Medaka (Oryzias latipes) initiate courtship and spawning late at night: Insights from field observations

Yuki Kondo; Kotori Okamoto; Yuto Kitamukai; Yasunori Koya; Satoshi Awata

doi:10.1371/journal.pone.0318358

Peer Review History

Original SubmissionOctober 27, 2024
26 Dec 2024 Decision Letter - Nicholas S. Foulkes, Editor PONE-D-24-48646Medaka (Oryzias latipes) initiate courtship and spawning late at night: Insights from field observationsPLOS ONE Dear Dr. Kondo, 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. This manuscript has been well received by both reviewers and there are only relatively minor adjustments that are needed for the text. Please submit your revised manuscript by Feb 09 2025 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If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice.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. 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: Yes Reviewer #2: Yes ******** 2. Has the statistical analysis been performed appropriately and rigorously? Reviewer #1: Yes Reviewer #2: Yes ****** 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: This is a nice field study that provides novel information on the mating behaviour of a species commonly used as laboratory model. I provided below a list of suggestions that may improve the presentation of the study and in a few cases the credibility of the conclusions. Suggestions L27 Would not be clearer if welfare improvement was mentioned around here? Maybe also mention that the results of various types of research can be flawed by lack of welfare/presence of stress, such as for behavioural studies. L46-47 This sentence seems to be redundant with lines 38-39. I suggest to remove it, also considering that the paragraph focus on laboratory settings. L50 Looking for mates is a possible explanation but it is not suggested based on what written. L65 Please specify what is this clade categorisation for readers who do not work with medaka. L85 It is important to exclude that the red light did not trigger mating. The light could have been perceived as the beginning of sunrise by the nearby fish. From the results, I would say that mating occurred after the appearance of the light. Maybe add this conclusion in your discussion if you think it is correct. L93 I understand that the presence of eggs was taken as evidence that spawning has just occurred. For this to be true, we need data demonstrating that the eggs are always dropped soon after spawning. Is there any supporting study to be cited in the literature? L170 The temporal trend of the mating behaviours is similar to that of appearance. Can you compute a variable that excludes that the increase in mating behaviours was just the consequence of more fish appearing? I am thinking to something like a ratio between the number of fish observed and the number of these fish conducting mating behaviours. Reviewer #2: The manuscript "Medaka (Oryzias latipes) initiate courtship and spawning late at night: Insights from field observations”by Kondo et al. reports on the temporal mating behaviour of wild medaka in their native habitat. This interesting filed work documents mating behaviour of a wild medaka group using simple and therefore reliable video observation. The results reveal a significant difference of mating time from wild medaka to those under laboratory conditions. It thus provides important information on basic biological attributes of this widely used vertebrate genetic model and underscores the necessity of field work to better know/understand our laboratory animal models. The filed work is well documented using a simple observation methodology with a adequate analysis of the data. The manuscript is well written, but there are a few errors/weak phrasings in the abstract that should be addressed prior to publication. minor points: line 3: To complement laboratory experiments….rather than: to better inform… line 6 delete “show" line 8 change to: revealed the presence of post-spawning females….or an adequate phrasing ****** 6. 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 Reviewer #2: 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.0318358.r001
Revision 1
3 Jan 2025 Author Response Reviewer #1 Comments and Responses This is a nice field study that provides novel information on the mating behaviour of a species commonly used as laboratory model. I provided below a list of suggestions that may improve the presentation of the study and in a few cases the credibility of the conclusions. REPLY: We sincerely thank the reviewer #1 for his/her thorough review and positive assessment of our field study on medaka mating behavior. The reviewer’s constructive suggestions have helped improve both clarity and scientific rigor of our manuscript. We have carefully addressed all points to enhance the presentation and strengthen our conclusions. Specific responses to each comment are detailed below. Suggestions L27 Would not be clearer if welfare improvement was mentioned around here? Maybe also mention that the results of various types of research can be flawed by lack of welfare/presence of stress, such as for behavioural studies. REPLY: We have added a sentence to explicitly mention how stress or lack of welfare can impact research outcomes. See lines 34-37. L46-47 This sentence seems to be redundant with lines 38-39. I suggest to remove it, also considering that