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: METHODS OF BODY TEMPERATURE ASSESSMENT IN CONOLOPHUS SUBCRISTATUS, CONOLOPHUS PALLIDUS (GALÁPAGOS LAND IGUANAS), AND AMBLYRHYNCHUS CRISTATUS X C. SUBCRISTATUS HYBRID
Review round: 1
Reviewer: 1

Output:
Basic reporting: The writing is clear, as are figures.  Methods are adequately described, and the data are provided.
Experimental design: The sampling design also appears fine.  I have some concerns with the analyses used (see below).
Validity of the findings: The findings seem valid (with the caveat of the statistical issues) and uncontroversial.  Some more thought needs to go into the context in which the findings might apply beyond this system, however.
Additional comments: Nice neat manuscript.

63: it might be worth mentioning that the degree of variance from the environment temperature is affected by the size of the animal (its thermal inertia) as well as how quickly the environmental temperature shifts.  Interesting points here, because you have a large reptile (high inertia, so potentially will deviate to a large extent), but it is in a fairly stable thermal environment (i.e., equatorial island).

85: since these devices average temperature over an area, it might be worth working out what size surface area is measured when you hold your particular IR gun at 5-7cm from the animal.

92: "departure from sphericity". What is that, exactly?  If you are talking about a univariate response variable (i.e. temperature), then departure from normality would be the more usual criterion.

95: Unusual also to report a standard linear model (i.e. normal error distribution) as a glm.  Not incorrect, just unusual.  If you are reporting it as a glm, then pls specify error distribution (presumably, normal) and link function (presumably identity).  Alternative analysis pathway (below) would obviate this point.

Using multiple regression with highly correlated predictor variables is problematic, and can lead to massively inflated standard errors on coefficients (and so parameter estimates that jump all over the place).  I think rather than a multiple regression (or glm) you should probably just use simple pairwise correlation coefficients (r, plus plots) to show that all four measures are highly correlated.  You could then do both of a) choose the external temperature with the highest r-value as your best single predictor of internal temperature, and b) extract the first principal component of external temperature measures as a compound variable.  You then run a simple linear model to predict internal temperature from a) the best single predictor, and b) the compound external temperature measure.

I don't think you need p-values anywhere in this manuscript.  Except, maybe, to show the correlations are all significantly different from 0.  Much more important are the parameter estimates (r, and partial coefficients) and their SEs.

In the Discussion, I think you need to put some thought into how reliable the internal/external comparison would be if animals were subject to a rapid temperature change (e.g., in/out burrows; in/out of shade).  This goes to the generality of your findings -- under what conditions would you expect internal and external temperatures to align?


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: METHODS OF BODY TEMPERATURE ASSESSMENT IN CONOLOPHUS SUBCRISTATUS, CONOLOPHUS PALLIDUS (GALÁPAGOS LAND IGUANAS), AND AMBLYRHYNCHUS CRISTATUS X C. SUBCRISTATUS HYBRID
Review round: 1
Reviewer: 2

Output:
Basic reporting: This paper is very poorly written, and does not meet the most basic standards required for a scientific paper.

There is no significant background or context to place the study within the scientific literature.  The authors should examine papers comparing other thermal methods in a similar manner to see how to better situate their study and its results.

The figures do not provide enough information to allow us to evaluate the science, they are presented in a naive way.

The paper does not address any thermal literature at all (even the methodological literature) which is substantial.  The authors should read this literature to see how to present their data.
Experimental design: 1. This study could probably provide interesting information to the scientific community.
2. Moderately well defined, but not really situated, stated how it fills a gap for 2 species of lizard, but could be broader.
3. Data collection seems to be fine, but presentation is inadequate.
4. Methods okay
Validity of the findings: 1. This is apparently not replication of exisiting results.

2. Data is probably robust and sound.

3. Conclusions are not situated in exisiting research, and difficult to evaluate because research presentation is so poor.

4. Speculation is not relevant here.
Additional comments: Review of Methods of body temperature assessment in Conolophus subcristatus and Conolophus pallidus (Galápagos land iguanas).
Title - Broaden to include largish land reptiles more generally?

Abstract - does the MS have any broader significance? I would not start with the study animal, but instead with the second sentence, eventually introducing the land iguanas as a study system.
Line 30 - I do not see 'captivity' and 'research' as mutually exclusive.
Lines 30-32 - I think the majority of research on ectotherms emphasizes that their body temperatures can be quite different from ambient because they behaviourlly thermoregulate - this sentence seems misleading
Lines 32-35 - emphasise that they are large - we have done this on (much) smaller reptiles and it did not work as a method, because too much of the background was measured by the 'gun'

Introduction

Again, do not start with the study animal
Line 60 - do not contrast research & captivity - what do you really mean?  For care and data collection on wild animals?  Something like that?

Methods

Study dates?
Line 91 - are repeated measures the best way to determine this?  It seems to me that you have compared 4 different methods of taking the temperature on one iguana - maybe better to control for variation due to individual using a random factor in the model?  That would save you from Mauchley's test which is overly conservative when sample sizes are small…

Line 93 - between 2 things, among many

Line 93-94 if you have a significant ANOVA there is no need to Bonferroni correct post-hoc tests

Results

In general, in the figure and table captions, it is not necessary to put 'bar graph of' or 'line graph of' - it is obvious what kind of graph it is.  Start with the data "Means ± SDs of xxxxx"

Table 1: It would be good to report more than just the standard deviations here - ranges are probably the most useful - more importantly, I think Fig 3 reports the same data.  It would be better to show a box-and-whisker plot of each of these so we can get a feel for the data distribution of each measurement in relation to the others, and get rid of table 1 all together

Figure 2 - what is the x-axis of figure 2?  Iguana number?  It is difficult to see what information we can derive from this graph.  It is hard to see the overlapping lines.  If you plotted the box and whisker plot recommended for figure 1, that would help us see the bias of different methods, if there were any.  Another graph might be to show all 4 dots for each iguana (no line - there is no reason to connect these), which might show variation among methods within animals, which might be interesting.

Discussion

Line 123-126 - the slight underestimation of the 3 external Tbs, and their relative positions should be obvious from the figures, but I don't see it, the figures have to be targeted to help the audience see this

Lines 127 - 131 - why was femoral temperature better than dorsal temperature as a predictor?  Was it less variable?  More explanation is needed here

There needs to be more discussion of outcomes of the different methods - did one method work well on cold days?  What about hot days?  Why were some individuals super cold and others very hot in your data?

What is iguana preferred temperature?  Were they able to reach it?  How is this relevant to their health status if this is not reported?  How different were they from ambient?


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: EFFECTS OF PARTICLE SIZE ON PHYSICOCHEMICAL AND FUNCTIONAL PROPERTIES OF SUPERFINE BLACK KIDNEY BEAN (PHASEOLUS VULGARIS L.) POWDER
Review round: 1
Reviewer: 1

Output:
Basic reporting: These aspects of the manuscript are fine.
Experimental design: All of these are fine, but regarding the second point (research question well defined, relevant & meaningful, stated how research fills an identified knowledge gap), see the general comments.
Validity of the findings: see general comments
Additional comments: The manuscript is well written and easy to understand, and the data are presented in a clear manner using typical formats. However it is not clear what new information is presented in the study, in light of the background literature discussed in lines 48-71 of the introduction. It is well known that grinding any food material to a very fine powder will make it easier to extract components from it. Also, it is obvious that finely ground foodstuffs will absorb water faster and better than coarser materials. So it needs to be explained how super-finely ground black kidney bean flours are somehow unexpectedly different than anything else so treated. The physical data including the SEM images serve only to confirm that the material has been reduced in size by the grinding, with the inevitable changes in surface area, flow properties, etc. The data that show higher amount of antioxidants in superfine flour are misleading, since it is obvious that more antioxidants are extractable and thus detectable in the finer flour. Antioxidants are not synthesized or produced by grinding, nor can they be increased by mechanical degradation of other components by grinding. It cannot be concluded that superfine flour has more of something the detection of which is a function of the particle size.

The use of superfine black kidney bean flour to absorb cholesterol from animal fats is hard to imagine as a practical approach. If such a use is proposed, at least it would be necessary to compare the performance of the flour with other adsorbents such as activated charcoal or clay, for example. Foods prepared with superfine black kidney bean flours would not absorb cholesterol from other foods consumed in the diet, as the flour components would be incorporated into the food and thus not be in a superfine state after ingestion.

Some aspect of the superfine black kidney bean flour that is different from other superfine kidney bean flours, other superfine pulse flours, other superfine grain flours, or other superfine foods in general needs to be shown, other than properties of the black kidney beans themselves, which are known.


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: EFFECTS OF PARTICLE SIZE ON PHYSICOCHEMICAL AND FUNCTIONAL PROPERTIES OF SUPERFINE BLACK KIDNEY BEAN (PHASEOLUS VULGARIS L.) POWDER
Review round: 1
Reviewer: 2

Output:
Basic reporting: The manuscript is fairly well-written, well-organised and easy to read.
Experimental design: In the manuscript, the procedures for the experimental techniques were adequately described although in some aspects, improvements can be made by providing the necessary details.

