No evidence for population-level benefits of polyandry in sharks and rays

Joel H. Gayford; Estefanía M. Flores-Flores

doi:10.1371/journal.pone.0308141

Peer Review History

Original SubmissionMarch 1, 2024
11 Jun 2024 Decision Letter - Stefan Schlatt, Editor PONE-D-24-08235No evidence for population-level benefits of polyandry in sharks and raysPLOS ONE Dear Dr. Gayford, Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process. It was extremely difficult to find reviewers for this manuscript. Finally I received very constructive comments. The paper needs major revision but has potential to be accepted after carefuly consideration of the reviewers concerns. Please submit your revised manuscript by Jul 26 2024 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. 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The PLOS ONE style templates can be found at https://journals.plos.org/plosone/s/file?id=wjVg/PLOSOne_formatting_sample_main_body.pdf and https://journals.plos.org/plosone/s/file?id=ba62/PLOSOne_formatting_sample_title_authors_affiliations.pdf. 2. Please note that PLOS ONE has specific guidelines on code sharing for submissions in which author-generated code underpins the findings in the manuscript. In these cases, all author-generated code must be made available without restrictions upon publication of the work. Please review our guidelines at https://journals.plos.org/plosone/s/materials-and-software-sharing#loc-sharing-code and ensure that your code is shared in a way that follows best practice and facilitates reproducibility and reuse. Additional Editor Comments: The authors have compiled an interesting study on the role of polyandry in sharks and rays. I agree with both reviewers that the study is of value but has also significant limitations. Both reviewers make constructive comments and recommendations for revision. I am optimistic that after point-by-point review and appropriate revision of the manuscript, it will be a useful reference and acceptable for publication. [Note: HTML markup is below. Please do not edit.] Reviewers' comments: Reviewer's Responses to Questions Comments to the Author 1. Is the manuscript technically sound, and do the data support the conclusions? The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented. Reviewer #1: Partly Reviewer #2: Partly ******** 2. Has the statistical analysis been performed appropriately and rigorously? Reviewer #1: Yes Reviewer #2: No ****** 3. Have the authors made all data underlying the findings in their manuscript fully available? The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified. Reviewer #1: Yes Reviewer #2: Yes ****** 4. Is the manuscript presented in an intelligible fashion and written in standard English? PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here. Reviewer #1: Yes Reviewer #2: Yes ******** 5. Review Comments to the Author Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters) Reviewer #1: The authors present an MS where they evaluated the possible benefits of polyandry at the population level in elasmobranchs. In general, it is an interesting article, however, currently, there is a consensus that a mating system is not necessarily better than others and the costs and benefits they offer are circumstantial. I mentioned this because the authors seem to part from this idea. I recommend reading some articles on this matter: Karl 2008 (DOI 10.1111/j.1365-294X.2008.03902.x), Lotterhos 2011 (DOI 10.1111/j.1558-5646.2011.01249.x), and Stephens & Sutherland 2000 (Chapter 9 in the book Vertebrate Mating Systems). I think that the methodology to abord this idea is adequate, in this sense, the article could give more emphasis to the multi-model approach they use to put this idea to test. What I do consider worth exploring in the discussion in more depth is how the benefits of polyandry and monogamy together can positively influence populations. To help the authors, I will try to give comments throughout the document in such a way that it can be useful to improve the MS. Abstract Lines 27-28. In this sentence, authors should specify this in the elasmobranch group, I suppose that’s what they mean. Line 30. This is plural, those are evidence to each effect. Lines 32-35. This sentence is so complex, that it has a justification and objective, this became too confusing for an abstract. I suggest restructuring in two sentences. Lines 37-41. I suggest restructuring this sentence because it sounds contradictory to the objective in the abstract. Also, it sounds a little catastrophic when you said We fail! I recommend this…. Results showed that both genetic monogamy and polyandry have evolved multiple times independently….and in biological conditions. Lines 39-41 and 42-43. I think that this idea has been discussed in some articles. Karl in 2008 debated this idea and he demonstrated that monogamy is not always a maladaptive strategy. For its part, Lotterhos 2011 also refuted this idea with a model, which showed that any adverse effect derived from polyandry is attenuated by long generation times. Kvarnemo's 2018 observations about monogamy suggest that this cannot be a maladaptive strategy since it is present in many groups, even if its benefits are not in sight. Introduction Line 56. “rampant polyandry” how can I interpret it? Line 62. Add in parentheses, revised in 10. Because it is a single cite of information in this sentence and it is controversial. Line 65. I have a conflict with these cites (10-11). Although one of them is proposed for the animal kingdom, in general, it is necessary to think about the peculiarities of the elasmobranch group. My main conflict is in the citation of Simmons 2001 since he bases his arguments on insects. Please, you need to consider this for vertebrates and, particularly in elasmobranchs. Line 85. What do you mean by “unwanted mating attempts”? Lines 91-94. You need to cite this sentence. Lines 101-103. This sentence reflects that there are many mating systems and not just polyandry and monogamy, what would those be? The authors assume that readers understand the limitations of mating system studies in elasmobranchs, it seems to me not necessarily. By this, I mean that polygyny is very feasible in this group, although it is extremely difficult to verify. Methodology Lines 120-121. I agree that there is no best form to get a value of MP frequency for a species, however, it cannot reflect the actual mating system in species that have geographical variations, or seasonal variation. Also, the sample size is an important factor influencing the MP frequency in different studies for the same species, along with the resolution power offered by the different molecular tools employed. I suggest adding this in the limitations section, or better, stating those understandable limitations right after the methods. Lines 123-125. Assuming this, authors need to discuss it in species with geographical variation in the MP. Lines 131-133. I invite to authors to read the articles before mentioned. I consider that it is not reflected in the introduction. Results Table 2. This table is unnecessary. I suggest sending it to supplementary materials and citing it in this part. Lines 187-189. I’m not familiar with the analysis, however, looking at the tree, I think the analyses give a lot of weight to the MP value. I’m concerned that in some cases, such as M. californicus, the sample size is too low to consider real genetic monogamy, since a particularity of this work is possibly collecting small females with a low probability of observing MP. In this case, It can be an effect of the sample size. Discussion Lines 206-209. These ideas should be expressed in the abstract and of course in the introduction. Lines 220-222. I’m not sure if this is correct according to the abstract of Dibattista et al. 2008. In this abstract, they said…” We find that offspring from polyandrous litters did not have a greater genetic diversity or greater survival than did the offspring of monandrous litters”. This sentence is contrary evidence. Lines 225-228. This idea is correct and is the best of all paper. This idea has been discussed. I suggest to the authors redirect the justification of their article considering their methodology. Lines 239-241. Using the average MP in a species cannot reflect the real mating system. Lines 246-248. Please, read to Stephens & Sutherland 2000, they had already discussed it and explained the Allee effect in this context. Lines 248-251. I do not agree. Since the model was not significant, I think the recurrent MP is not necessarily one adaptive peak. In this sense, this sentence is contradictory to the last sentence. Also, we need to consider that there are few studies to evaluate the mating system in the Elasmobranchii clade, thus this apparently adaptive peak can be skewed due to limited publications. Limitations Lines 264-266. Excellent! Authors need to moderate some previous sentences according to this section. Conclusions Lines 282-283. I think this is not demonstrated with your results. Reviewer #2: The potential link between multiple paternity, sexual selection and population viability is an important and general one, and I agree with the authors that this taxonomic group is a potentially useful model system in which to study it. That being said, I found it a little difficult to know what to conclude from this study. In principle I think it is important that negative findings are published, but I do have concerns as to whether the study really had sufficient power to test the hypothesis in question. To be fair to the authors, they are quite open about the limitations of the dataset in their discussion, so on balance I think I would be in favour, but first would like to see several more minor points addressed: Line 117: The data are presented as coming form the existing literature, but ca. 80% come from a single source. For that reason, I think it would be appropriate to present already in the Introduction the potential overlaps and novel aspects relative to this previous study. 143: It’s unclear to me why conservation status was coded quantitatively, rather than adopt a different analysis approach for this variable? Linear regression doesn’t feel like the most appropriate approach here. 173-177: Given all of these “relationships” are non-significant, I don’t think it is very meaningful to discuss which slopes are positive and which are negative; all you can reliably conclude is that none could be distinguished from zero. 200: on the face of it, purging would tend to reduce genetic diversity rather than increasing it - maybe take a bit more space to explain this point? 