Instruction: You are one of the reviewers, your task is to write a review for the article. You will be given the title of the article, the number of the round in which the article is located, and your order among the reviewers.

Input:
Title: REVISION OF THE LATE JURASSIC DEEP-WATER TELEOSAUROID CROCODYLOMORPH TELEOSAURUS MEGARHINUS HULKE, 1871 AND EVIDENCE OF PELAGIC ADAPTATIONS IN TELEOSAUROIDEA
Review round: 1
Reviewer: 2

Output:
Basic reporting: no comment
Experimental design: no comment
Validity of the findings: no comment
Additional comments: Overview: The authors describe new material of the poorly known teleosauroid species “Teleosaurus” megarhinus, providing it with a new genus name and establishing diagnostic characters for the taxon. In addition to extensively describing the fragmentary material, they note some characteristics that may be related to adaptation to a more pelagic lifestyle. This is interesting because this taxon is one of the only teleosauroids known from deep water deposits (whereas most teleosauroids are known from estuarine/coastal deposits), bolstering the hypothesis that this species may have been evolving towards a more pelagic lifestyle than other members of the group. In general, this is a well written and well-done study. I particularly appreciate the authors’ extensive comparisons of Bathysuchus material with other teleosauroid species. I do have a large number of comments, but these are primarily related to relatively minor changes to figures and text. There is an issue with the phylogenetic analysis (see below) that needs to be rectified, but it doesn’t affect the overall results of this study. I look forward to the publication of this manuscript and the continuing clarification of teleosauroid taxonomy and phylogeny by this working group.

General comments:
The authors make a lot of comparisons to A. priscus. Perhaps it would be helpful to add a figure showing the reduced ornamentation of skull and osteoderms and possibly the reduced limb elements in this taxon? This would help clarify the discussion section on pelagic adaptations (and with some of the comparisons noted in the description).

The authors note in the “systematic paleontology” section under “Holotype” that this specimen is severely diagenetically damaged and partially reconstructed. However, they rarely discuss how this diagenetic alteration may affect the morphological interpretations they are making (e.g., the 8-shape of the external naris looks to be exaggerated by dorsoventral deformation). It would also be helpful to mention which parts have been reconstructed (though this could be solved by modifying the figure – see figure comments below).

While a lot of the comments below will likely sound as if I am disagreeing with the authors’ interpretation of the morphology of some of these specimens, this is not my intent. In most cases I’m not disagreeing, but rather pointing out that some of the characters they emphasize are from deformed specimens or are otherwise difficult to observe (e.g. in specimens preserved in slabs), or in some instances that there is conflict in the published literature about a particular feature. I’m noting these so the authors can critically assess their own interpretations. If they are confident in their assessments, then by all means they should publish as such. Another note that applies more generally to the description and comparisons with other taxa – I think the authors should be careful to distinguish when their statements are based on direct observation (i.e., character is clearly visible on a specimen) vs. an interpretation (e.g., “we believe this specimen had this character, though it has been altered by deformation”).

On the online supplementary file: The title used in the online supplementary file differs from the title of the manuscript. The order of authors also differs. Additionally, there are some “track changes” comments remaining in the document.

Issues with the phylogenetic data matrix: I think the data file posted is not the one analyzed for this study. The manuscript says the matrix consists of 142 taxa. However, while the one currently posted does have 142 OTUs, it has Bathysuchus as 2 separate OTUs (the second one presumably being the one adding the Quercy specimen information). Additionally, the taxon Steneosaurus meretrix is included in the data file but is not present in Fig. 6. So, it would seem that the data set analyzed for the manuscript actually has 140 taxa (if S. meretrix is not supposed to be included and excluding one Bathysuchus specimen for each analysis) or 141 (if S. meretrix was included but is missing on the figure for some reason). When I exclude the second Bathysuchus OTU, which should give me the first analysis in the manuscript, I get different results than reported. The topology of teleosauroidea is identical to that of Fig. 6, but the tree length is longer (1504 vs 1488 reported) and the number of trees is much larger (14904 vs 102 reported). Excluding Steneosaurus meretrix only reduces tree length by 2. I also think that the authors may not have actually treated their additive characters as additive when they ran the analysis. If I set all characters to unordered, I get a tree length closer to that reported (1486 vs 1488), but the number of trees is still higher (1944 vs 102), and the topology of teleosauroidea is still identical. Running what should be the equivalent of the second analysis (excluding the first Bathysuchus OTU) gives again, a higher tree length (1507 vs. 1491) and a higher number of trees (4968 vs 75). Regardless, the authors should double check their phylogenetic analyses and make any changes necessary to their results section. They should also upload a separate data file for each analysis so there is no ambiguity as to how to reproduce their results.

Specific comments:
Line 30: “is” should be “are” (unless UK English typically treats “whereabouts” as singular); also in line 207

Line 83: “Vignaud (1997)” should be 1995

Lines 102-104: “the supertree analysis of Bronzati...” – This statement isn’t entirely true. Bronzati et al. merely included Mueller-Töwe’s tree in their analysis. I don’t know that they considered the “validity” of the taxa sampled in that analysis. Their recovery of S. megarhinus as sister to Teleosaurus isn’t independent of the Mueller-Töwe analysis. I suspect that no other tree included sampled S. megarhinus, so this is the only relationship for this taxon that could have been recovered.

Line 123: I believe a colon is missing following the word “locality”

Line 126: “continue” should be “continues”; “rock” should be “rocks”

Line 130: “concetional” should be “concretional”

Line 132: “Zone” should be “zones”

Line 134: either there needs to be commas offsetting the clause “spanning the Middle-Late Jurassic”, or the word “that” needs to be moved to follow this clause.

The boilerplate text about ICZN compliance is repeated (lines 145-154 and 187-196)

Lines 213-214: On Platysuchus having 5 premaxillary teeth – On which specimen are the authors basing this number? The SMNS holotype specimen and Urweltmuseum Hauff specimen are both preserved in dorsal view in slabs. I’m not sure it is possible to determine the number of alveoli in these specimens (Mueller-Töwe 2006 suggests 3 premax teeth. I have “4?” written in my notes from when I looked at the holotype – though I don’t recall how I got that number). I don’t know of any Platysuchus specimens preserved with the ventral surface of the premax visible (though they very well could exist somewhere). The only Platysuchus specimen referenced that shows a ventral view of the premax is the Luxembourg specimen. However, I’m not sure I’m convinced that this specimen is attributable to Platysuchus. Johnson et al. attribute it based on it having 5 premaxillary teeth and first and second alveoli “similar in size” rather than the “first slightly smaller than the second” as in S. bollensis. The distinction of “similar in size” vs. “slightly smaller” doesn’t seem like a clear diagnostic feature. Again, as I don’t know of any Platysuchus specimens showing the ventral surface of the premax, I’m not sure how this diagnostic feature (or number of premax teeth) was determined in the first place. The Luxembourg specimen also distinctly lacks the lateral expansion of the premaxilla found in the holotype and UH specimens.

Line 219: “anterior and posterior processes of the premaxilla” – I believe the authors are here referring to short processes along the anterior and posterior margin of the external naris. However, “posterior process of the premaxilla” typically refers to the portion extending posteriorly along the dorsal surface of the rostrum between the maxillae. I think the authors should come up with a different term for these projections along the narial border. It would also make discussion of these features later in the text clearer.

Line 221: please give the specimen number for the “Chinese teleosauroid”

Line 223: I think a semicolon is missing after the word “nares”

Line 225: Is the pronounced lateral expansion of the premaxilla is really autapomorphic for this taxon? Platysuchus and the Chinese teleosauroid also have laterally expanded premaxillae (the authors even note in the discussion that a laterally expanded premaxilla is shared by Bathysuchus, Platysuchus, Mycterosuchus, and the Chinese and Thai teleosauroids).

Line 227: missing a comma following “brevior”

Lines 231-232: Are the ornamentation patterns really autapomorphic? If so, how do they differ from other taxa with lightly ornamented maxillae (e.g. Aeolodon, Chinese and Thai forms)?

Line 262: as mentioned above, I’m not sure this MNHNL specimen is actually Platysuchus

Line 263: The specimen number listed for T. cadomensis is of a specimen lacking a snout, so this should probably not be given as evidence for 5 premaxillary teeth.

Lines 273-274: “Overall the external nares constitute a small length of the entire premaxillae that develop posteriorly for more than 67% of its entire length” - I’m not exactly sure what this statement means. Are the authors talking about the posterior process of the premax in relation to the anteroposterior length of the naris in dorsal view? This doesn't seem like a reliable measurement given deformation... If they're referring to something else, this should be made clearer. Based on how this is worded in the diagnosis, I guess what they mean is that the portion of the premaxilla posterior to the external nares is 67% of the total length of the premax?

Line 276: “projections of the premaxillae in anterior and dorsal direction” – similar to the diagnosis, I think the authors should modify how they are describing these processes on the anterior and posterior margin of the naris. Perhaps describing each process individually would alleviate the confusion.

Lines 277-278: “anterior margin of the external nares… ornamented by fine ridges” – Based on Fig. 3E, it looks like these ridges are along the anterior margin of the premaxilla (above alveoli), rather than along the anterior rim of the naris. This also seems to be a common feature of many teleosauroids (e.g. similar ridges are visible in “S.” heberti and Lemmysuchus).

Line 284: “premaxilla” should be “premaxillae”

Line 286: the word “was” is unnecessary

Line 287: “horizontal (square-shaped) profile…” - here, a line interpretation, or sutures drawn over the images would help. Also, "horizontal" doesn't really describe the shape of this suture well. The maxillae send anterior processes between the palatal processes of the premaxillae. The anterior margin of the suture may be horizontal, but the overall suture must be U-shaped (with a straight anterior margin), or something like that.

Lines 289-290: on the weak ornamentation of the premaxilla – It seems to me that most teleosauroids lack pronounced ornamentation on the premaxilla, with M. nasutus being an outlier.

Line 292: I don’t think the parenthetical “s” in “suture(s)” is really necessary. It is safe to assume the maxillae contact more than one element.

Lines 300-301: on the statement that M. nasutus, A. priscus, and Platysuchus are the closest relatives of Bathysuchus – based on the phylogeny presented in this paper, A. priscus is not closely related to Bathysuchus.

Lines 304-306: “snout length is a plastic feature… independently diverged towards extreme longirostrine or mesorostrine/brevirostrine morphologies (see Discussion)” – I don’t see the topic of snout length evolution anywhere in the Discussion section. Either this should be added (which could be interesting), or this reference to the Discussion should be removed.

Line 317: the word “of” is missing following “most”

Lines 318-319: “spacing is as wide as adjacent alveolar length or more” – In the diagnosis, the authors state this spacing is “longer than adjacent alveoli”. I don’t know which of these statements is accurate, but they should match.

Line 324: “beginning of the posterior end of the snout” – How are the authors defining the posterior end of the snout? The anterior margin of the orbit?

Lines 324-325: “…roughly corresponding to the M27-M30 alveoli” – the authors should note somewhere (possibly near the beginning of this paragraph) that the Quercy specimen is missing the posterior-most alveoli and that M30 does not correspond to the end of the tooth row. Prior to looking at the figure in Vignaud et al., I thought this was saying that the tooth row ended 5 cm anterior to the posterior end of the snout (because it is stated that the specimen has ~30 maxillary alveoli), which obviously would be very odd.

Line 336: “guilds” should be “guild”; “as well as” should be “along with”

Lines 345-346: “medial keel that is not present in the other two osteoderms” – It appears the other dorsal osteoderm is broken, missing the lateral(?) edge. Is it possible the keel would have been on this broken portion? Presence or absence of keels is pretty variable in teleosauroids (even along an individual osteoderm series), so it’s hard to make an argument based on phylogeny. Also, that the inferred ventral osteoderm lacks a keel isn’t surprising. I don’t know of any keeled ventral osteoderms.

Lines 354-362: There is a lot of seemingly unnecessary background info about the matrix presented here. I think this paragraph could be cut down substantially as the important information about the matrix is in the following paragraph.

Line 371: “OUT” should be “OTU"; also, please include the specimen number for the Chinese teleosauroid.

Lines 377-394: please include information about which collapsing rule was enforced in TNT somewhere in this paragraph.

Line 397: “H+Y phylogenetic analysis” – This is a trivial point, but I’m not sure it’s necessary to refer to this as “H+Y” since the authors aren’t using any other datasets in this paper (unlike in other papers where they use multiple datasets and referring to them by name makes more sense)

Line 410: “continued to be in a stable…” – I’m not sure what this means.

Lines 417-418: “Postosuchus kirkpatricki lies outside the clade that unites all other taxa…” – I don’t think this is worth mentioning as this relationship is forced by designating this taxon as the outgroup and is not really a result of the analysis.

Line 423: the word “both” is repeated twice in this sentence.

Line 455: “location” should be “locate”

Line 456: “anteroposterior” should be “anteroposteriorly”

Lines 480-482: sorry to keep harping on this number of premaxillary teeth issue, but the published literature isn’t great on this. If the authors have observed 5 premaxillary alveoli in the holotype of Platysuchus, maybe they could note this as a “personal observation”? As for T. cadomensis, this also seem contentious. I don’t have access to Lamouroux 1820, but Westphal 1961 doesn’t seem to mention the number of premax teeth. Westphal 1962 does say 5, but Vignaud 1995 says 4… Is there a specimen number that could be linked with this observation?

Lines 483-485: on the distribution of premaxillary alveoli in M. nasutus – I am unfamiliar with this specimen (NHMUK PV R 3577). I thought the holotype was the only M. nasutus specimen at NHMUK (though I’m probably wrong given who the authors of this paper are and their familiarity with the NHMUK collections). However, the holotype doesn’t preserve the anterior portion of the premaxilla. Has this specimen been published as Mycterosuchus anywhere?

Lines 486-489: on the presence/absence of the processes of the narial border among teleosaurids – I think these projections have a more complex distribution than is described here. The process on the anterior margin seems common (to a greater or lesser degree) to most 3D preserved teleosauroids (e.g. S. heberti, S. brevior; S. bollensis [the less crushed ones]; M. buffetauti); a small posterior border projection is present in the Chinese teleosauroid (and the anterior margin of the naris is poorly preserved, so it is unclear whether it had an anterior projection or not); the anterior projection is also present in the Thai teleosauroids that I’ve seen (though I'm not sure about the specimens the authors looked at).

Lines 493-496: on the presence of ventrally deflected premaxillae in the Chinese teleosauroid and Platysuchus - seems hard to say for Chinese specimen (probably deformed in this region, but the premaxillary alveoli are in line with the maxillary alveoli); both Platysuchus specimens (SMNS holotype and UH specimen) are dorsoventrally crushed, so the actual ventral deflection is hard to estimate (and in general, this is an issue for most teleosaurs that have been crushed...) – though I think there is real variation here.

Lines 497-498: on the direction of the external nares in teleosauroids – this feature is, in my opinion, highly influenced by dorsoventral compression (i.e., the crushing lowers the posterior margin in line with the anterior margin, making the naris appear dorsally oriented). In all 3D preserved teleosauroids of which I’m aware, the nares face anteriorly/anterodorsally. There may be a subtle distinction between anterior and anterodorsal, but I don’t know of any that I would say are dorsally directed.

Line 517: I think “strongly” is probably too strong of a word for describing the ornamentation of most teleosaur snouts. Slight grooves seem like the most common ornamentation among teleosauroids, though Bathysuchus may be less ornamented than average.

Line 521: “thoracic osteoderms of B. megarhinus are not keeled” – this statement is based on a single damaged thoracic osteoderm. Maybe the authors could show a side-by side comparison of the Bathysuchus osteoderm with an Aeolodon osteoderm to help demonstrate the differences?

Lines 526-529: the linking of reduced dermatocranial ornamentation to a pelagic lifestyle – I don’t have an issue with making this connection and it fits nicely with the occurrence of this taxon in deeper water depositional settings. In the diagnosis the authors note that an “inconspicuously ornamented maxilla dorsal surface” is shared with Aoelodon (another putatively more pelagic teleosaurid. However, this is also shared with the Chinese and Thai teleosauroids, both of which come from freshwater fluvial/lacustrine environments, where a pelagic adaptation doesn’t seem a likely explanation. Again, I think the interpretation of reduced ornamentation on the cranium and osteoderms of Bathysuchus as an adaptation for a more pelagic lifestyle is appropriate and important for the authors to emphasize, but they should also note the discrepancy of the occurrence of reduced ornamentation in what would presumably have been the least pelagic of teleosauroids (based on habitat).

Lines 534-535: “reduce the size and thickness of their osteoderms, as well as lose or heavily reduce their ornamentation” – neither taxon actually lose ornamentation altogether (right? I haven’t seen the Frenche A. priscus specimen). Also, I don't believe the authors discussed reduction in size or thickness of B. megarhinus osteoderms in the description. They should add a line or two about this to the description.

Line 537: on the small osteoderms and short tibiae of A. priscus – have these features been discussed in any publications? If not, maybe the authors could include some values (e.g. tibia vs femur length, or something like that), or comparisons with other taxa.

Line 538: on the forelimb of A. priscus becoming flipper-like - are they proportionally shorter or more reduced than other later teleosaurids like S. leedsi or S. durobrivensis (both of which have reduced forelimbs relative to earlier taxa - See Wilberg 2015, but ignore the erroneous placement of Pelagosaurus as a teleosaurid... d’oh)

Line 541: on Brachysuchus coming from deep-water ecosystems – not really important since the two British specimens are from deep-water deposits, but did the Quercy specimen also come from an inferred deep-water deposit?
Line 550: maybe include the Pierce et al (2009) citation for the hypothesis that B. megarhinus was a subjective synonym of S. leedsi here.

Lines 553-554: “B. megarhinus had evolved a pelagic lifestyle” – maybe “more pelagic” would be a better term here. While Brachysuchus has some features suggestive of a more pelagic lifestyle than other teleosauroids, these features don’t come close to approaching the pelagic adaptations of metriorhynchoids.

Comments on figures:
** It looks like most of my issues with the figures were related to the “auto gamma correction” used for the reviewing manuscript – the original image files look much better.
Fig. 2:
-	I feel that parts E and F should be rotated 90 degrees so the dorsal surface is oriented up and ventral down.
-	I also feel this figure could be greatly improved by either adding line interpretations (for dorsal, ventral, and one of the lateral views), or at least highlighting which portions of the specimen have been reconstructed.
-	I also think it would help for the authors to include a close-up view of the ventral surface of the premaxillae as the premaxillary tooth count and alveolar arrangement are important diagnostic characters referenced often in the text.
Fig. 2 caption: “premaxilla” should be “premaxillae”

Fig. 3:
-	This figure would also benefit from either line interpretations or drawing inferred sutures on the photographs themselves.
-	Part E should be rotated 90 degrees as recommended for fig. 2
-	Part C – is the p5 alveolus visible on this specimen? Again, line interpretations would help.

Fig. 5 caption: E and F are identified as “?ventral” osteoderms, but in the text this is definitively identified as ventral.

Fig. 6:
-	What is the dashed branch leading to “Sphenosuchians”? I’m assuming this is a stand in for a paraphyletic grade. This should be noted in the figure caption.
-	The clade labeled “Crocodyliformes” should be “Metasuchia” (Crocodyliformes would be the node bounding this clade + Thalattosuchia & Eopneumatosuchus)
-	There is an aberrant apostrophe preceding “Chinese teleosauroid” in both parts A and B


Instruction: You are one of the reviewers, your task is to write a review for the article. You will be given the title of the article, the number of the round in which the article is located, and your order among the reviewers.