1. It is common to have a botanist to authenticate the samples that are used in any study.
2. Please state the time used to mill the beans in the domestic disc-mill. Would be beans be overheated during the 10 min milling time?
3. How did the authors choose a concentration of 5 mg/ml for two of the antioxidant assays? The concentration of samples used for the hydroxyl radical scavenging assay was not stated. The metal chelating assay is not referenced.
4. Did the authors suspend the milled bean samples into water and directly use them for the antioxidant assays? Why this method is chosen instead of preparing extracts from the milled samples?
Validity of the findings: Overall, the authors presented their results in a systematic manner and interpreted their data carefully.
Additional comments: The manuscript described the effects of particle size of black kidney beans on their physicochemical and functional properties. The authors characterised the milled samples in terms of particle size distribution, surface area size, colour, flow property, water holding and water retention capacity, as well as thermal property.This part is fairly straight forward. In addition, the bean samples were also demonstrated to have cholesterol absorption and antioxidant properties. Overall, I think the manuscript contains findings that might be useful for the nutraceutical industry. Nonetheless, several issues need to be addresed:

The authors need to justify why dose-response studies have not been carried out (in place of a single dose analysis, and how the dose was chosen). It is a standard practice to express the results in terms of IC50 values so that comparisons can be made with appropriate positive controls (missing data) and data in the literature. The authors stated that their findings on the correlation of particle size of samples and increase in antioxidant activity were in agreement with previous studies but there is little attempt to discuss the possible reasons, which in turn needs to be supported by evidence from the literature. The manuscript will also benefit from a more thorough discussion, perhaps the authors can compare and contrast their results with previous related work. A mention of some potential further work is suggested.


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: EFFECTS OF PARTICLE SIZE ON PHYSICOCHEMICAL AND FUNCTIONAL PROPERTIES OF SUPERFINE BLACK KIDNEY BEAN (PHASEOLUS VULGARIS L.) POWDER
Review round: 2
Reviewer: 1

Output:
Basic reporting: no comment
Experimental design: no comment
Validity of the findings: The rationale and benefit to the literature is not clearly stated, as most if not all of the results have previously been cited or are obvious consequences of the treatment.
Additional comments: The responses and revisions based my comments, though lengthy, are tangential and circumlocutory, and do not really address the points made. In response to the comment about data showing that the particles become smaller and have different shapes after superfine grinding, more data and references that confirm that obvious fact are now presented. In response to the comment that finer samples are more extractable and hydratable and therefore could be expected to give different analysis results, again it is repeated with more literature precedents and explanations, some contradictory. In response to the comment that using superfine red kidney bean flour as a cholesterol absorbent is an arbitrary and expensive option, some additional references were added and an example of using it as filler in simvastatin tablets was proposed. Recycled newsprint contains the same components stated to be relevant to this functionality in SRKBF. It is still not clear what is unexpected about any of the experimental findings, even though the manuscript is now somewhat longer. If possible, the authors should consider addressing some of these issues in the discussion.


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: EFFECTS OF PARTICLE SIZE ON PHYSICOCHEMICAL AND FUNCTIONAL PROPERTIES OF SUPERFINE BLACK KIDNEY BEAN (PHASEOLUS VULGARIS L.) POWDER
Review round: 3
Reviewer: 1

Output:
Basic reporting: no comment
Experimental design: no comment
Validity of the findings: The editor will have to decide whether this manuscript is a repetition of well-known, widely accepted results.
Additional comments: Please add an explanation of why it is unexpected that finer particle size will increase water uptake efficiency, make plant constituents more extractable, or absorb more cholesterol, and why black kidney beans would exhibit different responses to this treatment than any other pulse or grain product.


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: EFFECTS OF PARTICLE SIZE ON PHYSICOCHEMICAL AND FUNCTIONAL PROPERTIES OF SUPERFINE BLACK KIDNEY BEAN (PHASEOLUS VULGARIS L.) POWDER
Review round: 3
Reviewer: 2

Output:
Basic reporting: No comment
Experimental design: No comment
Validity of the findings: No comment
Additional comments: The manuscript has been revised based on the comments of the reviewer. I agree to some of the previous reviewer's comment and the authors have attempted to address them. Nonetheless, I do think the findings presented here have merits to be considered for publication. Language correction is recommended to improve clarity in some parts of the manuscript.


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: RECENT DATING OF EXTINCT ATLANTIC GRAY WHALE FOSSILS, (ESCHRICHTIUS ROBUSTUS), GEORGIA BIGHT AND FLORIDA, WESTERN ATLANTIC OCEAN
Review round: 1
Reviewer: 1

Output:
Basic reporting: The MS is written in clear and unambiguous English. A few typos are noted throughout the attached annotated PDF, but otherwise the prose is quite good. The literature references are  up to date and thorough. One suggested addition is Peredo and Uhen 2016 (Palaeogeography, Palaeoclimatology, Palaeoecology), which discusses marine mammal biogeography via the arctic passageways. The article, figures, and tables, are all structured according to house style. The MS is written to be concise and to restrict itself to the relevant hypotheses and data with no off topic speculation.
Experimental design: The MS falls entirely within the aims and scope of the journal and is original, primary research of good quality. The questions are well defined, the data address their questions, and their conclusions are reasonable given the results. All experiments are performed to high standards, and the methods are sufficiently described to facilitate replication.
Validity of the findings: The data support the overall findings in such a way that I see little reason to disagree with the interpretation presented by the authors. I do not doubt the ages of the fossils present, nor the identity of the fossils presented. The authors are modest in their phrasing, suggesting that these fossils may suggest a calving ground: an assertion that I think is reasonable given the data presented.
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: RECENT DATING OF EXTINCT ATLANTIC GRAY WHALE FOSSILS, (ESCHRICHTIUS ROBUSTUS), GEORGIA BIGHT AND FLORIDA, WESTERN ATLANTIC OCEAN
Review round: 1
Reviewer: 2

Output:
Basic reporting: The manuscript describes a number of fossil finds assigned to the gray whale Eschrichtius robustus from the western North Atlantic ocean and investigates into their ages through Accelerator Mass Spectrometry (AMS). As a whole, the manuscript is well written with good technical English and does not require further revision. The research included in this manuscript is interesting for a technical, international audience. As the results are interesting and well grounded, the manuscript is worth publishing but only after minor revision.

English: good.
Literature: good.
Article structure: minor revision
Results: good.
Experimental design: The experimental design seems appropriately realized. Techniques and methods are adequately explained and only minor changes are necessary in order to increase the readability of the manuscript for a broader audience.

Original primary research within aims and scope of the journal.
Research question well defined, relevant and meaningful. It is stated how research fills an identified knowledge gap.
Rigorous investigation performed to a high technical and ethical standard.
Methods description needs only a minor revision to be sufficiently well described.
Validity of the findings: The findings are globally and methodologically valid. The chronological placements of these fossil whales provide new and interesting data to understand the evolution of the gray whale populations in the North Atlantic in the Pleistocene and Holocene. Moreover, the hypothesis that sites along the coasts of Florida formed reproductive areas for gray whales in the Pleistocene and Holocene is interesting and useful to understand patterns and processes of extinction in this species.

The manuscript presents novel interpretations and new results for the field. Data is robust, statistically sound and controlled. Conclusion need a minor revision. The speculative part of the manuscript (dealing with proposed reproductive sites for Pleistocene and Holocene gray whales) is well identified as such.
Additional comments: My comments are listed below.
Line 82: AMS: please, provide citations to support that this method is appropriate for the goals of the paper.
Lines 148 and 168: provide geographic coordinates in a consistent manner: you used 27°07’40” North latitude and 80°08’45” West longitude and 30°17’N, 81°23’W; the latter way is the best.

Line 157: Justify the statement that the specimen “is from a very young individual or calf probably less than a year old”.

Lines 140 and 162: use coquina or “coquina” consistently throughout the manuscript.

Line 183: you have parentheses to open somewhere.

Lines 238-241: please explain what are the eschrichtiid attributes of these vertebrae; moreover, explain why the vertebrae are assigned to the thoracic section of the vertebral column because, judging from the image you provided, at least one seems part of the lumbar section because the transverse processes start from approximately the middle of the height of the vertebral body. Additionally, a synthetic description of the periotic is needed.

Lines 249-255: details of the temporal fossa are necessary. What are the relationships of the alisphenoid with the other bones; what is the shape of the squamosal cleft? Additional figures and descriptions are necessary if the authors want to publish a paleontological section of this paper. Otherwise, remove all the paleontological part.

Lines 258-259: I was unable to find any information in Table 1 to confirm the juvenile age of the specimen. Why the authors cited Table 1 in these lines? Please, explain or remove the Table 1 citation.

Line 275: The authors identified the previous paragraph under the title Paleontology. Here a new section is starting that needs a paragraph title. After the title, remove Furthermore, and rephrase accordingly to the new paragraph structure.

Line 373: change e.g. into hereinafter:

Line 378: use the symbol – consistently in this phrase.

Line 392: Correct the blank space.

Lines 384-399: report your finds with more details. You should report the dates of the fossils here before making a synthetic discussion.

Judging from Fig. 5, there is also a gap in the interval between 100 and 1000 14C calibrate date. Can you discuss this gap? Moreover, change 14C into 14C in the label for the calibrate date in the figure.

References
Check the reference list strictly. Below, I list some problems I found but my list is not complete. Be consistent and strictly follow the instructions to realize your reference list. For example: you wrote 51(2):647-655 for Cherkinsky (2009) and 26, 405–413 for de Bruyn et al. (2011). Moreover, citations are sometimes incomplete (Collins et al. 2010 lacks pages; Alter et al. is cited as volume 24.7); check also George et al. (2004) for comma placement, McLeod et al. (2008) lacks the number of the volume etc. etc.

Line 419: include all the authors in the Alter et al. paper.
Lines 440-441: add a blank line separating the citations.
Lines 447-448: remove “ and ” from the citation.

Illustrations
Fig. 2: add inventory number of Rotterdam specimen; B represents a medial view of both specimens not a lateral view. Change the caption. Why parts A and B of Fig. 2 are not together with parts C and D? It seems that they belong to different figures. Authors must provide also lateral and ventral views of these vertebrae to confirm assignments to the thoracic region of the vertebral column; in fact, judging from the provided photographs, at least two vertebrae seem to belong to the lumbar section as the bases of their transverse processes are located approximately at the middle of the height of the vertebral body.
Fig. 3: illustrations are very small and difficult to read. There is a lot of space that can be filled with larger illustrations. I recommend authors to enlarge the single illustrations (views of the skulls and periotics) in order the audience can better understand the morphologies of the specimens.
Table 1: what do exactly the author mean for “paraoccipital”? Additional measurements are needed in order to can include these specimens in broader morphometric datasets. I list these below:
a)	Maximum height and maximum width of foramen magnum;
b)	Maximum length of supraoccipital from higher border of the foramen magnum to its apex;
c)	Maximum width of foramen magnum + width of both occipital condyles (this may be used for size reconstruction of the whale);
d)	Bizygomatic width.
There are no measurements of the periotic. The following measurements are needed:
a)	Length of posterior process;
b)	Maximum width of posterior process;
c)	Lateromedial diameter of pars cochlearis;
d)	Anteroposterior diameter of pars cochlearis;
e)	Maximum height of the periotic;
f)	Maximum and minimum diameters of internal acoustic meatus;
g)	Maximum and minimum diameters of fenestra ovalis;
h)	Maximum and minimum diameters of fenestra rotunda.


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: RECENT DATING OF EXTINCT ATLANTIC GRAY WHALE FOSSILS, (ESCHRICHTIUS ROBUSTUS), GEORGIA BIGHT AND FLORIDA, WESTERN ATLANTIC OCEAN
Review round: 1
Reviewer: 3

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


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: RECENT DATING OF EXTINCT ATLANTIC GRAY WHALE FOSSILS, (ESCHRICHTIUS ROBUSTUS), GEORGIA BIGHT AND FLORIDA, WESTERN ATLANTIC OCEAN
Review round: 2
Reviewer: 1

Output:
Basic reporting: This study is written in clear and professional English. The references are sufficient and and the manuscript presents all arguments, evidence, and rationale in clear and consistent formats.
Experimental design: No comment.
Validity of the findings: No comment.
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: RECENT DATING OF EXTINCT ATLANTIC GRAY WHALE FOSSILS, (ESCHRICHTIUS ROBUSTUS), GEORGIA BIGHT AND FLORIDA, WESTERN ATLANTIC OCEAN
Review round: 2
Reviewer: 2

Output:
Basic reporting: The manuscript appears slightly modified from the previous version. Illustrations are better prepared and can be easily observed. Some elements of the text were modified accordingly to the reviewers' recommendations but, as stated by the authors in their rebuttal letter, they maintain some views about their methods that the reviewers criticized. In particular, the paleontological analysis is superficial and certainly insufficient to support the taxonomic decisions made by the authors about the vertebrae. The paleontological section is quite superficial with insufficient descriptions and measurements of skulls, mandible and vertebrae. The vertebrae should be removed from the manuscript otherwise their assignment to Eschrichtiidae has to be better established. If the authors want to maintain the vertebrae in the manuscript then  the manuscript needs major revisions before being accepted for publication; if the authors agree to remove the vertebrae then the manuscript needs minor revisions. Certainly, as detailed in the other sections of this review, in its present version, this manuscript should not be accepted for publication as a number of revisions is still to be made by the authors.
Experimental design: Original primary research within Aims and Scope of the journal.

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

The paleontological investigation is insufficient. The methods followed in the paleontological analysis are not sufficiently explained and the authors failed to provide enought details to replicate their observations and to support their taxonomic conclusions about the vertebrae. The methods followed for skull descriptions are not sufficiently explained and the resulting descriptions are too superficial.
Validity of the findings: While the skulls can be assigned to Eschrichtius based on the illustrations, questions still exist about the vertebrae and the dentary. Moreover, the insufficient descriptions of the skulls and periotic do not allow the clear identification of the specimens as Eschrichtius robustus so that a hypothesis of a different species assignment still holds. More detailed descriptions are necessary to better support taxonomic decisions. In the end, the conclusions are not sound for a number of specimen examined in this manuscript.
Additional comments: The paleontological section is quite superficial with insufficient descriptions and measurements of skulls, mandible and vertebrae. In the rebuttal letter, the authors wrote that their assignment of the fossils to Eschrichtius is based firstly on identificiations made by other authors but they failed to document on which bases these authors made their choice. This is somewhat an Aristotelian way to go: as these authors said that the bones belong to Eschrichtius then these bones belong to Eschrichtius. This reasoning is not acceptable in a scientific manuscript. The readers have the right to know and the authors of the current manuscript have the duty to explain what characters were used to assign the vertebrae to Eschrichtius in order enable other students to do the same observations and eventually falsify their hypothesis. Presently, their assignment of the vertebrae to Eschrichtius is based on a comparison between morphometric characters that is not fully explained (see below). Frankly speaking, I would remove the vertebrae from the manuscript or state that they are belonging to Mysticeti gen. et sp. Indet. Even in this case, the skulls and the dentary are enough to support the paleoecological hypothesis of the authors about the breeding ground.
I must stress what written by the authors in the rebuttal letters as they stated that the requested additional descriptions and measurements are not necessary because out of the scope of the paper. In fact, the authors stated that in their opinion these requests would be useful for taxonomic purposes only but their goals are different. They were wrong: additional descriptions and measurements are needed to better describe the specimens and to support the taxonomic conclusions. From the present manuscript, taxonomic conclusions are really scarcely supported, therefore a full description of the specimens would provide a better support: they need to have more characters to support their taxonomic decisions. I strongly recommend to add morphological details to the paleontological section of this manuscript to better support both the taxonomic decision and the paleoecological hypothesis.
Line 47: A monotypic taxon is a group (taxon) including only one immediately subordinate taxon. Based on this manuscript, this means that Eschrichtiidae should include only Eschrichtius. This is not the case: there are four putative genera of Eschrichtiidae: Eschrichtius, Archaeschrichtius, Eschrichtioides and Gricetoides. Thus, the family is not monotypic. The authors have to state, eventually, that the family Eschrichtiidae includes only one living genus and species, Eschrichtius robustus.
Line 47: it is interesting to note that the authors include only one morphology-based citation about the phylogenetic and taxonomic relationships of Eschrichtiidae (i.e., McLeod et al. 1993). It would be useful to cite also more recent works of this kind such as Deméré et al. (2005; Journal of Mammalian Evolution), Steeman 2007; Zoological Journal of the Linnean Society), Bisconti (2008; Zoological Journal of the Linnean Society), Whitmore & Kaltenbach (2008; Virginia Museum of Natural History Special Publication).
Impossible to open fig. 4
Line 258: in my knowledge, the remnants of the lateral processes are not diagnostic at family level for Eschrichtiidae. If the authors think that this character is diagnostic than they have to demonstrate that. If they are unable to perform such a demonstration, they have to remove this character from the list.
Line 258: overall centrum size: this parameter is linked to the ontogenetic age of the individuals. Are the authors argumenting that the overall centrum size of these juvenile vertebrae are consistent with values for this parameter as scored from living gray whale individuals of the same ontogenetic ages? Did they compare their measurements with a sample of gray whale individuals of different ages? In general, the overall centrum size is not a good proxy for a morphological identification of a whale species unless the size is really peculiar (e.g., in the adult blue whale).
Line 259: at least balaenopterid in origin: this means that there is no certainty about the assignment of these vertebrae to Eschrichtiidae as there is a possibility that they belong to a balaenopterid whale. The paleoecological conclusions of the authors depend upon the clear and correct identification of these fossils as belonging to gray whales; if this identification is not possible beyond each reasonable doubt then the conclusions are weakened. This phrase undermines a strong uncertainty in this research and makes really weak conclusions.
Line 259: it is not correct to talk about “key data” as the datum is only one: the ratio of centrum length to centrum height. The authors have to state that their assignment of this vertebra to Eschrichtiidae depends upon this measurement only.
Line 266: In general, there are quite clear criteria to distinguish cervical, thoracic, lumbar and caudal vertebrae in a mysticete skeleton. Thoracic vertebrae have the transverse processes located in the anterior-most part of the lateral wall of the centrum and bears articular facets for the heads of the ribs. This characters should be sufficient to assign the vertebrae to the thoracic section of the vertebral column. Do the authors can check this character and report in the manuscript about it? Noting the position of the remnants of the lateral (better: transverse) processes would be feasible in the materials they are studying.
Line 291: squamosal cleft is present also in Balaenopteridae and some Cetotheriidae. What is the shape of the squamosal cleft? In Balaenopteridae the squamosal cleft has a triangular shape with a dorsally directed apex; in Cetotheriidae and Eschrichtiidae the shape is straight. Noting the presence of a squamosal cleft is insufficient to make an assignment to Eschrichtiidae, description is necessary.
Impossible to open fig. 6
If the taxonomy was correct, then the paleoecological conclusions would be sound but, unfortunately, the taxonomic decisions made by the authors are biased by a number of issues. I addressed these issues in the line-per-line comments. In the present version of the manuscript, the paleontological section is still superficial and unable to support the taxonomic decisions about the vertebrae. Additional descriptions of the skulls are necessary to allow the readers to fully understand morphology and taxonomy of the specimens.


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: RECENT DATING OF EXTINCT ATLANTIC GRAY WHALE FOSSILS, (ESCHRICHTIUS ROBUSTUS), GEORGIA BIGHT AND FLORIDA, WESTERN ATLANTIC OCEAN
Review round: 2
Reviewer: 3

Output:
Basic reporting: See general comments.
Experimental design: See general comments.
Validity of the findings: See general comments.
Additional comments: This is my second review of this paper. The authors have made a bona fide attempt to reply to the reviewers' comments, and I think the paper has notably improved as a result.