219: I understand you wished to use these investigated variables as proxies for extinction risk, but given you only look at extant species in this analysis I think this might be slightly overstated here. 244: the argument that both very high and very low polyandry evolves frequently in this group seems to support the approach of Lamarca et al.? I do think there is a real risk that using only one estimate of MP per species gives a falsely precise impression, since this presumably varies a lot from population to population. To be fair, this point is acknowledged later in the discussion, but is there scope to quantify this to give an idea about the scale of the problem? for how many species did you average across multiple populations? Table 3: please provide per analysis sample sizes, rather than just saying these varied. I also saw no sign that you accounted for multiple hypothesis testing here - these are essentially 9 different tests of the same underlying hypothesis, so there ought to be some control of the global false positive rate. Given all 9 are non-significant this doesn’t really matter in practice, but in principle it’s an issue that could at least be acknowledged. A few small typos/errors to correct: 36: through not though 56: for me rampant has potentially negative connotations, consider replacing with something more neutral (widespread?) 88: cost of mating 113: consequently 118: reference formatting 130: reference formatting 153: series of 259: missing word? ******** 6. 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Revision 1
11 Jun 2024 Author Response We thank the editor and reviewer for their time spent on this manuscript. We are very grateful for both of your comments, and believe that they have greatly improved the quality of the paper. Please find detailed responses to comments below. We hope that you find the changes made sufficient to consider acceptance of the manuscript, as we have to the best of our abilities incorporated all changes suggested by the reviewer into the text. Reviewer 1 Comment: The authors present an MS where they evaluated the possible benefits of polyandry at the population level in elasmobranchs. In general, it is an interesting article, however, currently, there is a consensus that a mating system is not necessarily better than others and the costs and benefits they offer are circumstantial. I mentioned this because the authors seem to part from this idea. I recommend reading some articles on this matter: Karl 2008 (DOI 10.1111/j.1365-294X.2008.03902.x), Lotterhos 2011 (DOI 10.1111/j.1558-5646.2011.01249.x), and Stephens & Sutherland 2000 (Chapter 9 in the book Vertebrate Mating Systems). I think that the methodology to abord this idea is adequate, in this sense, the article could give more emphasis to the multi-model approach they use to put this idea to test. What I do consider worth exploring in the discussion in more depth is how the benefits of polyandry and monogamy together can positively influence populations. Response: Thank you for your comment. We have read the papers you suggest and cited them where relevant in the manuscript. Comment: Lines 27-28. In this sentence, authors should specify this in the elasmobranch group, I suppose that’s what they mean. Response: Thank you for your comment. This sentence is general, and is referring to the entire animal kingdom. Several papers (including reference 10 in our list) explain how the theoretical consequences of mating system variation are applicable across animal life, and that the biological contexts that could result in different benefits or costs to polyandry or monogamy can occur independent of phylogeny. Comment: Line 30. This is plural, those are evidence to each effect. Response: Thank you for your comment. The word ‘these’ used in the original manuscript is plural and correct in this context and thus we have decided to keep it. Comment: Lines 32-35. This sentence is so complex, that it has a justification and objective, this became too confusing for an abstract. I suggest restructuring in two sentences. Response: Thank you for your comment. The requested change has been made. Comment: Lines 37-41. I suggest restructuring this sentence because it sounds contradictory to the objective in the abstract. Also, it sounds a little catastrophic when you said We fail! I recommend this…. Results showed that both genetic monogamy and polyandry have evolved multiple times independently….and in biological conditions. Response: Thank you for your comment. The requested change has been made. Comment: Lines 39-41 and 42-43. I think that this idea has been discussed in some articles. Karl in 2008 debated this idea and he demonstrated that monogamy is not always a maladaptive strategy. For its part, Lotterhos 2011 also refuted this idea with a model, which showed that any adverse effect derived from polyandry is attenuated by long generation times. Kvarnemo's 2018 observations about monogamy suggest that this cannot be a maladaptive strategy since it is present in many groups, even if its benefits are not in sight. Response: Thank you for your comment. We have added additional text in lines 81-86 and cited the requested references. Comment: Line 56. “rampant polyandry” how can I interpret it? Response: Thank you for your response. We have replaced the word rampant with widespread. Comment: Line 62. Add in parentheses, revised in 10. Because it is a single cite of information in this sentence and it is controversial. Response: Thank you for your comment. The requested change has been made. Comment: Line 65. I have a conflict with these cites (10-11). Although one of them is proposed for the animal kingdom, in general, it is necessary to think about the peculiarities of the elasmobranch group. My main conflict is in the citation of Simmons 2001 since he bases his arguments on insects. Please, you need to consider this for vertebrates and, particularly in elasmobranchs. Response: Thank you for your comment. For the purpose of this sentence, we do not see that any specific reference to elasmobranchs is required. Our understanding of the net fitness consequences of polyandry are poor across the animal kingdom, and the specific sentence you query was not talking only about elasmobranchs, but about our understanding of polyandry across animal life. The studies we cite are some of the only empirical tests of hypotheses concerning net fitness consequences, so when making a general statement such as “understanding of the net fitness consequences of polyandry are poor across the animal kingdom” they provide ideal references. We do go on to discuss later specific knowledge regarding elasmobranchs, but we do not believe that there is any issue with including these studies given the general nature of the statement. Comment: Line 85. What do you mean by “unwanted mating attempts”? Response: Thank you for your comment. We have clarified this in the text by replacing unwanted mating attempts with coercive mating Comment: Lines 91-94. You need to cite this sentence. Response: Thank you for your comment. We have made the change as requested. Comment: Lines 101-103. This sentence reflects that there are many mating systems and not just polyandry and monogamy, what would those be? The authors assume that readers understand the limitations of mating system studies in elasmobranchs, it seems to me not necessarily. By this, I mean that polygyny is very feasible in this group, although it is extremely difficult to verify. Response: Thank you for your comment. We have included additional text in lines 129-130 to clarify for the reader. We also provide additional text mentioning polygyny in lines 348-349 Comment: Lines 120-121. I agree that there is no best form to get a value of MP frequency for a species, however, it cannot reflect the actual mating system in species that have geographical variations, or seasonal variation. Also, the sample size is an important factor influencing the MP frequency in different studies for the same species, along with the resolution power offered by the different molecular tools employed. I suggest adding this in the limitations section, or better, stating those understandable limitations right after the methods. Response: Thank you for your comment. We have addressed this issue in the methodology in lines 149-158. Comment: Lines 123-125. Assuming this, authors need to discuss it in species with geographical variation in the MP. Response: Thank you for your comment. We have added extra text to acknowledge this limitation and justify our approach in the methodology, in lines 149-158 Comment: Lines 131-133. I invite to authors to read the articles before mentioned. I consider that it is not reflected in the introduction. Response: Thank you for your comment. As mentioned in our response to your previous comment we have read the articles and added text to the introduction as requested. Comment: Table 2. This table is unnecessary. I suggest sending it to supplementary materials and citing it in this part. Response: Thank you for your comment. We have decided to keep this table as it reports an important result that is referenced throughout the discussion. Comment: Lines 187-189. I’m not familiar with the analysis, however, looking at the tree, I think the analyses give a lot of weight to the MP value. I’m concerned that in some cases, such as M. californicus, the sample size is too low to consider real genetic monogamy, since a particularity of this work is possibly collecting small females with a low probability of observing MP. In this case, It can be an effect of the sample size. Response: Thank you for your comment. This is true to some extent, however the issues affecting this analyses are the same as those affecting the other analyses, and thus have been addressed in the limitations section. Even excluding cases with very low sample size there are still multiple cases in which very low values of MP have evolved, and even in species with low sample size it is unlikely that additional studies would find values dramatically different from existing studies. That is the main benefit of using a continuous measure of MP as opposed to a binary variable, as it allows use of MP as an approximation rather than a discrete variable that must show either monogamy or polyandry. We have added additional text in lines 149-158 to explain this. Comment: Lines 206-209. These ideas should be expressed in the abstract and of course in the introduction. Response: Thank you for your comment. This idea is already mentioned in lines 30-32 of the original abstract. We have added additional text in lines 75-79 in the introduction to further expand. Comment: Lines 220-222. I’m not sure if this is correct according to the abstract of Dibattista et al. 2008. In this abstract, they said…” We find that offspring from polyandrous litters did not have a greater genetic diversity or greater survival than did the offspring of monandrous litters”. This sentence is contrary evidence. Response: Thank you for your comment. DiBattista et al. 2008 do not present any data regarding monogamy, so their findings are not relevant to the sentence. However in the main text they do state that monogamy in sharks may reduce genetic variation, and hence this is why we included the reference. Comment: Lines 225-228. This idea is correct and is the best of all paper. This idea has been discussed. I suggest to the authors redirect the justification of their article considering their methodology. Response: Thank you for your comment. We believe that framing the paper in terms of the empirical results is the most scientifically robust choice. If you disagree with this we would welcome additional explanation of how you would alter the article’s focus or justification. Comment: Lines 239-241. Using the