PONE-D-21-03679

Footprints to Singularity: A global population model explains late 20th century slow-down and predicts peak within ten years.

PLOS ONE

Dear Dr. Bystroff,

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 reviewers agreed on major revision; and the points raised in the reviewers' reports are centred on two major issues: Poor presentation of the data, model and analysis as stated by Reviewer 1; and that the literature is underrepresented and the contributions to the literature are not clearly explained as argued by Reviewer 2. We expect that you can address these issues in the revisions and your revised manuscript will be reconsidered accordingly.

Please submit your revised manuscript by 10 May 2021. 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.

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We look forward to receiving your revised manuscript.

Kind regards,

Eda Ustaoglu, PhD

Academic Editor

PLOS ONE

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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

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2. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: N/A

Reviewer #2: N/A

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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: No

Reviewer #2: Yes

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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: No

Reviewer #2: Yes

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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: I have given detailed comments on the paper in the attached pdf. But my overall comments are as follows.

The topic of the paper is of considerable interest.

But it is very poorly presented with material all over the place.

The mathematical model is poorly presented

The analysis of the parameter fitting is not at all clear.

The assumptions of the work are not clearly articulated.

The data that the model is based on is not clear.

I did not enjoy reading this paper as a mathematical modeller as the presentation was so disjointed.

The work needs a complete overhaul. If that is done successfully then it could well be suitable for publication. See my comments in the attached pdf.

The paper is very close to being rejected outright but the topic is a timely one. However, I do not want to see it again. I was very disappointed with the way the modelling was presented and the disjointed nature of the work..

Reviewer #2: This is a fairly standard variation of the 'world model' of the Club of Rome flavor and its may variants over the years.

The notion of 'knowledge and obsolescence' may be slightly novel, but if they are modeled as 'stocks' as they are here, this is no different than a standard economic growth model with investment and depreciation. The mathematical symbols have just been given different names.

The manuscript misses a very large literature on economic growth and the environment that uses coupled differential equation models (i.e. system dynamics) developed in mathematical bioeconomics. This is not surprising given the 'engineering-system dynamics' tradition from whence this model comes. These two literatures have often missed one another, creating useless discussions (i.e. the conflict/arguments between the Club of Rome lead by D. H. and D.L. Meadows and multiple economists who focus on economic growth such as Robert Solow, Geoffrey Heal, and Joseph Stiglitz in the 1970's and 80's) and multiple re-inventions of the wheel.

To be publishable, this manuscript must demonstrate what it adds to this literature. The trajectories shown in Figures 1-4 are very generic - you can find countless versions of these pictures in the literature. Fitting them to historical data is not difficult or particularly interesting. Thus, I suggest the authors carefully articulate what their model adds, taking into account the literature they missed, including

1) Brander, James A., and M. Scott Taylor. "The simple economics of Easter Island: A Ricardo-Malthus model of renewable resource use." American economic review (1998): 119-138.

There are many variations on this. It is essentially a 'world model'.

2) Anderies, John M. "Economic development, demographics, and renewable resources: a dynamical systems approach." Environment and Development Economics (2003): 219-246.

Again a world model. This one rigorously analyses the 'generic' behavior of all such models. You will see all the trajectories there that appear in this manuscript.

3) Beltratti, Andrea. "Growth with natural and environmental resources." New directions in the economic theory of the environment 25 (1997): 7.

4) Beltratti, Andrea. Models of economic growth with environmental assets. Vol. 8. Springer Science & Business Media, 1996.

5) Beltratti, Andrea, Geoffrey M. Heal, and Graciela Chichilnisky. "Sustainable growth and the green golden rule." Available at SSRN 1374662 (1995).

6) Chichilnisky, Graciela, Geoffrey Heal, and Andrea Beltratti. "The green golden rule." Economics Letters 49.2 (1995): 175-179.

7) Xepapadeas, Anastasios. "Economic growth and the environment." Handbook of environmental economics 3 (2005): 1219-1271.

and follow up on the many other models cited in those papers.

Until the model is correctly placed in the existing literature and its novel contribution clarified, it is just another variation of hundreds of such models.

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Reviewer #1: No

Reviewer #2: No

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Attachments

Attachment

Submitted filename: PONE-D-21-03679_reviewer-1.pdf

PONE-D-21-03679R1

Footprints to Singularity: A global population model explains late 20th century slow-down and predicts peak within ten years.

PLOS ONE

Dear Dr. Bystroff,

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.

Please add the postscript to the paper.

Please submit your revised manuscript by 28 May 2021. 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: http://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,

Eda Ustaoglu, PhD

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.

Additional Editor Comments (if provided):

Dear Dr Bystroff,

regarding your request to add a postscript in the paper, you can do this now.

I submit 'minor revision decision' to allow you adding the postscript.

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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 #2: All comments have been addressed

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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 #2: (No Response)

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3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #2: (No Response)

**********

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 #2: (No Response)

**********

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 #2: (No Response)

**********

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 #2: (No Response)

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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 #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.

Footprints to Singularity: A global population model explains late 20th century slow-down and predicts peak within ten years.

PONE-D-21-03679R2

Dear Dr. Bystroff,

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.

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Kind regards,

Eda Ustaoglu, PhD

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Reviewers' comments: