorous Dasyurids with the Numbat which is a termite specialist. I found the paper generally well-written including a careful description of the jaw muscles based on both dissections and contrast-enhanced CT scans. Overall I think this is a solid and important paper that I highly recommend for publication. My only request would be for the authors to also include the fiber length and PCSA data even though they will use it for a future scaling study. Beyond that I only have very minor comments for the authors and congratulate them for the excellent anatomical work coming out of their lab.

minor comments:

line 38: any member of the group

line 79: myrmecophagous diet ...

line 103: to improve the mechanical advantage for food processing

Lines 106-108: I was a bit surprised by this statement and I was wondering what the evidence was for the contribution of geno, mylo and sternohyoid muscles to jaw opening. I would like to see this supported by references as I very much doubt this is the case or a general mammalian pattern.

line 123: in the numbat...

line 156: determine Lugol penetration

line 177: even if you se them in a future study I would think it would be coherent to present them here. This could enrich the discussion as well.

Line 203 and elsewhere: I would not say that rostral fibers are aponeurotic... if they are muscle fibers then by definition they cannot be aponeurotic. I believe that it would be better to state that the muscle takes it origin by means of an aponeurosis ...

line 205: muscles were oriented

lines 226-231: what was the proportion of the anterior and posterior part of the ZM ?

line 235: I presume you mean zygomaticomandibularis and not deep masseter here.

line 252: the insertion was found...

line 253: In D. maculatus the point of insertion ...

line 354: this is extremely bizarre and very interesting.

line 365: maybe three elements rather than patterns?

line 367: unusual configuration maybe rather than presentation ?

line 381: The Dasyurus species ...

line 400: as extreme an enlargement... as many carnivorans do.

line 407: that the jaw muscles...

line 430: of the masticatory musculature

line 459: the most dramatic modification

line 509: developing a deeper understanding of ...