There is still an issue with a couple of the figure captions:

1) The caption of Fig. 2 still states in l. 119-120 that GMNH 4281 and NMR9991-00001783 are "right" mandibles and shown in "lateral" view. This is incorrect: both specimens are *left* mandibles and shown in *medial* view (this is obvious from the fact that the mandibular foramen, the symphysis, and the gingival foramina are all clearly visible).

2) The caption of Fig. 3 (l. 129) should specify that the periotic is shown in medial (left photo) and lateral (right photo) view. I still think that it would be better to assign individual labels (G and H) to these photos.

Otherwise, I have no further comments to make. Occasionally, modifications appear to have been carried out somewhat hastily, which means that the manuscript might benefit from another round of proofreading. For example, l. 94 states: "[...] f one dentary, three puted dentary elements [...].

In general, however, this paper is ready to be published.


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 RISE OF FEATHERED DINOSAURS: KULINDADROMEUS ZABAIKALICUS, THE OLDEST DINOSAUR WITH ‘FEATHER-LIKE’ STRUCTURES
Review round: 1
Reviewer: 1

Output:
Basic reporting: This is a good manuscript with only a few issues that I can see.    The writing is very clear and mostly free of errors or gramatical issues.  The literature review is good and I cannot find any issues on this front.

The figures are not as good as one would hope.  Figure 1B is very small and hard to see.  It only shows what appears to be talus, not any stratigraphy.  I would suggest combining figure 1A and Figure 2.   I would remove Figure 1b and include it with Figure 3 instead.  I would also like some high quality photos of each of the trenche sections. The stratigraphic column in Figure 3 is ok, but insufficient.   I say this because there are inconsistencies in the manuscript over what was actually dated, which the methods stating volcaniclastics vs volcanic ash in quite ambiguous ways.  I want to see photos of the ash beds and volcaniclastic deposits. This needs to be much more clearly stated.  See comments in manuscrip and figure captions.

My number one concern is the apparently relaxed nature of the dating process.  The authors state that monazite and zircon with dated, apparently together? and used to produce the reported ages.   There is no mention of SEM or CL imaging used in the laser spot selection.  This part of the paper needs to be cleaned up and clarified.  If you are procuding ages from mixed populations of zircon and monazite, I want to know why and what different standards were used. Why are zircon ages and monazite ages not shown separately?  This just needs a bit of cleaning up. I would like to understand what kind of screeing was used to select grains for dating, etc...

I found the conclusions well reasoned and solid.

In sum, good paper.  Just needs a bit of tightening up.
Experimental design: Very good aims and scope.

The research questions and motivations are clear and valuable.

See points above regarding the methods.  These are not as sound as they could be. Work is needed.
Validity of the findings: The only thing that I am not comfortable with is the dating approach combining monazite and zircon ages to apparently arrive at the reported concordia ages.   This needs to be explained.

Otherwise the dating results look fine.
Additional comments: See comments above and in the attached manuscript.


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 RISE OF FEATHERED DINOSAURS: KULINDADROMEUS ZABAIKALICUS, THE OLDEST DINOSAUR WITH ‘FEATHER-LIKE’ STRUCTURES
Review round: 1
Reviewer: 2

Output:
Basic reporting: I have read and assessed the manuscript "The rise of feathered dinosaurs: Kulindadromeus
zabaikalicus, the oldest dinosaur with ‘feather-like’ structures." I have read the entire manuscript but will mainly restrict the feed-back on the palynology, which is my area of  expertise.

This is an extremely well written manuscript, both concerning language and the organization of the paper. The manuscript is easy to follow, all through even for a non-vertebrate specialist.  The palynological part is thorough, and the figures nice and necessary. It is difficult to date Jurassic terrestrial deposits by palynology but the authors have carefully built up their case.

The only minor issues that I can find is that Quadraeculina is misspelt  (line 218) 8th letter should be a c instead of a q. I also miss a palynological photographical plate showing the main taxa – it is not crucial to include as the stratigraphical fig no. 6 is sufficient, but it would be nice to have one in the supplementary part, if possible.

Also some more recent relevant references are lacking:

Shevchuk, O., Slater, S. M., & Vajda, V. 2018. Palynology of Jurassic (Bathonian) sediments from Donbas, northeast Ukraine. Palaeobiodiversity and Palaeoenvironments, 98(1). https://doi.org/10.1007/s12549-017-0310-3
Slater, S. M., Wellman, C. H., Romano, M. & Vajda, V. 2018. Dinosaur-plant interactions within a Middle Jurassic ecosystem palynology of the Burniston Bay dinosaur footprint locality, Yorkshire, UK. Palaeobiodiversity and Palaeoenvironments, 98(1). https://doi.org/10.1007/s12549-017-0309-9
In summary, I suggest a very minor revision based on the palynological contribution. The rest of the manuscript is well-written and most probably correct but as I can´t judge this with certainty I leave those parts to other referees. I hope to see this manuscript in print as it contributes some interesting results.
Sincerely
Experimental design: Fine
Validity of the findings: Interesting with broad relevance.
Additional comments: See above.


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: AFRICAN SAVANNA ELEPHANTS (LOXODONTA AFRICANA) AS AN EXAMPLE OF A HERBIVORE MAKING MOVEMENT CHOICES BASED ON NUTRITIONAL NEEDS
Review round: 1
Reviewer: 1

Output:
Basic reporting: -The text is written in professional English. Splitting long sentences in further short ones would make it much easier to read and follow the content. Very often “;” is used to link sentences which reduces the text flow. I recommend omitting this wherever possible.

-The introduction shows the background and context of the work sufficiently and clearly. Throughout the text I repeatedly missed citations close to the statements made out of them. The reference list needs thorough revision as indicated in the pdf.

-In my opinion the subject is definitely of broad interest especially regarding the currently existing (and in the future probably aggravating) human-elephant conflict.

-Functioning as basis for a potential approach to mitigate human-elephant (or more broadly human-wildlife) conflict, seems to me a very good reason for this review article.

-The introduction provides sufficient background information and makes clear who the intended audience is.
Experimental design: -The methods are described in a concise manner, providing sufficient detail to replicate the study.

-The chosen method seems appropriate to me to comprehensively coverage the subject. If both the African and the Asian elephant species had been included throughout the study, this might have led to even more complete findings.

-In my opinion, sources are quite often not cited as clear as I prefer it to be (see comments made in the pdf). This might be overcome by citing statements closely and not only at the end of the corresponding section.
Validity of the findings: -Conclusions are stated and linked to the original research questions. Unresolved research questions are identified as well as future fields for research.
Additional comments: -With respect to the situation of free-ranging elephant populations and the increasing conflict with humans, the intention of this article seems very important to me. It combines different fields (elephant nutrition, mineral content in feeding plants, herbivore movement patterns, conservation) of research, which is a quite challenging task.

-In my opinion the structure of the manuscript needs to be revised to make it clearer. I would recommend doing this by the use of the following subheadings:
Author cover page (no adaptation required)
Abstract (no adaptation required)
Introduction (no adaptation required)
Survey methodology (should include text from line 105 to 134)
African elephant feeding behavior
Elephant nutrition requirements and the domestic horse model
Reported mineral requirements and deficiencies in elephants (might be included in the previous subheading)
Effect of geochemistry on elephant dietary intake
Geochemistry influencing animal movement and land use decisions of herbivores
Land use decisions of elephants
Conclusions (no adaptation required)
References

-Considering the human-elephant conflict a keystone of this manuscript, I would encourage to extend the section in the introduction on this subject. In doing so, literature on the situation in Asia where human-elephant conflict is a considerable issue, might be added and improve the background information.


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: AFRICAN SAVANNA ELEPHANTS (LOXODONTA AFRICANA) AS AN EXAMPLE OF A HERBIVORE MAKING MOVEMENT CHOICES BASED ON NUTRITIONAL NEEDS
Review round: 1
Reviewer: 2

Output:
Basic reporting: The introduction sets up an interesting research question—the nutritional drivers of elephant movement on human-dominated landscapes—that could be of broad and cross-disciplinary interest. I commend the authors on identifying an important and interesting area for review. However, the paper was unfocused and left me unclear as to how the rest of the paper followed through with what was laid out in the introduction. The stated purpose of the study was to review previous work on elephant movement for mineral needs, and the ways in which elephants are modifying their movement in response to anthropogenic pressures. Crucially, the studies reviewed do not analyze elephant movement or habitat selection for minerals, nor how elephant movement for minerals is influenced by changing human pressures on populations. There were no search terms related to movement or habitat selection. Rather, a range of topics related to elephant nutrition are explored without transitions or previous mention in the introduction (e.g. cow/bull differences, activity budgets), that are better categorized as a discussion of elephant nutrition. This left me returning to the introduction again and again to remind myself what the goal was, and the aims laid out in the discussion conflicted with those in the introduction. I think the manuscript would benefit greatly from a more focused organization and a revision of search terms (there is a substantial body of literature on elephant habitat selection that was excluded).

As this was a review paper, I would like to have seen more detail in the results reporting on the literature search. At present the only detail is the number of articles found before inclusion and exclusion criteria were applied. What was the number after this process was applied? How do those studies break down by year, geographic region, topic, captive vs. wild, etc…? What were the trends found in the literature search regarding the research directions taken? What areas of research have not been addressed in the literature and are deserving of further study?

Without any context for the search results, it is hard to gauge the thoroughness of topics covered in the discussion. Certain sections rely very heavily on old literature, and I am left wondering whether these topics have been abandoned over recent years or whether they have simply been left out of the review for some reason? There are other cases in the manuscript where bold statements are made without any references, and other instances where references are used that do not appear in the reference list (e.g. Sienne et al. 2014).