Input:
Title: REVISION OF THE LATE JURASSIC DEEP-WATER TELEOSAUROID CROCODYLOMORPH TELEOSAURUS MEGARHINUS HULKE, 1871 AND EVIDENCE OF PELAGIC ADAPTATIONS IN TELEOSAUROIDEA
Review round: 1
Reviewer: 3

Output:
Basic reporting: The paper provides a revision of the teleosauroid species T. megarhinus, providing new material. The original material is poor (an anterior portion of a snout), and the new material is also poor (an anterior extremity of a snout). The authors consider that T. megarhinus is a valide species and erect a new genus name.
The description is good and well itemized.
Experimental design: 'no comment'
Validity of the findings: If the description is good and well itemized, I strongly disagree with the characters used in the diagnosis as with some from the comparison. I agree that T. megarhinus is probably a valid species, supported by some characters, but these characters are fewer that suggested in the paper. Most of those used to diagnose the new genus are not clear and disputable (I discus that in detail below). They can be found in many thalattosuchians. Most of them are related to the shape of the anterior part of the snout, but this part is often strongly deformed in most of the thalatosuchians specimens and this strongly influence our interpretation of the character. This deformation has not been considered in the paper while it is often strong in thalattosuchians (in particular in specimens from Oxford Clay (Vignaud, 1995)). The specimens presented here are also deformed. If some characters suggest the validity of the species, I think that erect a new genus name is too daring. First, it is mainly based on two fragments of anterior extremity of two snouts (it was not possible to provide comparison with a lost complete French skull), and second, the teleosauroid phylogeny is particularly unclear, and the relationships of T. megarhinus could strongly varies in the future, the poor preservation of the remains (only anterior portion of snout) will probably increase this instability.
The result of the phylogenetic analysis and relationships of B. megarhinus should be presented with more carful du to the poorness of the specimens.
I invite the authors to develop and precise the morphological points I discussed below to eliminate all possible doubt (as mine).
I detailed my comments on the morphology in the pdf file.

The authors also discussed a possible pelagic adaptation in Teleosauroidea based on the reduced ornamentation in B. megarhinus. The ornamentation is weak in almost all longirostrine Crocodylomorphs, in particular in the snout area. Poor or no ornamentation is seen in S. pictaviensis (Vignaud, 1998), S. durobrivensis, S. heberti, S. larteti.
Ornamentation of osteoderms with widely separated pits is also observed in T. cadomensis. The observation in B. megarhinus is based on a unique incomplete osteoderm. Some degrees of variation exists in the ornamentation of the osteoderms within the same species, and some time within the same individual, and the distance between the pits increases with the age (see Mueller-Töwe, 2006; Vignaud, 1998)(CF. German S. bollensis).
I am not sure that the difference in the ornamentation of the snout (maxilla) and osteoderms between teleosauroids indicate more pelagic adaptation in some species of the group, I think the differences are too weak.
Additional comments: No additional comments


Instruction: You are one of the reviewers, your task is to write a review for the article. You will be given the title of the article, the number of the round in which the article is located, and your order among the reviewers.

Input:
Title: REVISION OF THE LATE JURASSIC DEEP-WATER TELEOSAUROID CROCODYLOMORPH TELEOSAURUS MEGARHINUS HULKE, 1871 AND EVIDENCE OF PELAGIC ADAPTATIONS IN TELEOSAUROIDEA
Review round: 2
Reviewer: 1

Output:
Basic reporting: no comment
Experimental design: no comment
Validity of the findings: no comment
Additional comments: Comments on the manuscript “A revision of the deep-water teleosauroid crocodylomorph Teleosaurus megarhinus Hulke, 1871 and evidence of pelagic adaptations in Teleosauroidea”.

I review the first version of the present paper and the authors consistently increased the quality of the paper. They answer to many of the comments I provided in my first review, and bring a particularly interesting analysis on the postcranial morphometry of teleosauroids and their possible adaptation to pelagic environment.
I still have some comments and disagreements, not on the characters, but on the interpretation of some of them in some crushed specimens.

Detailled comments

Diagnosis: “the premaxillae have five alveoli (shared with Platysuchus multiscrobiculatus Berckhemer, 1929, Teleosaurus cadomensis Lamouroux, 1820)”: 5 shared with a number of other teleosauroids.: shared with other thalattosuchians such as in S. deslongchampsianus from Kimmeridgian of France, and S. priscus from Germany (See Godefroit et al., 1995). They also must be cited, considering the provided diagnosis, only Platysuchus multiscrobiculatus and Teleosaurus cadomensis share the presence of 5 pmx teeth.

“in dorsal view the external nares have an ‘8’ shape, created by the enlarged anterior and posterior projections of the of the premaxilla (shared with Mycterosuchus nasutus);”: We agree that the anterior projection of the premaxilla is present in many teleosauroids. Yet this is not the unique feature that contribute to give the external nares a ‘8’-shape. Furthermore our new comparative figures show an array of teleosauroids and demonstrate that only a restrict sub-set has ‘8’-shape external nares. We agree that this is not a unique feature of Bathysuchus. The impact of preservation on this character has also been carefully considered. Even in dorsoventrally flattened skulls all these characters can still be confidently assessed in the majority of cases where the whole snout is preserved.”: OK, but it is also probably shared with T. cadomensis (see Eudes-Deslongchamps, 1870; Brignon, 2014) and S. megistorhynchus (see Godefroit et al., 1995).

“created by the enlarged anterior and posterior projections of the of the premaxilla”

“reduced antroposterior length of the external nares”: anteroposterior

“more than 67% of the premaxillae total length is posterior to the external nares [shared with ‘Steneosaurus’ gracilirostris Westphal, 1961 and the Chinese teleosauroid (IVPP V 10098)];” : Also in T. cadomensis (68%), S. megistorhynchus (80%), S. brevior (80%), P. multiscrobiculatus (69%), S. obtusidens (68%, from fig from Andrews), and probably S. larteti.

P14: “in fact, the P1 and P2 alveoli are laterally aligned, but are also well-separated.”: If the authors consider that the alveoli are not nearly confluent as observed in S. leedsi and S. edwardsi, it cannot be said that they are well separated. Moreover, the difference between both character states is weak, and I am not sure that the separation between P1 and P2 differs significantly between cited species.

P15: “Yet, it is noticeably more extreme in Bathysuchus megarhinus than in the other taxa. It is possible that this condition has been slightly exaggerated by the preservation of the specimens. However, we see no reason why a dorsoventral compaction would result in moving the premaxillae downwards rather than buckling it on the same level as the maxillae”: Lateral expansion and ventral deflection of the pmx: we agree and acknowledge that the pmx is laterally expanded in other teleosaurid. However we added a comparative table to show that the extent of the lateral expansion of the pmx is particularly exaggerated in Bathysuchus specimens. Similarly for the ventral deflection. We added further discussion and comparisons for both these characters”: The problem is not that the ventral deflection is exaggerated by dorsoventral flattening in B. megarhinus (I agree with the authors), it is that the ventral deflection could be decreased by this flattening in other species for which the specimens are strongly flattened. It is the case in many species. I agree with the authors that the ventral deflection is probably stronger in B. megarhinus, but this character is difficult to evaluate (and thus to compare) in many teleosauroid species.


Instruction: You are one of the reviewers, your task is to write a review for the article. You will be given the title of the article, the number of the round in which the article is located, and your order among the reviewers.

Input:
Title: SPATIAL VARIATION IN ALLOMETRIC GROWTH OF INVASIVE LIONFISH HAS MANAGEMENT IMPLICATIONS
Review round: 1
Reviewer: 1

Output:
Basic reporting: The word choice needs to be consistent throughout the paper when referring to various items (see below). The word "major" is a subjective term and not appropriate to use in this manuscript. There is not a test for major or non"majorness", rather let the reader decide what is major.  There are a few other word choice comments or clarity questions that I have, see below.

L 19: Using the word “major” is a subjective word and elicits an emotional response usually in those that read it. Please choose a less loaded word. Major to one person is not necessarily major to all people. Instead use substantial, significant, etc. Please make the appropriate changes throughout the manuscript as well ( results L142; discussion: L 175).
Introduction:
Line (L) 23: Capitalized “western” as was written in the Abstract and insert Ocean after “Atlantic”. As it reads now it sounds like the Atlantic Sea.
L24: replace “liberation” with “release”.
L 37: Albins and Hixon (2008) did their research in the Bahamas not Florida. Please correct.
L47: Replace impacts with “negative effects”.
L61: replace “know” with “known”.
Fig 1. To stay consistent throughout the manuscript please refer to the general region of the Atlantic ocean the same way. Throughout the manuscript it is referred to as the Wester Atlantic, North Atlantic, North-Western Atlantic. Choose one way to refer to this throughout all text and figures (see lines: 11, 23, 23, 81, 145 158). Not sure I found them all.

Methods:
L 82: The Bahamas are actually part of the Western Atlantic Ocean, not the Caribbean, please update your sample sizes.

L 115: You changed how you refer to grams, here you use (gr) where as you used (g) before (see lines 100, 113). For all references to grams, both in the text and figures, please use (g).

L 121: It is not clear to me what the TL ϵ (34,310) means. Can you re-write or clarify what is meant by this?

L125: Will you add the github URL so the readers can find the data and code. It was not clear where the raw data would be shared either.

Results:
L 134-135: Did you use all of the “different pairs of parameters” from all of the studies individually? Do I understand the right? If so can you adjust the words to be “each of the different pairs of parameters”?

L 134-135: It is not clear what you mean by the lowest and highest weight estimates. For what size did you estimate these? These are pretty low weights so It must have been a small length, why just do it for a small length? Would you assume the effect to be the same among at all lengths? I suspect not with the exponential relationship.

Fig. 3. Why are there two solid light green lines for the Sabido-Itza et al. 2016b? IN the legend for sex make sure that there are two dashed lines for female not just one short dashed line.

Fig. 4. In the caption please indicate what “BC” and “PNAX” mean for the Sabido-Itza 2016b refer to. It is not clear to the reader.

Discussion:
L 152: The phrase “variation is related to space” does not really say much. What do you mean by related to space? Do you mean that the is spatial heterogeneity in the parameters?

L 152: I am not sure what word you mean to use when you said: “we shot that”. Please choose a different word.
Experimental design: L 82-92: The authors do a good job indicating many of the differences among the studies, I wonder about the time of year, which might have a large effect on lionfish growth. One would expect both temperature and food availability to change. What time of year were these collected?