average MP in a species cannot reflect the real mating system. Response: Thank you for your comment. We believe that when comparing across species the approximation of average MP is the best available measure, as explained in the new text additions to the methodology. However as described in our response to a previous comment we have added text to the methodology to acknowledge this limitation. Comment: Lines 246-248. Please, read to Stephens & Sutherland 2000, they had already discussed it and explained the Allee effect in this context. Response: Thank you for your comment. We have read and cited the reference as requested. Comment: Lines 248-251. I do not agree. Since the model was not significant, I think the recurrent MP is not necessarily one adaptive peak. In this sense, this sentence is contradictory to the last sentence. Also, we need to consider that there are few studies to evaluate the mating system in the Elasmobranchii clade, thus this apparently adaptive peak can be skewed due to limited publications. Response: Thank you for your comment. We believe you may have been looking at the wrong table. Table 2 shows the results of our evolutionary model test. These tests do not come with p values and hence do not have a strict ‘significance’. They are compared on the basis of AIC, where a difference of 2 or more is considered significant. The Ornstein-Uhlenbeck model received substantially more support than the null model of Brownian motion. Therefore our results suggest that MP in elasmobranchs follows an OU model of trait evolution, in which there are one or more adaptive peaks. Of course the paucity of data does affect this analysis like all of the other analyses, and the limitations section was included specifically to address this. Comment: Lines 264-266. Excellent! Authors need to moderate some previous sentences according to this section. Response: Thank you for your comment. See our response to other comments for details of how we have made the requested changes. Comment: Lines 282-283. I think this is not demonstrated with your results. Response: Please see the above comment regarding Table 2. We found substantial support for an OU model of trait evolution over the null model of Brownian motion, which implies that MP is evolving towards one or more adaptive peaks. Reviewer 2 Comment: The potential link between multiple paternity, sexual selection and population viability is an important and general one, and I agree with the authors that this taxonomic group is a potentially useful model system in which to study it. That being said, I found it a little difficult to know what to conclude from this study. In principle I think it is important that negative findings are published, but I do have concerns as to whether the study really had sufficient power to test the hypothesis in question. To be fair to the authors, they are quite open about the limitations of the dataset in their discussion, so on balance I think I would be in favour, but first would like to see several more minor points addressed: Response: Thank you for your comment. We agree with the sentiment you convey. Of course the necessary data to robustly prove the fitness consequences and population level consequences of mate system variation in elasmobranchs do not yet exist. However, we believe this study is valuable as it not only provides valuable insight into the evolution of mating system variation in elasmobranchs, but may serve as the impetus for future studies that build on the existing data. We have endeavoured to make the requested changes wherever possible and hope that the revised manuscript addresses the concerns raised below. Comment: Line 117: The data are presented as coming form the existing literature, but ca. 80% come from a single source. For that reason, I think it would be appropriate to present already in the Introduction the potential overlaps and novel aspects relative to this previous study. Response: Thank you for your comment. The cited paper did itself gather these values from existing literature. The novelty of our study relative to Lamarca et al is discussed in lines 92-97. Essentially, their analyses is very simplistic, and doesn’t at all address potential population-level consequences. Rather it is entirely focussed on addressing the ancestral state of genetic mating system in elasmobranchs, however their analyses is very basic in this regard compared to our ancestral state reconstruction (Figure 3). Comment: 143: It’s unclear to me why conservation status was coded quantitatively, rather than adopt a different analysis approach for this variable? Linear regression doesn’t feel like the most appropriate approach here. Response: Thank you for your comment. After reviewing the approach we used, we have modified the text slightly in the methodology to explain better. The models we fit were phylogenetic generalised least squares regression models, which is a form of linear regression that takes into account phylogenetic non-independence. These models can incorporate discrete and continuous variables, and therefore using conservation status is entirely valid. We removed the text referencing coding as this has no effect on the results. Comment: 173-177: Given all of these “relationships” are non-significant, I don’t think it is very meaningful to discuss which slopes are positive and which are negative; all you can reliably conclude is that none could be distinguished from zero. Response: Thank you for your comment. We have now deleted this portion of the text. Comment: 200: on the face of it, purging would tend to reduce genetic diversity rather than increasing it - maybe take a bit more space to explain this point? Response: Thank you for your comment. Indeed the references to purging and genetic variation were supposed to be separate, and as such we have altered the sentence order to explain that these are Attachments Attachment Submitted filename: Response to reviewers.docx https://doi.org/10.1371/journal.pone.0308141.r002