Professional English was used throughout the manuscript, but the main point of many paragraphs was unclear and transitions between paragraphs lacking. Additionally, there were grammatical errors throughout the manuscript like mismatched subject-verb pairs (e.g. l. 138, ll. 327-328), missing definite articles (l. 74), misplaced/missing punctuation (e.g. l. 390, ll. 467-470, l. 616), incorrect word usage (e.g. should “partition” be “parturition” on ll. 302-303?, l. 521, l. 584), and inconsistent spelling (e.g. “savanna” or “savannah”? “mega-herbivore” or “mega herbivore”?). I think the manuscript would also benefit from a thorough read-through for sentence clarity. For example, the phrase “and their feeding strategies adopted” on l. 189 does not add anything to the sentence. Or on l. 571, “the drinking of water” can simply be “drinking”.
Experimental design: The search terms and databases that the authors used are stated, but the rest of the methods are not detailed enough and it is unclear how they affected the selection of literature reviewed. For example, one of the criteria for inclusion was that the article was available to the authors. What does this mean? How many articles were not available? If there are a large number of articles in this category I would think this would really affect the patterns you can derive from the literature.

Additionally, because the stated aim of the study is to review elephant movement in relation to minerals, “movement” and “habitat selection” should be terms included in the search. Asian elephants are discussed throughout the paper but “Elephas” is not a search term and therefore presumably not systematically reviewed.
Validity of the findings: The findings seem to be reflective of the studies reviewed but overall do not reflect the stated aims of the review.
Additional comments: l. 28: “The world’s natural ecosystem” is vague. There is no one world natural ecosystem.
ll. 29-30: This should be written as a list.
ll. 38-40: This point does not seem relevant to your larger framing. What does elephant capacity to alter their landscapes have to do with their altered movement as a result of anthropogenic activity? If the argument is that elephants are keystone species and their use as example species is therefore relevant to a range of other species, this should be stated.
ll. 47-50: What were the results of the systematic search after inclusion and exclusion criteria were applied? How did number of studies break down by year, geographical region, topic, etc…? What were the trends that you found in your search? What areas of research were glaringly missing from your search?
ll. 52-54: This sentence is redundant, as you have already stated the idea earlier in the abstract.
ll. 54-56: This review does not provide inference on predicting or mitigating human-elephant conflict.
ll. 56-57: This was already mentioned in the methods of the abstract and does not belong in the discussion.
l. 58: Generally, the introduction should start with broad context to set up the research question. As written it is a bit disjointed, with the stated aim of the paper expressed before the need for it is established. Reworking the introduction could focus on the general issue of access to resources across species on human-dominated landscapes, then narrow to elephants as a valuable case study, and finally lay out plans for the research question.
ll. 59-70: The abstract sets this up as a larger issue of wildlife populations being squeezed into smaller areas, and I think the introduction should be similarly structured. Elephants can then be brought in later in the introduction as a relevant case study.
l. 59: The paper discusses all three extant elephant species, so the emphasis should not only be Loxodonta africana but elephants generally if this paper is to retain discussion of the three species.
ll. 62-64: This sentence needs references.
ll. 66-67: This sentence is unrelated to the rest of the paragraph.
ll. 74-76: This statement needs a reference.
ll. 75-76: Again, I am unclear as to what the “world’s natural ecosystem” is.
ll. 77-80: Needs a reference.
ll. 80-82: Animals selecting habitat to meet their dietary needs is not something they adapt to do on human landscapes, it is something they have evolved to do generally. Perhaps what you are trying to say is that the way they go about this on human-dominated landscapes can present managers with new problems? Please clarify.
ll. 87-97: These objectives are not consistent with what is discussed in the rest of the paper.
ll. 101-103: This is an awkward sentence with which to end an introduction, and should probably be mentioned earlier to set up the need for your study.
ll. 129-134: Much more detail is needed here. How many studies were included in the final selection? How did the studies break down by topic, region, species, year? What were the trends in topics covered? Figures and tables would be very helpful here.
ll. 138-142: These aims are very different from those laid out in the introduction.
l. 143: Is this the introduction or discussion? Is it labeled incorrectly?
l. 143: It would be helpful for the first paragraph of the discussion (at minimum) to highlight the general trends found in the literature search. At present, the discussion reads as a collection of discrete and unrelated sections. A reworking of the discussion with a more logical organization would be helpful for readers.
l. 144: If both African species are a part of this review, forest elephants should be introduced earlier in the manuscript and savannah elephants should not be the sole focus in the title.
ll. 144-186: The relationship between activity budgets and your stated aims is unclear.
ll. 259-261: Again, if Asian elephants are included in this review they should be included systematically (i.e. in the search terms).
l. 264: This comes out of left field. What do equids have to do with this?
ll. 265-282: It would help to have some context for this section set up in the introduction, as it comes out of left field and is given considerable space in the discussion, which is a bit jarring. But more importantly, it is unclear what this section has to do with elephant movement related to minerals, or their movement on human landscapes.
ll. 268-270: Add reference.
l. 285-286: Add reference.
l. 286: What does this mean? African elephants grow tusks throughout their lives.
ll. 310-311: Add reference.
ll. 363-365: Rework this sentence for clarity.
ll. 373-402: The relationship between this paragraph and the larger idea of the paper is unclear.
l. 412, 421: What is Cn?
l. 415: What is Cot?
ll. 432-435: Add references.
ll. 500-502: Reference?
ll. 509-514: What does this have to do with movements for minerals?
ll. 542-544: Was this just speculation? What was the evidence they presented for this?
ll. 564-566: This seems very speculative.
ll. 592-593: Odd sentence.
ll. 594-596: Reference?
ll. 633-637: References?
ll. 668-670: This sentence is unrelated to the rest of the paragraph.
ll. 672-673: This claim is untrue. The reviewed work does not include elephant movement or habitat selection.
ll. 686-689: References?
Table 2: Kenya is not southern Africa.


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: AFRICAN SAVANNA ELEPHANTS (LOXODONTA AFRICANA) AS AN EXAMPLE OF A HERBIVORE MAKING MOVEMENT CHOICES BASED ON NUTRITIONAL NEEDS
Review round: 1
Reviewer: 3

Output:
Basic reporting: The manuscript was well written and clear.
This review is of interest to a broad audience, as well as providing an interdisciplinary perspective for the reasons behind elephant and other herbivore movements. To my knowledge, this field has not previously been reviewed and the information is important to conservationists, ecologists, and animal managers.
Experimental design: The organization of the beginning of this article was slightly confusing. The authors had subsections for the abstract and then again went through those subsections before digging into the information. I would suggest removing the small discussion section as it’s repetitive and renaming the Line 143 as Feeding Behavior rather than “Introduction” again.
The survey methodology seems mostly comprehensive, the only concern I have is that it was stated in Line 114 that the authors reviewed articles only that were available to them in full. I wonder what the restrictions were in their access to journals and how much was not reviewed due to lack of access. I am also surprised that "movement" was not included as a search term given the title and focus of this article. Although even with these slight concerns, it seems like significant literature was covered.
Validity of the findings: The literature reviewed supports the goals set out by the authors and they conclude with valid gaps and future directions.
Additional comments: This is a valuable review of the literature! Just a few edits and comments below:
Line 176 add “to” before adjust
Line 185 I think this was supposed to be dry season given the preceding text.
Line 212-213 Introduce the abbreviations in the previous sentence and you may want to quickly define “as-fed”
Line 343 I think if you define this abbreviation earlier in the text you won’t have to re-establish it here
Line 412 Define Cn or is this supposed to be Cu?
Line 421 is this supposed to be Cn?
Line 428 Need to define P as abbreviation for phosphorus


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: AFRICAN SAVANNA ELEPHANTS (LOXODONTA AFRICANA) AS AN EXAMPLE OF A HERBIVORE MAKING MOVEMENT CHOICES BASED ON NUTRITIONAL NEEDS
Review round: 2
Reviewer: 1

Output:
Basic reporting: Significantly improved. See attached file.
Experimental design: Clear structure, revisions made. See attached file.
Validity of the findings: Clarified. See attached file.
Additional comments: In my opinion the manuscript was significantly improved and there is a clear structure in it now.
Please find my comments in the PDF attached.


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: AFRICAN SAVANNA ELEPHANTS (LOXODONTA AFRICANA) AS AN EXAMPLE OF A HERBIVORE MAKING MOVEMENT CHOICES BASED ON NUTRITIONAL NEEDS
Review round: 2
Reviewer: 2

Output:
Basic reporting: The authors made changes to the introduction that clarified audience and motivation.
Experimental design: The authors made suggested improvements to clarify their methods and their citations. After the first revisions, I still think the organization of the review is unclear. I think to make it easier to follow, the authors should use a consistent presentation of the ideas following what they introduce as numbered list of objectives in the introduction and in lines 103-108. So they should either change those lists to follow how their paragraphs are presented or vice-versa. I also think the HEC paragraph that was added should either be relocated to a different part of the manuscript or should be better connected to the preceding paragraph. I currently don't see how it follows from the mineral needs of elephants. Do the authors want to introduce it as a type of feeding behavior? Or as a result of nutritional requirements?
Validity of the findings: The authors have presented evidence that supports their objectives and future directions are identified.
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: SUPPRESSION OF HESA MUTATION ON NITROGENASE ACTIVITY IN PAENIBACILLUS POLYMYXA WLY78 WITH THE ADDITION OF HIGH LEVELS OF MOLYBDATE OR CYSTINE
Review round: 1
Reviewer: 1

Output:
Basic reporting: The manuscript describes the effect of the disruption of hesA, which is part of the nitrogen fixation gene cluster of the bacterium Paenibacullus polymyxa, on nitrogenase activity. The authors show that the effect of the hesA disruption can be partially rescued by molybdate and sulfur source supplementation. The work is scientifically sound and the manuscript provides a complete description of methods and results. The findings are new and interesting, yet the manuscript can be significantly improved.