L 92-94: Why include the Fogg et al. (2013) data when you already know that it is likely to underestimate the weight due to the use of spineless weight. What effect did this have on the analysis using data that you know to be different than the other data? Interestingly, Fig. 3 shows that the Fogg data has some of the largest weights-at-length, not the smallest.
Validity of the findings: L 107-108: There appear to be quite a few differences in the sampling and processing methods among all of the studies (lines 82-92). Which the authors rightly discuss and support the conclusion that using local in situ, not ex situ parameters are critical to use. However, I wonder how this affects the data analysis. To use an ordinary least squares regression when all of the locations and study methods are likely to have an effect does not seem appropriate. I suggest using a mixed modeling technique with "study" as a random effect and the other parameters from equation (3) as the fixed effects, so running a LMM. If the error is not normal, as I suspect because you used a standard error correction you could then use a GLMM with a Gamma error distribution since the response variables are continuous and strictly positive. Doing this type of analysis would allow you to talk more specifically about the amount of variation the occurs based on the ex situ parameters to a site.

L175: Remove the word major from the main conclusion. Use either key, central, or fundamental. Major seems to be too strong and subjective of a word.
Additional comments: Overall this study is a nice review of the existing data on allometric growth of lionfish. I like using new data as a case study to show local and regional differences and highlights the need to collect data at the local level to understand how this invasion manifest across the invaded region. I am interested to see how using a different statistical test might be able to shed some light on what the actual variation is among sights and using a mixed-model method should help you estimate this.


Instruction: You are one of the reviewers, your task is to write a review for the article. You will be given the title of the article, the number of the round in which the article is located, and your order among the reviewers.

Input:
Title: SPATIAL VARIATION IN ALLOMETRIC GROWTH OF INVASIVE LIONFISH HAS MANAGEMENT IMPLICATIONS
Review round: 1
Reviewer: 2

Output:
Basic reporting: See attached letter
Experimental design: See attached letter
Validity of the findings: See attached letter
Additional comments: See attached letter


Instruction: You are one of the reviewers, your task is to write a review for the article. You will be given the title of the article, the number of the round in which the article is located, and your order among the reviewers.

Input:
Title: SPATIAL VARIATION IN ALLOMETRIC GROWTH OF INVASIVE LIONFISH HAS MANAGEMENT IMPLICATIONS
Review round: 2
Reviewer: 1

Output:
Basic reporting: Line (L) 26: The word “invasive” is redundant with the previous sentence. There are only invasive populations at these locations as indicated in the previous sentence.

L 36: delete the word “establishment”

L 140: The standard deviation reported is quite large, and would have a lower end stretch into the negative numbers. I assume this was because of the many small lionfish and few of the larger ones that were collected. Is this why the heteroskedastic-robust standard error correction from Zeileis (2004) (L 109) was used? If so can you indicate this around line 109?

L 153-156: Because the Bahamas are in the Western Atlantic (as indicated in Fig. 3), it is inaccurate to say, “ that weight ratios for the central Mexican Caribbean different from those obtained from the Western Atlantic” (L153-154), but “ratios did not differ” from the Bahamas (L156). Please adjust the wording.

L 165: Because this study did not evaluate directly different management practices I would adjust the wording to, “and that this variation may be relevant for managing invasions.”

L 182: I suggest switching the word “space” to “location”, which I think is more accurate for what the authors mean.

L190: I suggest changing “points in time” to “times of the year” to more specifically suggest seasonality in growth rates
Experimental design: Figure 3/Figure 5. There appears to be a potential separation in the allometric models between the northern sites GoM/WA and CA, albeit there is one CA site that appears to cluster with the GoM/WA, from one of the locations by Sabido-Itza (2016).  (1) Did you look at all into clustering at a regional level instead of local and see how that would affect your predictions? Are the northern sites different than the Southern sites? Would this regional level be useful to use for management? (2) was there anything unusual about the sites for the Sabido-Itza (2016) sites that cluster closer to the GoM/WA, such as depth? I only bring this up because of what Bentacur-R  et al. (2011) found with a Northern and Caribbean group difference from mitochondria DNA.  If there is a difference that this study could report, it would be a documented phenotypic difference matching a mitochondria difference, which would be an important finding to report. I think it is worth looking into this to strengthen the results and potential impact of this manuscript.

To do this in a simple way, you could look at the order shown in Fig 5 and see how likely this order is by random chance, to cluster based on regional level. If you randomize the order of the local sites 1,000 or 10,000 times, then look at the number of times that you had this clustering at the regional level or more extreme.
Validity of the findings: no comment
Additional comments: Overall, the Authors greatly improved the manuscript and addressed all the comments very well. The take-home message that heterogeneity of lionfish growth within the invaded range is important to document, especially for management purposes and local adaptation. The authors do a good job of presenting their data and conclusions. Below are a few minor comments that should be addressed before the manuscript is published, but the manuscript is very close and is well written and presented. I know it might be a bit more work to address the comment about the data present in Fig 3/ Fig 5, but as a fellow lionfish research and interested in how this invasion has progressed, it should be looked at and hopefully without too much work.


Instruction: You are one of the reviewers, your task is to write a review for the article. You will be given the title of the article, the number of the round in which the article is located, and your order among the reviewers.

Input:
Title: SPATIAL VARIATION IN ALLOMETRIC GROWTH OF INVASIVE LIONFISH HAS MANAGEMENT IMPLICATIONS
Review round: 2
Reviewer: 2

Output:
Basic reporting: The authors have clarified the language in their submission to meet the requests of the reviewers.
Experimental design: The authors have made the necessary changes to the analysis and presentation of their findings based on the reviewer suggestions.
Validity of the findings: The findings are valid and the data are robust.  The contribution to the field is supported by their data.
Additional comments: Thank you for your thorough responses to each of the reviewer recommendations.  The paper is much improved.


Instruction: You are one of the reviewers, your task is to write a review for the article. You will be given the title of the article, the number of the round in which the article is located, and your order among the reviewers.

Input:
Title: EPIZOOTIC ULCERATIVE SYNDROME CAUSES CUTANEOUS DYSBACTERIOSIS IN HYBRID SNAKEHEAD (CHANNA MACULATA♀ × CHANNA ARGUS♂)
Review round: 1
Reviewer: 1

Output:
Basic reporting: Clear and unambiguous, professional English used throughout.
 --> The primary manuscript yes, the animal protocols no
 --> Animal protocols and approval are not in English, I’m not familiar with PeerJ’s official regulations, but it would be good to have it translated.

Literature references, sufficient field background/context provided.
--> The problem of EUS is well documented and defined in the introduction. Understanding secondary infections and disease susceptibility in a host is a very important part of medical microbiology. Further, few research studies have been conducted looking at microbial changes in a host while infected with a eukaryotic parasite.

Professional article structure, figs, tables. Raw data shared.
--> Raw data has not been made publically available
Experimental design: Original primary research within Aims and Scope of the journal
--> Yes

Research question well defined, relevant & meaningful. It is stated how research fills an identified knowledge gap.
--> Yes

Rigorous investigation performed to a high technical & ethical standard.
Methods described with sufficient detail & information to replicate.
--> No, see below
#Sampling methodology Line 86-106
 It is not clear how infected fish were obtained. Were fish inoculated with an infectious dose and if so how much? Were fish just picked from the pond and separated into healthy vs sick? Were there various levels of infection rate among the fish? Line 90-91 states “
90 Five fish of each type were collected, and their body weight, body length, and area of ulceration were measured prior to collecting cutaneous microbiota samples.”
 Line 94: what is the justification of washing off the mucus prior to sequencing… many of the protective microbes likely will be removed by this procedure
 Where are the results for fungal and bacterial isolates… Line 98-fungal pathogen ID, Line 97-bacteria culturing

#Histopathological analysis, Line 107-116
 It is fantastic that the authors are doing histopathology analysis on their samples, but there is no mention as to what they have actually done (measured). Also, there is no mention of statistics used to indicate disease state

#Pathogen ID Line 117-133
 does the author describe rates of disease ?
#Microbiome analysis Line 133 – 164
 How many samples were actually sequenced…and were there appropriate negative and positive controls included? Line 134-138 does not mentioned sample numbers
 There are many other citations to using this 16S rRNA region, you should cite the other original papers rather than just your labs, Line 141
 Using 97% OTU picking is no longer the best method for doing OTU picking as it has been replaced with ‘exact-sequence-variant’ procedures. Examples include dada-2 and deblur. Line 155
 Line 157-158, the MANOVA test can only be used on normal-distributed data, it is NOT non-parametric. You may use the Kruskal-wallis test as a means to compare categorical data and is essentially the ‘non-parametric anova’ test. The PERMANOVA, which is what you reference in that citation is a non-parametric statistic which can be used on non-normal data. Also, it is not appropriate to pull out individual taxa and compare against other taxa from other groups (figure 2b). There are a variety of methods out there which mostly involve log-ratio comparisons

Methods described in with sufficient detail
--> for the most part yes, although there are some discrepancies which need to be addressed and are described in previous section
Validity of the findings: Impact and novelty not assessed. Negative/inconclusive results accepted. Meaningful replication encouraged where rationale & benefit to literature is clearly stated.
Data is robust, statistically sound, & controlled.

--> Some of the statistical measures used are no longer acceptable to microbiome research and thus should be recalculated using appropriate methods. For instance, due to the compositional nature of microbiome data, it is almost always non-parametric, thus using parametric statistics is not appropriate.
--> Line 171-172, is there a way to better describe (descriptive statistics) the level and types of ulceration statistically?
-->Line 176-177, To quantify bacterial growth on the skin you compare OD readings, which is fine. You could in addition compare the 16S copy numbers or a single copy gene of the actual samples to quantify overall microbial density amongst the two groups (healthy vs disease)
-->Line 181, Did you process samples from both health and diseased fish and show relative concentrations of the Aphanomyces amplicon across these sample groups? Figure 1C only shows that you tested presumably 4 samples, whereas you describe sampling 20 for comparisons in Table 1 and 10 for the microbiome. Please provide all of the data including if Aphanomyces was at all detected on the healthy fish. Alternatively, do qPCR to show relative concentrations in the two groups.
-->Line 187, How did you determine your rarefraction depth – this seems random. Did you include controls and if so what were their read counts?
-->Line 200-226, please repeat the analysis using appropriate statistical measures as commented on in the methods section. Note, the LEfSe is appropriate but you do not mention it in your methods.
-->Line 212, You use the LEfSe method to do differential abundances but you don’t describe this in your methods section…
-->Line 224-226, This is a very interesting finding/observation, but you do not actually test this with statistics. You should calculate the actual beta-diversity distances of each grouping (healthy vs sediment, healthy vs water, disease vs sediment… etc) and then compare the overall similarities to test your observation. Currently, the network analysis does not do this statistically. Your PCA plots in figure 3 provide some support for this, but again is not tested. Also, it would be better to use weighted and unweighted unifrac distances which takes into account the phylogenetic distances of microbes in samples followed by a PCoA visualization. There are many inherent problems with visualizing microbiome data when comparisons are made using Euclidean distances.