3 Jul 2024 Decision Letter - Stefan Schlatt, Editor PONE-D-24-08235R1No evidence for population-level benefits of polyandry in sharks and raysPLOS ONE Dear Dr. Gayford, Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process. The revision of this paper has been a long journey. At this point the manuscript is almost appropriately revised and will not go back into re-review. However the reviewer mentions a few minor changes which I like to ask the authors to consider and implement. The paper will then be acceptable. Please submit your revised manuscript by Aug 17 2024 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. 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If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice. [Note: HTML markup is below. Please do not edit.] Reviewers' comments: Reviewer's Responses to Questions Comments to the Author 1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation. Reviewer #1: (No Response) ******** 2. Is the manuscript technically sound, and do the data support the conclusions? The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented. Reviewer #1: Partly ****** 3. Has the statistical analysis been performed appropriately and rigorously? Reviewer #1: Yes ****** 4. Have the authors made all data underlying the findings in their manuscript fully available? The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified. Reviewer #1: Yes ****** 5. Is the manuscript presented in an intelligible fashion and written in standard English? PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here. Reviewer #1: Yes ****** 6. Review Comments to the Author Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters) Reviewer #1: I consider that the authors aboarded all my comments and questions, especially in the interpretation of results. I agree with almost all editions that they made in the manuscript. However, I have some comments that I would like to see in the paper. In this sense, I suggest another round of revision. Abstract Lines 27-28. Please specify if this idea is for the elasmobranch clade or animal kingdom. Lines 37-40. I feel that the authors handle this idea a lot, but the topic is not delved into in the discussion, they leave everything to the reader's imagination. In this sense, I have a comment on the discussion. Lines 43-44. I insist that this idea is no longer under discussion currently, even in elasmobranchs. Also, it doesn't delve into it, I suggest eliminating it. Discussion Lines 239-242. I suggest exploring this idea a little further in the discussion, I can imagine what they are referring to, but I think it would be better to read it. Since the article is titled "No evidence for population-level benefits of polyandry in sharks and rays" I hope to see some examples in this regard to understand much better how the cancellation of both characteristics (benefits and costs) of the mating system does not necessarily impact the risk of extinction of a species. ****** 7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files. If you choose “no”, your identity will remain anonymous but your review may still be made public. Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy. Reviewer #1: No ******** [NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.] While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step. https://doi.org/10.1371/journal.pone.0308141.r003
Revision 2
4 Jul 2024 Author Response Response to reviewers: No evidence for population-level benefits of polyandry in sharks and rays We thank the editor and reviewer for their time spent on this manuscript. We are very grateful for both of your comments, and believe that they have greatly improved the quality of the paper. Please find detailed responses to comments below. We hope that you find the changes made sufficient to consider acceptance of the manuscript, as we have to the best of our abilities incorporated all changes suggested by the reviewer into the text. Reviewer 1 Comment: Lines 27-28. Please specify if this idea is for the elasmobranch clade or animal kingdom. Response: The sentence has been clarified as requested. Comment: Lines 37-40. I feel that the authors handle this idea a lot, but the topic is not delved into in the discussion, they leave everything to the reader's imagination. In this sense, I have a comment on the discussion. Response: Please see our response to the comment about the discussion. Comment: Lines 43-44. I insist that this idea is no longer under discussion currently, even in elasmobranchs. Also, it doesn't delve into it, I suggest eliminating it. Response: The statement has been eliminated as requested. Comment: Lines 239-242. I suggest exploring this idea a little further in the discussion, I can imagine what they are referring to, but I think it would be better to read it. Since the article is titled "No evidence for population-level benefits of polyandry in sharks and rays" I hope to see some examples in this regard to understand much better how the cancellation of both characteristics (benefits and costs) of the mating system does not necessarily impact the risk of extinction of a species. Response: The current version of the manuscript contains quite a lot of discussion of the costs and benefits of different mating systems. See lines 62-80 and lines 243-255. The fact is that all of these costs and benefits are highly context dependent (as we point out at several points in the text), so we cannot make detailed inferences about specific costs and benefits in specific shark or ray species as we lack the necessary contextual information. The current sections on costs and benefits address to the fullest extent possible how each of these factors could apply to sharks and rays, and provide references that delve deeper into the theoretical basis of those costs and benefits, should the reader be interested. Attachments Attachment Submitted filename: Response to reviewers_2.docx https://doi.org/10.1371/journal.pone.0308141.r004