1. major comment: the introduction lacks sufficient introduction of the FeMoco biosynthesis pathway. The gene cluster is briefly mention, but existing knowledge about the role and interaction of the different components should be properly introduced. I have a similar comment about the discussion section. The new findings should be placed in context of the existing knowledge on the biosynthesis of the nitrogenase metal cofactors. The focus is now too much on only HesA and related proteins, not on the interplay with the other components of the FeMoco.
2. the text still contains a number of typographical errors, to list a few:
line 253: concentraion
line 281: excecpt
line 288: Furthwemore
line 307: genrally
line 338: affact
3. throughout the manuscript the authors express the molybdate concentration in nM, ranging from 3E1 to 3E8 nM. I strongly recommend to use suitable units: e.g. 30 nM instead of 3E1 nM, and 0.3 M instead of 3E8 nM. This will assist the reader in understanding the actual concentrations that have been used.

Minor comments below:
4. abstract: "will provide insight into the complex synthesis..". The authors can be more specific here. How does this discovery changed our current understanding of FeMoco biosynthesis?
5. line 60: "molybdenum cofactor (Mo-co)". It is worthwhile to introduce already here that Moco consists of the molybdopterin cofactor with molybdenum bound to its dithiolene moiety.
6. line 260: cysteine enhances the activity of the hesA deletion in the E. coli train containing the nitrogen fixation gene cluster up to a level which is similar to the activity with sulfate as a sulfur donor (see fig 6 and 7) at the same Mo level. I do not see this clearly described in the text.
7. line 266-268 and fig 7: all strains exhibit similar behaviour in response to the cystine concentration, with or without HesA. I am not convinced that this "confirms that hesA might be involved in sulfur transport like the function of MoeB".
8. line 316-319: I am not convinced that nitrogenase of the hesA mutant is so much higher with cysteine than with sulfate. In Fig 5 the scales and the color scheme of the bars are unfortunately different, but if I see correctly
9. line 319: what do the authors mean exactly that HesA is involved in cystine transportation? Does it reduce cysteine to cysteine?
10. discussion: I miss a proposed mechanism as part of the discussion. Clearly HesA is involved in S and Mo introductin into the FeMoco. Is it possible to place HesA functionally between the other components of the cofactor biosynthesis system that is present in this organism?
11: line 329: the authors comment on the presence of ModA(B)C. For most of the Mo concentrations that have been used active transport is likely not necessary. Furthermore, if the intercellular concentration of Mo is high, the transport system is likely not expressed.
12. line 337-340: It is interesting that HesA is apparently not involved in Moco biosynthesis, since this organism does not have MoeB (if I understood that correctly). Can the authors explain why this is not a problem for Moco biosynthesis?
Experimental design: The research question is clear and the experiments have been well designed and adequately described. It would be very interesting to measure the action of the HesA protein in-vitro, but this can be follow-up research.
Validity of the findings: The results are clear and the interpretation is overall sound. My main comment, as stated under (1) is that cystine and sulfate appear to have a similar effect on the nitrogenase activity. The authors report that cystine strongly enhances the nitrogenase activity of the hesA mutant, but this does not clearly follow from the data.
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: SUPPRESSION OF HESA MUTATION ON NITROGENASE ACTIVITY IN PAENIBACILLUS POLYMYXA WLY78 WITH THE ADDITION OF HIGH LEVELS OF MOLYBDATE OR CYSTINE
Review round: 1
Reviewer: 2

Output:
Basic reporting: The article is  written in mostly good English and uses clear, unambiguous, technically correct language. It does conform to professional standards of courtesy and expression. It has sufficient introduction and background to demonstrate how the work fits into the broader field of knowledge and relevant prior literature is appropriately referenced. The structure of the article is in a format of ‘standard sections’. This manuscript is ‘self-contained,’ represents an appropriate ‘unit of publication’, and includes results relevant to the hypothesis.
Experimental design: This manuscript provides evidence that hesA in P. polymyxa is involved in the pathway from Mo and S transport to synthesis of Fe-Mo-co. The experiments are well designed and the question is interesting.. The data in this manuscript provide evidence that in both P. polymyxa and in E. coli expressing nif genes, loss of nitrogenase activity in a hesA mutant can be partly overcome by increasing levels of Mo or cysteine, but not sulfate. The methods for nitrogenase activity are inadequate. While details are not necessary, the fact that it was apparently done by measuring acetylene reducton to ethylene by GC should be indicated.
Validity of the findings: The data in this manuscript are robust, statistically sound and controlled. and they provide evidence that in both P. polymyxa and in E. coli expressing nif genes, loss of nitrogenase activity in a hesA mutant can be partly overcome by increasing levels of Mo or cystine, but not sulfate. The fact that a hesA mutant has no effect on nitrate reductase that uses Mo-co indicates that hesA is specifically involved in FeMo-co biosynthesis. While the data generally support the conclusions there is nothing in this manuscript that provides any information on how HesA is involved in synthesis of Fe-Mo-co.
Additional comments: Fig. 1 provides no information on the degree of similarity of the hesA genes. Perhaps the authors could create a table showing % similarly or provide a phylogenetic tree.

Fig 8 is unnecessary. The numbers should simply be reported in the text.

Line 133. “Erythromycin” should be “chloramphenicol.”

Line 195. “Respectatively” is misspelled

Lines 236 and 238 change “than” to “of”.

Lines 240 and 241. Complemented is not the correct word when a different gene is used. Here is better wording:  “In addition, we tried to complement the ΔhesA mutant with E. coli moeB and found that the expression of moeB in the mutant did not improve nitrogenase activity (Fig. 5). In fact, the nitrogenase activity in the ΔhesA mutant expressing moeB declined when the concentrate of cystine exceeded 1.0 mM.“

Line 253. Rewrite as follows: “The D-O strain required 10 times as much molybdate to achieve the level of activity of the E.  coli 78-7 strain. The P. polymyxa hesA gene could complement the D-O strain and restore the activity of the hesA deletion strain to that of the E. coli 78-7 strain.

Line 256. The meaning of this sentence is not clear. I do not understand what “restrain” means here.

Line 288. I  do not think that the Mitschke et al. 2011 reference provides any direct information that hesA  is required for nitrogenase. In fact Borthakur et al. 1990 indicates that loss of hesA results in only about a 50% loss of nitrogenase in Anabaena.


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: SUPPRESSION OF HESA MUTATION ON NITROGENASE ACTIVITY IN PAENIBACILLUS POLYMYXA WLY78 WITH THE ADDITION OF HIGH LEVELS OF MOLYBDATE OR CYSTINE
Review round: 2
Reviewer: 1

Output:
Basic reporting: Acceptable.
Experimental design: Acceptable.
Validity of the findings: Valid.
Additional comments: An improved manuscript that adequately addresses most of the concerns of the reviewers.


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: TOTAL INCOMBUSTIBLE (MINERAL) CONTENT OF CHERAX QUADRICARINATUS DIFFERS BETWEEN FERAL POPULATIONS IN CENTRAL-EASTERN AUSTRALIA
Review round: 1
Reviewer: 1

Output:
Basic reporting: The manuscripts is based on a study of limited importance, though it has its merits as part of the freshwater crayfish research. My suggestion is a major revision, and compacting the manuscript in the format of a short note.
Experimental design: Nothing fundamentally wrong with the experimental design. I would have wanted to read a rationale for why the authors choose these sampling sites.
Validity of the findings: I found the data insuffienctly presented, with at least these aspects to be improved 1) the background data from the sampling sites should include sufficient water quality details, including Ca and other cations relevant for calcium uptake; 2) details regarding population density, growth rates, etc., which could explain some of the differences been discovered; 3) Lake Moogerah sample should be omitted (N=2!) or statistically treated to fit the overall sampling intensity, with the same done for other sites, too, if found relevant. This is due to the sample size differences. This should be evident based on the Fig. 4; 4) Fig. 3 does not seem relevant, as it only indicates that this set of data does not explain any relationship in the data set. This could be treated in body of the text; 5) is Fig. 2 combining the whole data set, i.e., samples from different locations? If yes, then this pooling of the data should be better discussed. If not, then what is in Fig. 2?; 6) Table 1 presents climatic details, been obtained from different periods of time. Do the differing data collection periods affect the variation seen in the data? Could there be time period related artifact created here?
Additional comments: I would recommed compacting the manuscript and making into a short note. Some suggestions regarding data presentation improving presented in the boxes above. After working with data volume and presentation, the authors should rework with the Discussions section, as there should now be more food for speculations.