the paragraph focus on laboratory settings. REPLY: The suggested sentence has been removed to streamline the paragraph and maintain focus on laboratory settings. See line 56. L50 Looking for mates is a possible explanation but it is not suggested based on what written. REPLY: We have revised the text to make the statement about searching for mates more tentative and evidence-based. See lines 58-59. L65 Please specify what is this clade categorisation for readers who do not work with medaka. REPLY: We have added clarifying text about medaka clades. See lines 74-76. L85 It is important to exclude that the red light did not trigger mating. The light could have been perceived as the beginning of sunrise by the nearby fish. From the results, I would say that mating occurred after the appearance of the light. Maybe add this conclusion in your discussion if you think it is correct. REPLY: We have addressed concerns about the red light effects by: 1. Adding references to prior research showing no effects on reproductive behavior. See lines 93-95. 2. Revising the flow of discussion on light effects. See lines 243-257. L93 I understand that the presence of eggs was taken as evidence that spawning has just occurred. For this to be true, we need data demonstrating that the eggs are always dropped soon after spawning. Is there any supporting study to be cited in the literature? REPLY: We are sorry for insufficient information of medaka spawning. Different from many other fishes, medaka females temporarily carry the spawned eggs hanging from their abdomen. Within a few hours, they attach all these eggs to aquatic plants or similar substrates. We have added these information with supporting citations. See lines 103-109. L170 The temporal trend of the mating behaviours is similar to that of appearance. Can you compute a variable that excludes that the increase in mating behaviours was just the consequence of more fish appearing? I am thinking to something like a ratio between the number of fish observed and the number of these fish conducting mating behaviours. REPLY: In response to the comment, we created figure showing the proportion of each behavior observed during different time periods (see below). The results showed no clear variation in the proportion of individual swimming across time periods. However, the proportion of Stay decreased from 21:00 to 1:00, while the proportions of courtship behaviors such as Following and Quick Circle increased. This indicates that the increase in courtship behavior frequency was not merely due to the increased appearance of medaka during late-night to early-morning hours but rather reflects an actual increase in courtship behavior. As these findings are suggested in the current Fig. 1 and Fig. 2, we decided not to include the new figure in the manuscript. See Figures. Reviewer #2 Comments and Responses The manuscript "Medaka (Oryzias latipes) initiate courtship and spawning late at night: Insights from field observations” by Kondo et al. reports on the temporal mating behaviour of wild medaka in their native habitat. This interesting filed work documents mating behaviour of a wild medaka group using simple and therefore reliable video observation. The results reveal a significant difference of mating time from wild medaka to those under laboratory conditions. It thus provides important information on basic biological attributes of this widely used vertebrate genetic model and underscores the necessity of field work to better know/understand our laboratory animal models. The filed work is well documented using a simple observation methodology with a adequate analysis of the data. The manuscript is well written, but there are a few errors/weak phrasings in the abstract that should be addressed prior to publication. REPLY: We greatly appreciate the reviewer #2 for his/her positive evaluation of our field study. We are particularly encouraged by the recognition of how our findings contribute to understanding basic biological attributes of this important model organism and highlight the value of field observations. As suggested, we have carefully revised the abstract to address the identified phrasing issues. minor points: line 3: To complement laboratory experiments….rather than: to better inform… REPLY: Revised to “To complement laboratory experiments” as suggested. See line 13. line 6 delete “show” REPLY: Deleted “show” for conciseness. See line 15. line 8 change to: revealed the presence of post-spawning females….or an adequate phrasing REPLY: Revised to “revealed the presence of post-spawning females” for clarity. See line 18. https://doi.org/10.1371/journal.pone.0318358.r002
15 Jan 2025 Decision Letter - Nicholas S. Foulkes, Editor Medaka (Oryzias latipes) initiate courtship and spawning late at night: Insights from field observations PONE-D-24-48646R1 Dear Dr. Kondo, 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, Nicholas S. Foulkes, D.Phil Academic Editor PLOS ONE Additional Editor Comments (optional): Reviewers' comments: https://doi.org/10.1371/journal.pone.0318358.r003
Formally Accepted
17 Jan 2025 Acceptance Letter - Nicholas S. Foulkes, Editor PONE-D-24-48646R1 PLOS ONE Dear Dr. Kondo, 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. Nicholas S. Foulkes Academic Editor PLOS ONE https://doi.org/10.1371/journal.pone.0318358.r004

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