Conclusion are well stated, linked to original research question & limited to supporting results.

--> The authors conclude that upon Aphanomyces infection the cutaneous microbiome is perturbed and that furthermore other (presumably secondary) pathogens are enriched which could further cause harm to the fish. The author identifies microbes which are also reduced in this given scenario. The authors do not perform any additional experiments to evaluate and validate that the ‘enriched pathogens’ would actually be pathogenic by Koch’s postulates. They also do not describe any functional aspects such as toxin genes to validate whether these microbes are indeed pathogenic. Since this is the main argument of the study, it would be important to validate. This could be done by whole genome sequencing or targeted PCR of those toxin genes. Further, pathogens could be isolated and cultured and then inoculated onto fish to confirm pathogenesis.
There have been several other microbiome papers associated with this aquaculture important fish species. It would have been nice to see a meta-analysis to understand how these microbes which were abundant fit into the broader context.
Additional comments: No additional comments


Instruction: You are one of the reviewers, your task is to write a review for the article. You will be given the title of the article, the number of the round in which the article is located, and your order among the reviewers.

Input:
Title: EPIZOOTIC ULCERATIVE SYNDROME CAUSES CUTANEOUS DYSBACTERIOSIS IN HYBRID SNAKEHEAD (CHANNA MACULATA♀ × CHANNA ARGUS♂)
Review round: 1
Reviewer: 2

Output:
Basic reporting: The manuscript was well written and with very concise presentation of experimental results.  The authors provided adequate background or overview of the study with references that are relevant to EUS and bacterial infections associated with the syndrome.  The authors clearly stated the hypothesis and the objectives of the study.

Some minor corrections:
list of references:
lines 315-316 - revise the title of the article to be consistent with the format.
line 306 - scientific name should be italicised.
line 402 - ulcerativesyndrome should be ulcerative syndrome
Experimental design: 1. The authors stated in the "Materials and Methods" section that 5 fish each (with EUS and without EUS) were collected, but in Table 1, the sample size for each group was indicated as "10 fish". Perhaps the authors can check this or clarify how they used the 10 fish that were collected (5 each for histopathology and 5 each for microbiome analyses??).

2. The authors collected both hybrid snakehead with EUS and without EUS from one pond, kindly indicate the size of the pond where the fish were collected.  Although the fish were collected on the same day, the environmental factors (eg. water temperature, pH) were reported with standard deviations (+/-). The authors need to clearly state if this was daily variations or if this indicates fluctuations within a specific period of time (eg, week, month).
Validity of the findings: 1. The conclusions were clearly stated and answered the hypothesis posed by the authors. However, the study also presented bacterial composition of pond water and sediments. These data were not addressed in the discussion. Perhaps the authors can indicate the significance of these data in relation to the hypothesis/scope of the study.
Additional comments: No additional comments


Instruction: You are one of the reviewers, your task is to write a review for the article. You will be given the title of the article, the number of the round in which the article is located, and your order among the reviewers.

Input:
Title: MAHALANOBIS DISTANCES AND ECOLOGICAL NICHE MODELLING: CORRECTING A CHI-SQUARED PROBABILITY ERROR
Review round: 1
Reviewer: 1

Output:
Basic reporting: The author proposes a new approach on the use of mahalanobis distance in ecological niche modeling. Niche modeling has been indicated in conservation strategies and there are many methods available and at the same time many uncertainties. This study is important for reducing uncertainties. However, there is no certainty as to which modeling method is most effective and the method consensus approach has been the most indicated. Therefore I thought that in the introduction of this study lacked tacked mentioning what advantages of  malalanobis distance compared to other methods in conservation strategies. Can it be used with species of few occurrences? Can it be used with species of restricted distribution?
Experimental design: The experimental delineation of the article has been understood. However, I suggest performing experiments with different numbers of occurrences to evaluate the performance of the method.
Validity of the findings: The article is important so that the uncertainties in the forecasts are reduced. However, it is necessary to reinforce the importance of using the distance malanobis method for niche modeling and what its main impacts are when used erroneously.
Additional comments: I enjoyed learning from the article on improving a modeling method. Many details can make a difference in the parameterization of niche modeling. I thought was very valid. However, I think the study would be better with simulations with different amounts of occurrences. I would like to know the consequences for species conservation.


Instruction: You are one of the reviewers, your task is to write a review for the article. You will be given the title of the article, the number of the round in which the article is located, and your order among the reviewers.

Input:
Title: MAHALANOBIS DISTANCES AND ECOLOGICAL NICHE MODELLING: CORRECTING A CHI-SQUARED PROBABILITY ERROR
Review round: 1
Reviewer: 2

Output:
Basic reporting: This paper identifies a pervasive little problem in the use of Mahalanobis distances to characterize the niches of species. The paper is concise and well-written, the bug the author identified is real, and potentially damaging. I believe the paper should be published, almost as it is, with the following minor comments:
1)	Figure 2 lacks the first three labels.
2)	In the abstract, the author choice of words suggest that niche modeling is equivalent to resource selection, habitat suitability, or distribution modeling. It should be perfectly obvious that modeling a distribution is not synonymous with modeling the selection of resources, for example. Just change the wording so it is clear that Mahalanobis distances are used in all those fields, without implying that the fields are synonymous.
Experimental design: No comment
Validity of the findings: No comment
Additional comments: No comment


Instruction: You are one of the reviewers, your task is to write a review for the article. You will be given the title of the article, the number of the round in which the article is located, and your order among the reviewers.

Input:
Title: THE KOALA (PHASCOLARCTOS CINEREUS) FAECAL MICROBIOME DIFFERS WITH DIET IN A WILD POPULATION
Review round: 1
Reviewer: 1

Output:
Basic reporting: No comment
Experimental design: What was the spatial separation between the individuals feeding on these two diets? Is it possible that other factors other than diet (climate, microbial availability, etc.) could have contributed to these differences? It is known that spatial microbial dispersal can drive diversity differences: http://www.pnas.org/content/114/52/13768

For alpha diversity, please include collection as a main variable, not as a random effect.

Lines 283 – 292  - another way you could investigate the magnitude of differences between years would be to compare pairwise distance measurements between the two groups. One might expect pairwise distances between groups to be larger in 2013 than in 2015.
Validity of the findings: No comment
Additional comments: Line 95, 129, anywhere else throughout the paper – please make sure to always use “16S rRNA”, not just 16S.
Line 142, 460, anywhere else throughout the paper - the word “This” should typically have a noun after it to make sure it is clear what it refers to.
Line 153 – maybe divide this into two sentences, or change to “so these individuals”
Line 192 – what does this 4% refer to? 4% of total sequences?
Line 197 – change to “abundances”
Line 199 – change to “levels”
Line 242 – seems like a word is missing here. Using an in vitro digestion.. model?
Line 463 – change


Instruction: You are one of the reviewers, your task is to write a review for the article. You will be given the title of the article, the number of the round in which the article is located, and your order among the reviewers.

Input:
Title: THE KOALA (PHASCOLARCTOS CINEREUS) FAECAL MICROBIOME DIFFERS WITH DIET IN A WILD POPULATION
Review round: 1
Reviewer: 2

Output:
Basic reporting: This study contributes to the knowledge about Koala microbiome and its interaction with their diet. Professional English language used throughout.
Some considerations and corrections to the authors:
1)ABSTRACT
1.1 Following Peer J Standards the Abstract section should have Headings structured to be bold and followed by a period. Background. Methods. Results. Discussion. This instruction was not followed and should be corrected.
1.2 The abstract contains only 221 words and could be enriched with results and discussion about beta diversity analysis.
1.3 Are n=32 the faecal bacterial communities or the koalas?
1.4 The term foliage used in the manuscript could be used in the abstract to better describe what part of the food species is consumed.
1.5 Is the dietary pattern of the Koalas a question of “strongly preferred” or availability of the species in the place they live?Describe it better .
1.6 Indicate Permanova tests and results  in the Figures 1, 2 and 3 and also Supplemental figures.
2. Introduction
2.1 The Background  about  Cape Otway and the Koalas provided a very good context to the article, but the information about Eucalyptus leaves chemical composition could be enriched with data from antimicrobial properties of essential oils of Eucalyptus species .
2.2 At line 117, please clarify "they" .
Experimental design: 1.The nutritional quality evaluation of the foliage samples was very simple. No anti nutritional  parameters were evaluated. Explain why.
2.The leaf collection method indicated that Epicormic and adult E. viminalis (n=16) and E. obliqua (n=11) leaves were collected at Cape Otway in September 2013. Was there no collection in 2015? How was food species consumption attributed in 2015? This can impact Diet Composition results for 2015.
3.Explain the rationale of using two methodologies (terminal restriction fragment length polymorphism, and 16S amplicon sequencing) and two different beta diversity analysis (Unifrac for 16S and Bray-Curtis for RFLP) for comparison.
4. Metadata supplied indicates that sex and age characterization of the Koalas are available. Were microbiome data analysed  under these perspectives? Was Permanova performed for theses data?Indicate the results found
5. A supplemental map with detailed GPS location of the koala and the forest patches could be added to.
Validity of the findings: Figure 1 B is missing E obliquoa data. Figure 1A has 13 red dots and Figure 1B only 8. Please correct it.
About Figure 5. 2013 data is complete but 2015 is showing 15 not 18 koalas. Is there a data missing or plot mistake? Is there difference between E. obliquoa diet consumption in 2013 and 2015? Please show the results. This could indicate 3 different diets groups: E. vitamalis, E. obliquoa and Mixed one and could explain differently Figure 1 and 3. Perform Permanova with 3 diets groups.
Figure S3 shows Fungi and Archea data.Results are explained in the Supplemental materials, but it was not possible to find Captions of Figure 3 A and B. It is not clear the year of the data showed.
Lines 312 and 313 indicate results about genus otu levels but indicate figures 3A and B, which have Archea and Fungi data . Please correct it.
Figure S4  is dark and is difficult to visualize data. Please correct it and re upload it.
Review reference indicated at line 379 (Turnbaugh and Gordon 2009b) , as it does not mention the words carnivorous or herbivorous, they talk about lean and obese.
In the discussion authors state "a seemingly subtle dietary change" but the nutritional composition of the two diets are very different. Re - evaluate

Statements at lines 504-510 have no basement in the studied population or data shown. It is a speculation, it would be better in Discussion.
Additional comments: No comment


Instruction: You are one of the reviewers, your task is to write a review for the article. You will be given the title of the article, the number of the round in which the article is located, and your order among the reviewers.