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: TOTAL INCOMBUSTIBLE (MINERAL) CONTENT OF CHERAX QUADRICARINATUS DIFFERS BETWEEN FERAL POPULATIONS IN CENTRAL-EASTERN AUSTRALIA
Review round: 1
Reviewer: 2

Output:
Basic reporting: Majority of the article is well written, using good grammar with professional English language. However, the title of the article is broad and verbose. It can be easily modified and can be focused on the research question.
Introduction is well written but is out of focus. It reads like a good literature review on the basic ecology of the freshwater crayfish but does not say enough on the main aim of this article which is difference in ash (mineral) content of two crayfish populations.
Some of the terms like ‘physiochemical characteristics of waterbodies’ and ‘physiology of crayfish’ are very broad terms and are not part of this research. The mineral content of the species and recording of pH and temperature do not qualify for physiology and physiochemical characters.
The introduction section needs to be reduced to forty percent of its length by putting greater focus on the research question and justifying this research.
Experimental design: Experimental design of this research is simple and does not need much elaboration. However, more information on the number and time of crayfish captured from each location will be helpful. What was the moult stage of crayfish captured? The mineral content of the crayfish is dependent on the moult stages.
Validity of the findings: The findings of this research are good and valid. Our knowledge of chemistry tells us that pH has a profound impact on minerals, mainly on their biological availability.
We also know crustaceans, including freshwater crayfish are highly adaptive and over a period of time they can thrive very well in harsh environmental conditions.
Freshwater crayfish in Western Australia are also known to live in acidic waters filled in discarded mining voids.
Additional comments: Table 1 is irrelevant as it describes the location and temperature data recorded from the weather station.
	The impact of these air temperatures on the temperatures of the sampled water bodies is not clear. Though coordinates are provided, it is hard to estimate the distance from the weather station to the sampled waterbodies. Moreover, as temperature is influenced by the volume and depth of waterbodies, the presence of table 1 does not add, in anyway, the science to this article. Therefore, please delete table 1.
 Please modify table 2. pH is dependent on the sampling time of the day and natural productivity of the waterbody. Please provide the time when pH was recorded and any information on the presence of life (micro algae, plants, zooplanktons etc.) in these waterbodies.
	It seems that a total 162 animals were trapped. Why sample size  from every waterbody is not provided. It would be easy to understand if data are presented in the format of  ‘mean with SE’ and with n from each waterbody.
Figure 1 – delete. The reference to native range and distribution of red claw should be sufficient in the text.
Figure 2 is relevant. However, legend needs more details. N?
Figure 3 – delete. As there was no relationship between length and mineral content, there is no need to include this figure.
Figure 4 is relevant and is directly related to the theme of this article.

Discuss also hovers along with those discussion points which are not related to the aim of this research. The aim of this research should focus on the variation in the mineral contents of the different populations of the freshwater crayfish and its relationship with the pH of the waterbodies (we don’t know the pH of all water bodies). Only then, it can include some speculations about the relevance and justification of the research to impacts of translocation and not in reverse direction.
Conclusion is well stated but it does incorporate some information which is of common knowledge and does not come from this research.
 Please spend some more time in revising this article and try to be focused on the research question. Also include some more references from Western Australia, where it is reported that the local crayfish population has made home to various water bodies very different from where they originally come from.


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: TOTAL INCOMBUSTIBLE (MINERAL) CONTENT OF CHERAX QUADRICARINATUS DIFFERS BETWEEN FERAL POPULATIONS IN CENTRAL-EASTERN AUSTRALIA
Review round: 1
Reviewer: 3

Output:
Basic reporting: The writing in this manuscript is on the whole clear and succinct. I especially appreciate the engaging tone and varied sentence structure, which easily guides the reader along.

Here are some comments, provided in the structure suggested by PeerJ:

Professional English:

Please provide appropriate punctuation for a few instances of run-on sentences (eg lines 33, 126, 182, 190, 195, 204).

Professional article structure:

The organization of some sections would benefit from some reworking or addition of information Of most importance to rectify are the introduction and discussion. The introduction does not include a broad background section in which to place this piece of research. Based on the data presented, I would have appreciated an introduction to the topic of nonnative species and means by which they persist in conditions unlike that of their native range, including specific examples. There is also extraneous information presented in the introduction that I did not find useful, such as climate data in parts of Australia. The discussion could be more developed to both create a better flow of ideas; as is, there are some jumps in topic between paragraphs.

L51: Please begin with a more general introduction for the research that is to be presented. This introduction, for example, might touch upon ways other organisms have found success in nonnative habitats, despite substantial differences in abiotic or biotic factors from their home ranges. This seems like the main theme of your paper. It might also be worthwhile to discuss what benefits crayfish or other crustaceans receive from producing mineralized exoskeletons (e.g. predator defense) so that you may explain the functional importance for your findings later.
L60-64: As this paragraph stands, the specific link to the research is unclear. Do these weather conditions control the water parameters of the lakes?

L134-135: Again, it would be useful if there was more buildup to this objective, especially in relation to why one might expect there to be differences in mineralogy across these different water bodies and why mineralogy was chosen as the defining feature of these different populations to study.

L178-179: The sample size is more appropriate for the methods.

L162-167: Please incorporate this in the introduction, as the additional information about the lake substratum forms part of background information

Please consider building larger paragraphs in the results (lines 182- lines 200) and discussion (lines 254-270) to better construct a flow of ideas.

Literature references and background:
There has been a great body of literature built up around the structure and composition of crustacean exoskeletons over the last few decades. The literature cited in your discussion would be bolstered by the addition of some of these works. As such, some of the main information cited is backed by a textbook, not a primary piece of literature. I would recommend reading a few of the classics for the best overview, such as the Raabe papers I cited; Bentov has some well-written articles on some specialized regions of the crayfish exoskeleton too.

L130: Is this study related to this research? If so, please cite it fully. If not, consider removing this extraneous information.

L236-238: The exoskeleton of crayfish, like most crustaceans, is not primarily mineral; instead, it is based of chitin and protein fibers impregnated with calcium carbonate and calcium phosphate (Bentov et al., 2012; Raabe et al., 2006; Raabe et al., 2005). As such, calcium is likely not the most important element; an exoskeleton can still harden to some degree after molting through the tanning process. Consider rephrasing to state that it is an integral exoskeleton element without overstating its importance.

L247-257: Please make the connection between exoskeleton structure and composition to provide the relevance for including this study.

L246: This is a great spot to discuss one of the major impediments to calcification at lower pHs that has not yet been addressed in this manuscript: the reduced availability to carbonate ions. As pH decreases, the carbonate system shifts from a predominance of carbonate to bicarbonate and then carbonic acid. Crustaceans are believed to have some mechanisms to procure carbonate ions at the site of calcification, but the small amount available externally may be playing a role in the lower amounts of calcification at lower pHs observed here.

Figures and tables:
Table 1: Consider cutting. These data have not established relevance to this study.

Table 2: Please note what scale pH is measured in. It would also be useful to know what pH ranges this species experiences in its native habitat, either provided here in this table or in the text.

Figure 1. As this research focuses on the locations where these crayfish are established outside of their range, this figure could be improved by also showing the study locations to give readers not only a sense of the feral extent of these crayfish but highlight the spatial range of locations studied.

Figure 2. It is a bit unusual to see a histogram in manuscript, and this might not be necessary because readers are able to get a sense of the number of crayfish with a particular mineral composition in both figures 3 and 4.

Figure 3 and 4: Specify what mineral content is measured here, as other minerals might be magnesian calcite, for example, which was not measured. Also, please state the major finding or trend of the analysis for both Figure 3 and 4 in the caption. For Figure 4, it would also be useful to have an asterisk or some other symbol to indicate significance to the readers quickly.
Experimental design: Despite the numerous positive attributes of the manuscript, aspects of the experimental design were of considerable concern, which ultimately led to my decision. The biggest source of my uncertainty is on the measurement of calcium presented here.

High technical standard of investigation:
In the study of crustacean exoskeleton composition, loss-by-ignition is not a common methodology. Common methods for elemental composition are energy-dispersive x-ray spectroscopy (EDX or EDS) for atomic or weight percent (deVries et al., 2016; Taylor et al., 2015; Wu and Zhou, 2011) as well as inductively-coupled plasma mass/atomic/optical emission spectrometry (ICP-MS or ICP-AS or ICP-OES) for exact concentrations (Eriander et al., 2015; Gravinese et al., 2016; Long et al., 2016; Page et al., 2016). Atomic adsorption spectrophotometry is also accepted (Findlay et al., 2010; France, 1987; Huner et al., 1978; Malley, 1980; Small et al., 2010; Wickins, 1984).

In this manuscript, it is unclear how the amount of calcium is determined from ash weight of the whole crayfish samples burned at one temperature. I am unable to access to the book used here as a reference, so I have looked to a small selection of primary literature for background on this method. It appears it is somewhat commonly used to analyze the organic carbon content and total carbon content sediment and soil. The sample is burned at around 500 deg C is designed to release the organic carbon, although some work has shown that there are multiple factors that can lead to some of that material remaining, necessitating a hotter exposure (Gallardo et al., 1987) or an exposure for at least 2.5 hours (Heiri et al., 2001). After organic matter is burned off and the sample weighed, the temperature is increased to around 900 deg C, which causes loss of the carbonates, and the sample must be weighed again to calculate this carbonate content (Dean Jr, 1974; Heiri et al., 2001). It is not described how carbonate (or, more specifically, how calcium from the carbonate amount) is determined in this research, but it appears that the data are presented with the assumption that the material left after an exposure of one hour at 500 deg C is 100% carbonate, which may not be true given that 1) the organic content is likely not fully burned off at this duration and temperature, and 2) the second burn exposure at 900 deg C and weighing was not carried out to specifically target carbonate compounds.

For biological samples where ash content or thermogravimetric analysis is used for one part of the analysis,  additional methods are undertaken to determine elemental composition (Boßelmann et al., 2007; France, 1987; Monti et al., 2008; Rupérez, 2002), suggesting that burning off organic material is not enough to determine the amount of minerals present in the sample.

Furthermore, the data presented give me pause. The whole animal was combusted (or a homogenous sample if the animal was too large), and it seems unreasonable that, on average, this species of crayfish is comprised of ~50% mineral (Figure 4). In the crayfish species Orconecfes virilis, one study finds 12-17% of the carapace (where mineral is likely to be concentrated) is calcified (Malley, 1980), whereas later work finds 20-22% of the carapace and just 7-9% in the whole abdomen is comprised of calcium (France, 1987).  In Procambarus clarkii, intermolt carapace calcium is 24% by weight (Huner et al., 1978).