9 Jul 2024 Decision Letter - Stefan Schlatt, Editor PONE-D-24-08235R2No evidence for population-level benefits of polyandry in sharks and raysPLOS ONE Dear Dr. Gayford, Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process. I am happy to see that the paper has been appropriately revised. One reviewer expresses minor concerns which I like to see addressed before the paper can be accepted for publication. Please submit your revised manuscript by Aug 23 2024 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file. Please include the following items when submitting your revised manuscript: A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'. A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'. An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'. If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter. If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: https://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols. Additionally, PLOS ONE offers an option for publishing peer-reviewed Lab Protocol articles, which describe protocols hosted on protocols.io. Read more information on sharing protocols at https://plos.org/protocols?utm_medium=editorial-email&utm_source=authorletters&utm_campaign=protocols. We look forward to receiving your revised manuscript. Kind regards, Stefan Schlatt Academic Editor PLOS ONE Journal Requirements: Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice. [Note: HTML markup is below. Please do not edit.] [NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.] While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step. https://doi.org/10.1371/journal.pone.0308141.r005
Revision 3
9 Jul 2024 Author Response The reference list has been checked, and is fully complete. No additional references need to be removed or added to the list. We have made some minor formatting adjustments for consistency as can be seen in the tracked changes document. Attachments Attachment Submitted filename: Response to reviewers_3.docx https://doi.org/10.1371/journal.pone.0308141.r006
18 Jul 2024 Decision Letter - Stefan Schlatt, Editor No evidence for population-level benefits of polyandry in sharks and rays PONE-D-24-08235R3 Dear Dr. Gayford, We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements. Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication. An invoice will be generated when your article is formally accepted. Please note, if your institution has a publishing partnership with PLOS and your article meets the relevant criteria, all or part of your publication costs will be covered. Please make sure your user information is up-to-date by logging into Editorial Manager at Editorial Manager® and clicking the ‘Update My Information' link at the top of the page. If you have any questions relating to publication charges, please contact our Author Billing department directly at authorbilling@plos.org. If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org. Kind regards, Stefan Schlatt Academic Editor PLOS ONE Additional Editor Comments (optional): Reviewers' comments: https://doi.org/10.1371/journal.pone.0308141.r007
Formally Accepted
19 Jul 2024 Acceptance Letter - Stefan Schlatt, Editor PONE-D-24-08235R3 PLOS ONE Dear Dr. Gayford, I'm pleased to inform you that your manuscript has been deemed suitable for publication in PLOS ONE. Congratulations! Your manuscript is now being handed over to our production team. At this stage, our production department will prepare your paper for publication. This includes ensuring the following: * All references, tables, and figures are properly cited * All relevant supporting information is included in the manuscript submission, * There are no issues that prevent the paper from being properly typeset If revisions are needed, the production department will contact you directly to resolve them. If no revisions are needed, you will receive an email when the publication date has been set. At this time, we do not offer pre-publication proofs to authors during production of the accepted work. Please keep in mind that we are working through a large volume of accepted articles, so please give us a few weeks to review your paper and let you know the next and final steps. Lastly, if your institution or institutions have a press office, please let them know about your upcoming paper now to help maximize its impact. If they'll be preparing press materials, please inform our press team within the next 48 hours. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org. If we can help with anything else, please email us at customercare@plos.org. Thank you for submitting your work to PLOS ONE and supporting open access. Kind regards, PLOS ONE Editorial Office Staff on behalf of Dr. Stefan Schlatt Academic Editor PLOS ONE https://doi.org/10.1371/journal.pone.0308141.r008

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