Input:
Title: THE KOALA (PHASCOLARCTOS CINEREUS) FAECAL MICROBIOME DIFFERS WITH DIET IN A WILD POPULATION
Review round: 2
Reviewer: 1

Output:
Basic reporting: No comment
Experimental design: No comment
Validity of the findings: No comment
Additional comments: The authors have done a good job addressing my comments. I have no other issues with the paper


Instruction: You are one of the reviewers, your task is to write a review for the article. You will be given the title of the article, the number of the round in which the article is located, and your order among the reviewers.

Input:
Title: THE KOALA (PHASCOLARCTOS CINEREUS) FAECAL MICROBIOME DIFFERS WITH DIET IN A WILD POPULATION
Review round: 2
Reviewer: 2

Output:
Basic reporting: The author answered well all the questions and performed the necessary alterations.
I would like to mention three small notes:
1)The reference David et al 2014 is referred as David et al 2014 a. I see no need of “a” as there is only one reference from David et al in 2014.
2) Figure S1 and S2 made the places and sampling clearer. However when comparing the identifications placed in the maps and the Koalas identification codes at table S2a it is possible to note absences. The 2015 map is almost complete (17 of 18 koalas), but the 2013 map only shows 6 Koalas. Where is the location of the other 8 koalas, are they together with the other?
3) I am curious about the identification of 4 koalas from 2013. They do not follow codes but “names” (Alf, Beast, Bella, Bilko). Why were they named? Are they wild or not? I think it would be better code them with letters than names
Experimental design: The author answered well all the questions and performed the necessary alterations.
Validity of the findings: The author answered well all the questions and performed the necessary alterations.
Additional comments: I am curious about the identification of 4 koalas from 2013. They do not follow codes but “names” (Alf, Beast, Bella, Bilko). Why were they named? Are they wild or not?


Instruction: You are one of the reviewers, your task is to write a review for the article. You will be given the title of the article, the number of the round in which the article is located, and your order among the reviewers.

Input:
Title: INFLUENCE OF LONG TERM NITROGEN LIMITATION ON LIPID, PROTEIN AND PIGMENT PRODUCTION OF EUGLENA GRACILIS IN PHOTOHETEROTROPHIC CULTURES
Review round: 1
Reviewer: 1

Output:
Basic reporting: The manuscript is well written and covers adequate background knowledge and literature beings reviewed
Experimental design: The experimental design of this study is adequate and addresses the research question raised while also testing the hypotheses made in the introduction
Validity of the findings: no comment
Additional comments: This study looked into the influence of nitrogen depletion on lipid composition and other biochemical components of Euglena gracilis. The manuscript is well written and covers adequate background knowledge and literature beings reviewed. My main concern of this study is the lack of novelty as it has been significantly established in the field of Applied Phycology that nitrogen depletion of cultures results in an increase in the total lipid and TFA content of most microalgae. Similar studies on Euglena has been reported in early work by Garcia Ferris et al., 1996 and Regnault et al., 1995. Nevertheless, an innovative component of this study is the initial growth of Euglena at different N concentration and the effect of the different N concentration during the N depletion period.
Major comments
1)	The author need to better highlight the justification behind this work in terms of large scale TFA and PUFAs production. If the method used in this study had worked and subsequently scaled up, would commercial production facilities first grow the algae and then subsequently starve (deplete) the cells for TFA and PUFAs production. If yes how efficient and cost effective would this be compared to conventional algae cultivation for PUFAs and TFA.

2)	As the authors have discussed in the discussion section, the enhanced production of the carotenoid diadinoxanthin during the N depletion period is the only positive outcome of this work. Is there any commercial potential/ benefits for this carotenoid? If yes it should be highlighted in the introduction and discussions section of this manuscript.

3)	Line 284-286: The authors stathe that exponential growth in all cultures ceased after Day 5 when N was exhausted but in their results section state that N was only exhausted at Day 7 for HN. This is contradicting and will affect the results

Minor Comments
1)	Line 299: Need of proof/reference to support the claim that C is being converted to FA.

2)	Line 219-220: The authors state that the higher N content ‘boosted the growth of the algae’ but did not evaluate the specific growth rate (µ) of the algae in each treatment. I would recommend the authors to calculate the µ based on the increase in biomass of the three treatments and compare them as it would provide additional important information.

3)	The manuscript needs to be proof read to include punctuation and sentence connectors such as commas and other connecting words. Many long sentences are comprised of two or more different statements which are awkwardly combined together
                Example: Line 246-247
                                  Line 232-233 and a few more

4)	Line 251-253: The changes in SAFA, PUFA and MUFA needs to be better explained whether it was changes observed over time or changes between the different treatments.

5)	Figures: There should be some form of indication in the figure to illustrate whether there were any significant difference among the different treatments. You can either use symbols or alphabets on top of each bar chart to highlight significant difference among the treatments

6)	The abbreviations ARA, ALA and EPA needs to be first referred as to its full terminology before the use of the abbreviation for the ease of the readers not familiar with this abbreviations

7)	Chlorophyll a needs to be changed to Chlorophyll a

8)	The values (units) for protein and TFA should be represented as % of biomass rather than mg/g as this is the preferred reporting style of many studies and for ease of comparison with other similar studies.
Based on the questions being raised, I would only recommend the manuscript for publication only after major revision.
Thank you


Instruction: You are one of the reviewers, your task is to write a review for the article. You will be given the title of the article, the number of the round in which the article is located, and your order among the reviewers.

Input:
Title: INFLUENCE OF LONG TERM NITROGEN LIMITATION ON LIPID, PROTEIN AND PIGMENT PRODUCTION OF EUGLENA GRACILIS IN PHOTOHETEROTROPHIC CULTURES
Review round: 1
Reviewer: 2

Output:
Basic reporting: The manuscript is within the scope of the journal and the Introduction adequately introduced.
Experimental design: 1. The authors analyzed three time points of the nitrogen starved Euglena cells grown in photoheterotrophic culture. But they only analyzed the changes of compounds during stationary phase, not in other time points, such as exponential phase. To compare the value with other literature, it is very important to show that they observed similar results to previous reports or not. At this point, it is not clear whether difference between previous reports (such as Regnault et al 1995) and their results came from culture conditions (medium, light intensity and bubbling of CO2) or growth phase.

2. The authors used GC-MS for fatty acid analysis, but GC-MS is not suitable for quantitative analysis, because of difference of ionization tendency for each fatty acid. If the authors want to quantify fatty acids by GC-MS, they have to use standards for each fatty acid molecular specie or change detector to FID (flame ionization detector). If the authors can not do the above analysis, they can focus on comparison of relative amount of each fatty acid species among samples (based on the DW).
Validity of the findings: Data is not robust enough because of the above mentioned issue.
Additional comments: 1. Line 66, spell out TN (total N?).
2. Line 85 and 88, the reference would be (Garcia-Ferris et al., 1996).
3. Line 97, “through” might be “thorough”.
4. Line 120, 1bar would be 2 bars.
5. Line 127, explanation of NH4-N might be needed.
6. Line 191 and 193 “Schimadzu” would be “Shimadzu”.
7. Line 210 and 247, what is TFA (total fatty acid?)?
8. Line 275, “douple” would be “double”.


Instruction: You are one of the reviewers, your task is to write a review for the article. You will be given the title of the article, the number of the round in which the article is located, and your order among the reviewers.

Input:
Title: INFLUENCE OF LONG TERM NITROGEN LIMITATION ON LIPID, PROTEIN AND PIGMENT PRODUCTION OF EUGLENA GRACILIS IN PHOTOHETEROTROPHIC CULTURES
Review round: 2
Reviewer: 1

Output:
Basic reporting: The manuscript is well revised and written. The authors have incorporated most suggestions and answered question asked previously
Experimental design: The experiment is planned and carried out adequately.
Validity of the findings: The results obtained through is robust and statistically sound. The small error margins help confirm this
Additional comments: The authors should mention and discuss in text regarding the statistical difference of parameter they measured (i.e. growth, yield, FA) rather than only including this information in the Figure Caption.

Line 300-301: Could you include the day this happened? “However, the high C: N ratio in stationary phase cultures shows that all cultures were N limited in late stationary phase”.


Instruction: You are one of the reviewers, your task is to write a review for the article. You will be given the title of the article, the number of the round in which the article is located, and your order among the reviewers.

Input:
Title: INFLUENCE OF LONG TERM NITROGEN LIMITATION ON LIPID, PROTEIN AND PIGMENT PRODUCTION OF EUGLENA GRACILIS IN PHOTOHETEROTROPHIC CULTURES
Review round: 2
Reviewer: 2

Output:
Basic reporting: no comment
Experimental design: no comment
Validity of the findings: no comment
Additional comments: This is the second submission of the manuscript “Influence of long term nitrogen limitation on lipid, protein and pigment production of Euglena gracilis in photoheterotrophic cultures” by Tossavainen et al. The authors responded to the reviewers comments mostly. This reviewer has few comments as follow:

1. The authors analyzed three time points of the nitrogen starved Euglena cells grown in photoheterotrophic culture. If this reviewer understand correct, the authors only compared samples from stationary phase, because biomass of the culture is the most abundant in stationary phase and they tried to find out the best time point to have better FAs for nutritional purpose. If this is true, describe it somewhere (maybe in Discussion).

2. The authors used GC-MS for fatty acid analysis, and made standard curves of each FAs using FAME standards for quantification analysis. If the authors did so, it should be written in the text.