To justify the methods presented as a way to accurately quantify the amount of calcium in a sample, please cite any examples where this methodology has been applied to biological samples, in particular whole crustaceans. Please write more details on this methodology, including how it is known that the result of one hour at 500 deg C results in carbonate alone, walk readers through the calculation of Ca from the measurement of carbonate, and describe how it is known that the mineral is CaCO3 rather than the sometimes-used MgCO3. Alternatively, if more work took place that negates these criticisms, provide more detail in the methods to explain these steps (eg digesting the ash in acid and performing atomic adsorption spectrophotometry).

This manuscript would also benefit by the addition of environmental data to describe the carbonate chemistry of the lakes to better support the relevance of the findings. The authors presented pH data at the site of collection. It is unclear if pH was sampled multiple times, but the pH would be better characterized with multiple measurements to capture the likely conditions under which these exoskeletons formed and mineralized.  However, one other component of the carbonate system must also be measured (eg total alkalinity, pCO2, DIC), in addition to salinity and temperature, to accurately quantify the carbonate chemistry of the lake (Dickson et al., 2007). This will lend more support to the argument that lake conditions are the driving mechanism behind differences in crayfish calcium content. The crayfish biomineralization process may certainly be sensitive to the concentration of hydrogen ions in the external environment, but the saturation state of calcium carbonate minerals is also likely to play a role, although this cannot be determined from pH measurements alone.
Validity of the findings: Another concern of mine is that this research does not demonstrate a direct effect of pH on the differences in mineralization of the crayfish, although this is a focal topic of discussion. The difference in mineralization may be due to lake temperature, another undiscovered biological or abiotic factor, or simply different selection pressure for the crayfish in this lake. The relationship between lake pH and mineralization is purely speculation, but this might not come across to a casual reader, eg the title of this manuscript states that the pH level of this habitat has an effect on this species. Please be a little more restrained and limit the potential correlation between pH and mineralization to the discussion as one potential explanation for the results. Laboratory experiments that hold these crayfish in water of different pHs through at least one molt cycle would allow for a better explanation of these field findings.

Alternatively, consider refocusing the manuscript as a study on the differences in mineralization that one species can might achieve in the field; this would be a worthwhile addition to the crustacean exoskeleton field, as some researchers (most commonly engineers) who study the exoskeleton sample a single specimen as a representative of the whole species! Demonstrating spatial differences in exoskeleton composition would provide beneficial background for many researchers.

L226: There hasn’t been a demonstrated cost to a reduction in calcification. Less mineralization can reduce the density of the animal, for example, allowing it to achieve greater velocity through tail-flipping and avoid predators better in that regard. This study does not address the functional impacts of a change in mineralization, and so a hypothesis that there is a negative impact of reduced mineralization should be framed as such.

L230-231: For this research, it might be worthwhile to either discuss the possibility or reframe the results in the context that the reason Lake Ainsworth crayfish might have reduced calcium levels for one of two reasons: 1) as the authors state, this is the only lake that lands on the acidic side of the pH scale (simply chemistry, [H+] > [OH-], or 2) this pH level might simply be outside of the calcification tolerance of this species (biological control on the process of mineralization). In my research field, we see changes in calcification due to decreasing of ocean pH, although the oceans will never be acidic; instead, the seawater pH has moved outside of a range of tolerance.
Additional comments: Dear authors,

This research represents a timely focus on the adaptability of a nonnative crayfish species to multiple lakes with various abiotic conditions. The implications are well-described and provide a convincing argument for the study of characteristics that allow some organisms to adapt to a wide range of conditions.

Provided below are some more general comments as well as the literature references that I cited in my response.

Introduction
L66-70: Are these predators of this crayfish species? If not, I would recommend cutting theses lines. If yes, this might fit well with a discussion of how hard exoskeletons can help crustaceans deter biting predators (although there may be limited options for escape with such large predators!)

L69: In my opinion, this line seems a bit colored by the human experience rather than fact. Crayfish are a successful group of crustaceans and have evolved quite a few methods to avoid predation by large predators (eg the tail flip, the claws, coloration), and so they might not find these environments very challenging at all! I would think it is less likely to ruffle the feathers of any readers by changing this phrasing.

L81-82: Change the word “countries,” as the locations listed are not examples of countries.

Results
Line 194: It would be helpful to have either the range of calcium across locations reported here or the full means +/- sd for each location

Discussion
L202-203: This line does not properly highlight the novelty or contribution of this research. Please reframe to show these results.

L284-285: Here, I do not follow the logic of these species being a source of calcium. Would they not also have difficulty maintaining levels of calcium carbonate too if their mutual environment was a limiting factor?

References:

	Bentov, S., Zaslansky, P., Al-Sawalmih, A., Masic, A., Fratzl, P., Sagi, A., Berman, A. and Aichmayer, B. (2012). Enamel-like apatite crown covering amorphous mineral in a crayfish mandible. Nature communications 3, 839.
	Boßelmann, F., Romano, P., Fabritius, H., Raabek, D. and Epple, M. (2007). The composition of the exoskeleton of two crustacea: The American lobster Homarus americanus and the edible crab Cancer pagurus. Thermochimica Acta 463, 65--68.
	Dean Jr, W. E. (1974). Determination of carbonate and organic matter in calcareous sediments and sedimentary rocks by loss on ignition: comparison with other methods. Journal of Sedimentary Research 44.
	deVries, M. S., deVries, M. S., Webb, S. J., Tu, J., Cory, E., Morgan, V., Sah, R. L., Deheyn, D. D. and Taylor, J. R. A. (2016). Stress physiology and weapon integrity of intertidal mantis shrimp under future ocean conditions. Scientific Reports 6, 38637.
	Dickson, A. G., Sabine, C. L. and Christian, J. R. (2007). Guide to best practices for ocean CO2 measurements. Sidney, BC: North Pacific Marine Science Organization.
	Eriander, L., Wrange, A.-L. and Havenhand, J. (2015). Simulated diurnal pH fluctuations radically increase variance in—but not the mean of—growth in the barnacle Balanus improvisus. ICES Journal of Marine Science: Journal du Conseil, fsv214.
	Findlay, H. S., Kendall, M. A., Spicer, J. I. and Widdicombe, S. (2010). Post-larval development of two intertidal barnacles at elevated CO2 and temperature. Marine Biology 157, 725-735.
	France, R. L. (1987). Calcium and trace metal composition of crayfish (Orconectes virilis) in relation to experimental lake acidification. Canadian Journal of Fisheries and Aquatic Sciences 44, s107-s113.
	Gallardo, J., Saavedra, J., Martin‐Patino, T. and Millan, A. (1987). Soil organic matter determination. Communications in soil science and plant analysis 18, 699-707.
	Gravinese, P. M., Flannery, J. A. and Toth, L. T. (2016). A Methodology for Quantifying Trace Elements in the Exoskeletons of Florida Stone Crab (Menippe mercenaria) Larvae Using Inductively Coupled Plasma Optical Emission Spectrometry (ICP–OES): US Geological Survey.
	Heiri, O., Lotter, A. F. and Lemcke, G. (2001). Loss on ignition as a method for estimating organic and carbonate content in sediments: reproducibility and comparability of results. Journal of paleolimnology 25, 101-110.
	Huner, J. V., Kowalczuk, J. G. and Avault, J. W. (1978). Postmolt calcification in subadult red swamp crayfish, Procambarus clarkii (Girard)(Decapoda, Cambaridae). Crustaceana 34, 275-280.
	Long, W. C., Swiney, K. M. and Foy, R. J. (2016). Effects of high pCO2 on Tanner crab reproduction and early life history, Part II: carryover effects on larvae from oogenesis and embryogenesis are stronger than direct effects. ICES Journal of Marine Science: Journal du Conseil 73, fsv251.
	Malley, D. (1980). Decreased survival and calcium uptake by the crayfish Orconectes virilis in low pH. Canadian Journal of Fisheries and Aquatic Sciences 37, 364-372.
	Monti, A., Di Virgilio, N. and Venturi, G. (2008). Mineral composition and ash content of six major energy crops. Biomass and Bioenergy 32, 216-223.
	Page, T. M., Worthington, S., Calosi, P., Stillman, J. H. and Browman, H. e. H. (2016). Effects of elevated p CO2 on crab survival and exoskeleton composition depend on shell function and species distribution: a comparative analysis of carapace and claw mineralogy across four porcelain crab species from different habitats. ICES Journal of Marine Science 74, 1021-1032.
	Raabe, D., Romano, P., Sachs, C., Fabritius, H., Al-Sawalmih, A., Yi, S. B., Servos, G. and Hartwig, H. G. (2006). Microstructure and crystallographic texture of the chitin–protein network in the biological composite material of the exoskeleton of the lobster Homarus americanus. Materials Science and Engineering: A 421, 143--153.
	Raabe, D., Sachs, C. and Romano, P. (2005). The crustacean exoskeleton as an example of a structurally and mechanically graded biological nanocomposite material. Acta Materialia 53, 4281--4292.
	Rupérez, P. (2002). Mineral content of edible marine seaweeds. Food chemistry 79, 23-26.
	Small, D., Calosi, P., White, D., Spicer, J. I. and Widdicombe, S. (2010). Impact of medium-term exposure to CO2 enriched seawater on the physiological functions of the velvet swimming crab, Necora puber. Aquatic Biology 10, 11-21.
	Taylor, J. R. A., Gilleard, J. M., Allen, M. C. and Deheyn, D. D. (2015). Effects of CO2-induced pH reduction on the exoskeleton structure and biophotonic properties of the shrimp Lysmata californica. Scientific Reports 5, 10608.
	Wickins, J. (1984). The effect of hypercapnic sea water on growth and mineralization in penaied prawns. Aquaculture 41, 37 - 48.
	Wu, Z. and Zhou, F. (2011). Structure and mechanical properties of pincers for freshwater lobster. Science China Technological Sciences 54, 650-658.