3. The FAME standards the authors used does not include 4,7,10,13-hexadecatetraenoic acid (16:4), which is a major FA in Euglena gracilis (more than 10% of total FA). The authors’ analysis is probably missing this PUFA. (see Hulanicka et al 1964 JBC, Constantopoulos et al 1967 JBC, Shibata et al 2018 Front Plant Sci).

4. On line 255, the authors stated that TFA amount is the lowest in the cells grown with HN treatment, even this cells have more chlorophyll a and carotenoids. This reviewer is wondering that HN treatment make the biomass of the cells higher than the cells with other treatments because of higher photosynthetic activity. For photosynthesis, development of thylakoid membrane is necessary and it requires membrane lipid synthesis, which lead to accumulation of FA (attached to the membrane lipids). In this manuscript, C content was not analyzed in detail, so it would be interesting to see how the C content changes (especially photosynthetic activity and accumulation of paramylon) by the treatments they used, in future.

Miscellaneous things:
1. Again, line 85 and 88, the reference would be (Garcia-Ferris et al., 1996), because this paper is written by four authors.

2. Again, line 120, 1bar would be 2 bars, otherwise it is not autoclave.

3. Line 124, 0.02 g L-1 would be 0.02 mg L-1. 0.02 g L-1 is the concentration for the stock solution. If the value authors described is correct, it is 2,000 times higher than the original medium (also check Table 1).

4. Line 198, which is “elution solvent A”?

5. Line 301, there is double periods.


Instruction: You are one of the reviewers, your task is to write a review for the article. You will be given the title of the article, the number of the round in which the article is located, and your order among the reviewers.

Input:
Title: OBSTETRIC AND PERINATAL OUTCOMES OF DIZYGOTIC TWIN PREGNANCIES RESULTING FROM IN VITRO FERTILIZATION VERSUS SPONTANEOUS CONCEPTION: A RETROSPECTIVE STUDY
Review round: 1
Reviewer: 1

Output:
Basic reporting: .
Experimental design: .
Validity of the findings: .
Additional comments: In all, this study is well designed and has addressed an important question. However, I still have the following concerns.

1.	The presentation of the abstract is in chaos. It should be organized logistically and some conjunction words could be used to make the construction clearer. For example: The present study aims to … We found that … In conclusion…

2.	It will be easier to grasp the design of this study if a workflow can be provided. The data of childbirth, twins, fetal reduction, and so on can be presented here.

3.	The diagnosis of dichorionic pregnancy is important in this study. Therefore, how the diagnosis was made should be described in detail.

4.	Please define the complications clearly, including maternal and neonatal complications. For example, how is growth discordance diagnosed?

5.	Please list the specific malformations identified in this study.

6.	The English of this paper is poor. There are plenty of grammatical mistakes in this manuscript, especially in the abstract. Some mistakes are listed as follows.
1)	To address whether the twin pregnancy modes, specifically conceived spontaneously or by In Vitro Fertilization (IVF), is associated with adverse obstetric and perinatal outcomes.
2)	470 dichorionic twin pregnancies were divided on the basis of conception mode: 249 resulted from IVF and 221 were conceived spontaneously.
3)	A higher risk of stillbirth and malformation (4.8% versus 1.4%, P < 0.05) and increased neonatal intensive care unit (NICU) admissions (23.4% versus 12.3%, P < 0.05, respectively) were observed in the IVF-conceived group.
4)	The subjects in this study covers Wenzhou and its surrounding area, South-East Zhejiang province, China.


Instruction: You are one of the reviewers, your task is to write a review for the article. You will be given the title of the article, the number of the round in which the article is located, and your order among the reviewers.

Input:
Title: OBSTETRIC AND PERINATAL OUTCOMES OF DIZYGOTIC TWIN PREGNANCIES RESULTING FROM IN VITRO FERTILIZATION VERSUS SPONTANEOUS CONCEPTION: A RETROSPECTIVE STUDY
Review round: 1
Reviewer: 2

Output:
Basic reporting: The submission is a self-contained study that adheres to PeerJ policies. Raw data are supplied. English editing by a native or professional speaker is advised to ensure that an international audience can clearly understand your text.

The manuscript includes sufficient introduction and background which demonstrate how this study fits into the broader field of knowledge. The relevant prior literature is appropriately referenced.

However, some corrections in presentation of the study aim should be made. The paragraph with the study aim should be rewritten. This paragraph should only comprise the current first two sentences describing the objective. The remaining two sentences (3 and 4) should be transferred to discussion, at the end of the first paragraph, as the explanation of study novelty.

Moreover, currently it is written that “This study is thus designed to assess perinatal and neonatal outcomes of dichorionic twin pregnancies”. However, authors did not mention that the actual study aim was to compare the outcome of naturally conceived twins with IVF conceived ones. Therefore, the aim should be rewritten (This study is thus designed to assess perinatal and neonatal outcomes of dichorionic twin pregnancies conceived naturally or by IVF).
Experimental design: This is an original research. Research question is well defined, relevant and meaningful. Investigation seems to be performed according to high technical and ethical standards. However, the study method is not well presented.

Authors state that a strict selection of examined women was performed. What were the inclusion and exclusion criteria for the study? Were only IFV twins included or did authors consider twins conceived with other forms of assisted reproduction (IUI, ICSI, ET)?

It is not clear what was regarded as gestational age? Did authors mean gestational age at birth? Furthermore, what was considered as “duration of hospitalization”? Was it measured only after delivery, or some women had to be hospitalized prior to delivery due to complications? Please write everything clearly.

Explain with more details the sentence „The medical diagnosis was categorized according to the criteria proposed by Sun et al“. Which diagnoses?

Which perinatal complications were recorded? Which antenatal maternal complications were followed? Authors presented numerous data in the tables which were not at all mentioned in the methods.

How was the outcome of twin pregnancies assessed? What was the main outcome variable in this study and what were the assessed confounding factors? One of the most important negative outcomes seems to be stillbirth as well as having pregnancy-related complications. Outcome measures should be explained in details. Moreover, all analyses should be related to this outcome in particular.

I do understand that most Journals have strict word limitations, but study design and methodology need to be described with sufficient information to be fully understandable and reproducible by other researchers.
Validity of the findings: Data is statistically sound and controlled. However, applied statistical analyses are basic. I would advise authors to perform some more robust analyses (i.e. regression analysis that could test for confounding factors which might influence twin pregnancy outcome, or at least ANOVA or some other analysis depending on study aim).

Tables 1 and 3 should present all p values between groups (just like the Table 2).

Discussion is adequately written.

Conclusions are linked to original research question and based on the obtained results.
Additional comments: This study deals with in interesting and important issue of perinatal and neonatal outcomes of dichorionic twin pregnancies regarding their conception method. Growing interests has been paid to the role of IVF-ET in obstetric and neonatal outcomes of twin pregnancies. Still, as the results of available literature remain to be inconsistent this study is current and relevant.

It is not advisable to start the sentence with the number. Authors should rewrite such sentences in the abstract. These sentences could start with: study included / there were / etc.


Instruction: You are one of the reviewers, your task is to write a review for the article. You will be given the title of the article, the number of the round in which the article is located, and your order among the reviewers.

Input:
Title: OBSTETRIC AND PERINATAL OUTCOMES OF DIZYGOTIC TWIN PREGNANCIES RESULTING FROM IN VITRO FERTILIZATION VERSUS SPONTANEOUS CONCEPTION: A RETROSPECTIVE STUDY
Review round: 1
Reviewer: 3

Output:
Basic reporting: 1.	Let us start with Table 1. The fact that women who have IVF are older than expected and more often have no previous child is well-known and easily explained and lines 139-140 are hardly needed. The authors find a higher rate of “first cesarean section” after IVF than in the control group. If I understand it right can this measure be meaningful only if the woman has at least one previous delivery. If I count it right, there are in the control material 83 women with one or more previous delivery, among which 44 had C-section (53%) while after IVF there are 37 women with one or more previous delivery, among which there are 10 with C-section (27%).  The higher rate in the Table for IVF pregnancies is thus only an expression of the higher rate of first pregnancies. It seems that the difference in the Table just mirrors the obvious fact that the rate of first deliveries in the IVF group is high. This line should be removed, I think.
2.	The difference in mean gestational rate is given as 0.34 day and statistically significant. When expressed in hours, this means 8 hours. Is this difference clinically or biologically meaningful? More important is prematurity. In a large study (Kallen et al., BJOG 2010; 117: 676-682, not quoted by the authors) based on 1545 IVF and 8675 non-IVF dizygotic twins the adjusted odds ratio for <32 weeks was  1.52 (95% CI 1.18-1.97) with week 37-38 as a reference.
3.	Table 2 shows data on maternal conditions. One reaches statistical significance, that is, gestational diabetes. The given p-value, I suppose, is not adjusted for the fact that ten different comparisons have been made. The probability to get one p-value of 0.026 among ten tests is 1-(1-0.026)10 which is not significant. It may anyway be true as an increased risk of various maternal complications has been described by at least some authors.  To this is added that in the present manuscript no adjustment has been made for the fact that for instance age an parity differ between the two groups. I think, therefore, that the authors should state their finding with less emphasis.
4.	Table 3. Here are some matters which should be clarified. As far as I understand, the percentages are counted on the number of twin births, not on the number of twins. This means that one is describing how large chance it is that one or both twins were stillborn or malformed, for instance. If, for instance, both twins were malformed, were they counted as two (and then the denominator should be number of twins, not number of women) or as one (and then the denominator should be number of twin deliveries). I think the latter is the best solution – because of the tie between the two twins, but anyway it has to be clarified how one has counted. Furthermore, I think one should divide the outcome in stillbirths and malformations as these outcomes are very different.  Finally, with such low numbers as in this situation, chi-square should perhaps be replaced by Fischer exact test.  Again no adjustments have been made for the different characteristics of the groups which may contribute to the observed differences.
5.	Generally speaking it is more informative to present odds ratios with 95% CI than percentages and p-values, preferably odds ratios at least adjusted for maternal age and parity. Women undergoing IVF often differ also in other aspects from non-IVF women but I don’t know how relevant these differences are in China, e.g., smoking and BMI.
Minor comments
1. Line 104: Neonatal birth weight – birth weight is always ne0onatal. Change to birthweight. What is meant with “neonatal conversion rate” – do you mean NICU transfer rate?
2.  In some places you write “elder age”, I think “higher age”  or “older age” is to be preferred.
3.  Table 2: Heading. What do you mean with periternal complications? Anyway, I think the listed complications all are maternal.
4. In the Introduction there are statements on a high percentage of twin births after IVF. This was universally true up till the last decade(s) then single-embryo transfer has become the common mode of IVF in some countries. I think this should be pointed out in the Introduction as the comparison between IVF and spontaneous twins is of less interest in that setting- I think the last sentence of the Introduction is a bit exaggerated, considering the relatively small size of the study and its weaknesses, pointed out above. Line 100: what strict selection?
Experimental design: The basic data appear to be all right but above I have pointed out some deficiencies in the analysis of them. The most obvious defect is that no consideration has been taken to confounding factors, notably maternal age and parity.

You found no effect on pregnancy diagnoses (except for gestational diabetes). Have you considered if the numbers are large enough to demonstrate moderate effects? This can be evaluated from odds ratios with confidence intervals.
Validity of the findings: See above. The finding on gestational diabetes may well be random, the effects on stillbirths and malformations should be better presented (preferably with exact malformation diagnoses so the reader can see what has been included).
Additional comments: The English is understandable. I have pointed out some errors which should be changed but an editing of an English-speaking person would be could useful.

It would have been very nice if you in greater detail discussed previous literature. Now you state that results vary and explain it by some general phrases. In what studies were all twins compared, not dizygotic twins? When were the studies large enough to have a power to demonstrate anomalies in pregnancy diagnoses or outcome?


Instruction: You are one of the reviewers, your task is to write a review for the article. You will be given the title of the article, the number of the round in which the article is located, and your order among the reviewers.

Input:
Title: OBSTETRIC AND PERINATAL OUTCOMES OF DIZYGOTIC TWIN PREGNANCIES RESULTING FROM IN VITRO FERTILIZATION VERSUS SPONTANEOUS CONCEPTION: A RETROSPECTIVE STUDY
Review round: 2
Reviewer: 1

Output:
Basic reporting: pass
Experimental design: pass
Validity of the findings: pass
Additional comments: No more comments


Instruction: You are one of the reviewers, your task is to write a review for the article. You will be given the title of the article, the number of the round in which the article is located, and your order among the reviewers.

Input:
Title: OBSTETRIC AND PERINATAL OUTCOMES OF DIZYGOTIC TWIN PREGNANCIES RESULTING FROM IN VITRO FERTILIZATION VERSUS SPONTANEOUS CONCEPTION: A RETROSPECTIVE STUDY
Review round: 2
Reviewer: 2

Output:
Basic reporting: There are a number of sentences which have to be clarified as pointed out in the review.
 Literature references OK.
 Figure OK, Tables need corrections as pointed out in he review. Raw data in Excell.
 Actual hypothesis not stated. All conclusions (except possibly on ICU transfer) uncertain because of low power due to small numbers.
Experimental design: The study is within the scope of the journal.
Research question stated in broad outlines.
No ethical problems but weaknesses in some technical aspects.
In the revised manuscript, most methods used are described but the statistical analysis has some weak points as no consideration to ties between the two infants in a twin pair is taken.
Validity of the findings: Mainly negative results but the relatively small data set makes an absens of a difference uncertain. Actually, there is only one finding of a difference between the two groups which is of some interest, ICU transfer. A detailed analysis of the reasons for this would be welcome.

Some data are not robust, e.g., gestational duration and the concept of malformations, see review!
Additional comments: The authors have made a number of changes in the manuscript and have commented on my referee comments. I think there are still a number of major and minor things to correct before the manuscript can be accepted.
Comments
1.	I pointed out that two “findings”, the higher age and lower parity of women in the IVF group, are self-evident. In spite of this these are listed in the Abstract. I suggest that the sentence starting in line 34 is removed. I am afraid the Abstract will be very thin – the only convincing finding worth mentioning is the increased risk of NICU transfers.
2.	The authors have not taken into consideration my point that a first CS is obviously the case when the delivery is the woman’s first delivery and that IVF women are characterized by having more first deliveries than SC women. A crude comparison as made by the authors of the frequency of first CS is therefore rather meaningless –  when one compares the rate of first CS among women who had at least one previous delivery (and therefore could have had a previous CS), the opposite is found. In their answer the authors say that they have added something to the Discussion on this point, but I cannot find it. The statement that the IVF group has a higher rate of first CS remains (line 159). I suggest this line is removed.
3.	It is now clear that pregnancy duration is determined differently for the two groups: 14 days before embryo transfer in the IVF group and based on LMP for SC women. Actually, the first estimate should take culture time into consideration (2-5 days usually) and the uncertainty of the second estimate is well known – so the small mean difference between IVF and SC is rather meaningless even if it is statistically significant. The Abstract statement of a shorter gestational duration should be removed and in the text the measured difference should be commented on.
4.	After adjustment no difference between the two groups remains with respect to GDM. This is demonstrated in Table 2. I suggest that the column P-value is removed as it can only confuse the reader. In the heading of the Table, I think it is enough to have Adjusted OR, 95%CI and P value. The marginally significant effect on maternal anemia should be commented upon: probably a result of mass significance. – I suggest that you only give a maximum of two decimals. These comments are valid also for Table 3.
5.	In Table 3 it is said that 194 SC had low birth weight and this is 44% which must mean that it is calculated on 442 individuals. This is all right but the statistical comparison with IVF will be   complicated because of the strong tie between the weights of the two twins. Now it does not matter much for most variables, only admission to NICU differs between the groups. Also for this variable there may be a tie but the difference is so large that it can hardly be explained this way.
6.	Table 4 defines stillbirths and malformations. These two outcomes are added in Table 3 in spite of the fact that they are rather different biologically. In the SC column there is actually only one stillbirth and one “cystic mass of chest wall” – if you want to include the third case, neonatal death, you should use the term perinatal death instead of stillbirth. In the list of IVF cases there are four stillbirths – were they in four different twin pairs of in fewer pairs? Again a tie between the twins may complicate analysis. There are two cases of malformations (one cardiac defect, one jejunal atresia). One is a case of papyraceous fetus – is this not a case of early fetal death which should result in exclusion from the study? One case of intraventricular hemorrhage is hardly a stillbirth or a malformation. What is meant with umbilical cord bloomen? I have never heard that expression. Is it a malformation? – The material is really too small to study rare conditions like these and if one want to compare unusual outcomes between the two groups, these must be defined a priori. I think one could just write in the text that one and four infants in the two groups were stillborn and that one and two cases, respectively, were malformed.
7.	I have a number of minor comments:
Line 39 (Abstract): --- adjusting for maternal age and parity. In one edition of the Abstract it says promiparity (I suppose you mean primiparity), in the other Abstract parity. Which is it?
Line 79: why write monochorionic and dizygotic, why not use monozygotic and dizygotic or monochorionic and dichorionic?
Line 125: When cesarean delivery exceeds 1000ml. Re-formulate!
Line 129: - the water amount of sheep—What is meant? I suppose this is a definition of polyhydramniosis but I don’t understand what sheep do here.
Line 141: one ‘the’ is enough. ‘Number of twins’ is not quite clear – it could also be the number of twin deliveries. In this connection, point out the complication with a tie between data for the two infants in a twin pair.
Line 148: A ----model  was established------, adjusting for potential---.  I don’t think that data can be significant, differences can.
Line 165: But you have shown that the higher rate of GDM was due to age and parity! If you want to present the crude percentages you should add the explanation, now mentioned first on line 173.
Line 260: The infertility factors do not lead to insufficient power – low number of cases does!
Table 3: I think 15 growth discordances in 249 twin pairs are 6.0%. Actually, I don’t suppose that the papyraceus fetus can (and has) been included so it should be 15/248, still 6.0%.


Instruction: You are one of the reviewers, your task is to write a review for the article. You will be given the title of the article, the number of the round in which the article is located, and your order among the reviewers.

Input:
Title: OBSTETRIC AND PERINATAL OUTCOMES OF DIZYGOTIC TWIN PREGNANCIES RESULTING FROM IN VITRO FERTILIZATION VERSUS SPONTANEOUS CONCEPTION: A RETROSPECTIVE STUDY
Review round: 3
Reviewer: 1

Output:
Basic reporting: 1. Basic Reporting

The submission adheres to PeerJ policies. Raw data are supplied.

The manuscript includes sufficient introduction and background which demonstrate how this study fits into the broader field of knowledge. The relevant prior literature is appropriately referenced.

All necessary corrections were performed.

However, authors have rewritten the abstract according to one of the reviewers advise. On the other hand, by doing so they have made it less informative. I advise that instead of current abstract authors write:

The study aimed to investigate if twin pregnancy conception modes (spontaneously or by In Vitro Fertilization - IVF) are associated with adverse obstetric and perinatal outcomes. Sample included 470 dichorionic twin pregnancies out of which 249 resulted from IVF and 221 were conceived spontaneously. Women in the IVF-conceived group apart from being older and more often nulliparous had all other investigated parameters similar to the counterparts in the spontaneous conception group. A higher risk of stillbirth and malformation (4.8% versus 1.4%, P< 0.05) and increased neonatal intensive care unit (NICU) admissions (23.4% versus 12.3%, P < 0.05, respectively) were observed in the IVF-conceived group. After adjusting maternal age and primiparity, the results showed that there were no significant differences between the two groups (P > 0.05) in terms of maternal antenatal complications and neonatal outcomes. In conclusion, IVF treatment does not increase risks for pregnancy-related complications and adverse neonatal outcomes in dizygotic twin pregnancies.
Experimental design: This is original research. Research question is well defined, relevant and meaningful. The investigation seems to be performed according to high technical and ethical standards.

All necessary corrections were performed.
Validity of the findings: Data is statistically sound and controlled.

The discussion part is adequately written.

Conclusions are linked to the original research question and based on the obtained results.

All necessary corrections were performed.
Additional comments: This study deals with an interesting and important issue of perinatal and neonatal outcomes of dichorionic twin pregnancies regarding their conception method. Growing interest has been paid to the role of IVF-ET in obstetric and neonatal outcomes of twin pregnancies. Still, as the results of available literature remain to be inconsistent this study is current and relevant.

All necessary corrections were performed.