A Systematic Review of the Relationship Between Host Personality Traits and Parasitic Infection

Round 1

Reviewer 1 Report (Previous Reviewer 1)

Comments and Suggestions for Authors

The authors have addressed the main shortcomings I identified in my previous review. The article is recommended for publication.

Author Response

Comments 1: The authors have addressed the main shortcomings I identified in my previous review. The article is recommended for publication.

Response 1:  Thank you very much.

 

Reviewer 2 Report (Previous Reviewer 2)

Comments and Suggestions for Authors

This is a resubmitted manuscript. I had supported the original submission but obviously the editor felt differently.

Anyway, the authors have made an effort and there is significant improvement in the manuscript. Unfortunately, however, some flaws have crept in the resubmitted manuscript that need to be corrected.

 

For example, the PRISMA diagram has not been done properly. This is a major issue, because really this helps to understand the flow of the paper admission or rejection. Please go into the webpage of the PRISMA and download the template available there and please follow that very closely and redo the flow.

 

Table 1. Please list the host alphabetically.

Unfortunately, this manuscript suffers from the very poor visualization. Really, numbers of table and figures must be improved. I expect at least 5 tables and 8 graphs in the revised manuscript.

The appendices should be moved to supplementary material.

In Results, can you please describe if there are any associations with the year of publication of the papers evaluated? This will help to understand temporal changes in the orientation of the relevant papers.

 

Finally, conclusions. This section is a bit on the long side, hence please delete one or two sentences and it will become very ok.

 

Overall. Extensive changes are needed. The resubmitted manuscript will required further close evaluation.

 

Recommendation. Major revision and re-assessment.

Author Response

Comments 1: This is a resubmitted manuscript. I had supported the original submission but obviously the editor felt differently. Anyway, the authors have made an effort and there is significant improvement in the manuscript. Unfortunately, however, some flaws have crept in the resubmitted manuscript that need to be corrected.

Response 1: Thank you very much for your comments. We have made corresponding revisions based on the opinions you provided.

Comments 2: For example, the PRISMA diagram has not been done properly. This is a major issue, because really this helps to understand the flow of the paper admission or rejection. Please go into the webpage of the PRISMA and download the template available there and please follow that very closely and redo the flow.

Response 2: Thank you very much for your comments. We have downloaded the relevant template from the PRISMA website and revised the manuscript according to the comments provided[Lines 115-116].

Comments 3: Table 1. Please list the host alphabetically.

Response 3: Thank you very much for your suggestion. We have presented the table in the form of two figures to illustrate its content more clearly[Lines 125-128].

Comments 4: Unfortunately, this manuscript suffers from the very poor visualization. Really, numbers of table and figures must be improved. I expect at least 5 tables and 8 graphs in the revised manuscript.

Response 4: Thank you very much for your suggestion. We have added three figures to improve the visualization of the manuscript[Lines 125-128, Lines 137-138].

Comments 5: The appendices should be moved to supplementary material.

Response 5: Thank you for your kind suggestion. We have placed the appendices in the supplementary material.

Comments 6: In Results, can you please describe if there are any associations with the year of publication of the papers evaluated? This will help to understand temporal changes in the orientation of the relevant papers.

Response 6: Thank you very much for your suggestion. We have described the correlation between publication years in the Results section and created a figure to illustrate this more clearly[Lines 131-134, Lines 137-138].

Comments 7: Finally, conclusions. This section is a bit on the long side, hence please delete one or two sentences and it will become very ok.

Response 7: Thank you very much for your suggestion. We have removed some sentences from the conclusion to streamline it.

Comments 8: Overall. Extensive changes are needed. The resubmitted manuscript will required further close evaluation.

Response 8: Thank you very much for your valuable suggestions and feedback. They have been extremely helpful in guiding my revisions.

Comments 9: Recommendation. Major revision and re-assessment.

Response 9: Thank you very much for your constructive suggestion. We have revised the manuscript accordingly.

Reviewer 3 Report (Previous Reviewer 3)

Comments and Suggestions for Authors

The paper is improved in terms of legibility. The authors has answered to my queries and the paper is now ok for me.

Author Response

Comments 1: The paper is improved in terms of legibility. The authors has answered to my queries and the paper is now ok for me.

Response 1: Thank you very much.

Round 2

Reviewer 2 Report (Previous Reviewer 2)

Comments and Suggestions for Authors

No further comments.

This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The authors wanted to study the complex symbiotic relationships between various species of living organisms (insects, arachnids, mollusks, fish, amphibians, reptiles, birds, mammals, and others – lines 105–107) and their symbionts (understanding this term in a narrower sense, a particular case of symbiosis – parasitism). Surprisingly, the authors of this literature review limited themselves to 45 articles to analyze this complex ecological, veterinary, and medical problem. Such a superficial analysis could not lead to serious scientific generalizations.

The main problem with this analysis is the very narrow selection of keywords: the authors limited themselves to the words “personality,” “behavioral syndrome,” “parasite,” and “parasitism.” Had the authors conducted a more in-depth analysis of the problem for each group of parasites (lines 109–111) to find the necessary information, the results of their analysis would have been different. Conclusions based on such a small number of articles cannot be taken seriously unless the search was focused on the Latin name of the parasite species.

I recommend the authors conduct a more in-depth analysis of the literature, for example, on one of the common trematode species, or hundreds of articles on ixodid and gamasid ticks. Articles on the effects of nematodes on their hosts constitute a separate, extensive cluster of scientific publications. Sporozoa have been studied in great detail in this regard. For example, gregarines exhibit a wide range of effects on host insects depending on habitat pollution, temperature, water salinity, and the presence of other parasites. These are highly complex and dynamic interactions. The authors' conclusions are very superficial: they will be significantly refined with a more in-depth study of individual parasite groups.

The authors misunderstand the factors that may influence the results of their study. Under certain conditions of interaction between the parasite and host populations, the former will significantly suppress the host organism, while under others, the hosts may even derive certain benefits from the presence of parasites. This will lead to a unification of the concepts of parasitism, mutualism, commensalism, and other types of ecological relationships.

The scale of the problem being studied is so vast that it cannot even be briefly described in 15 pages of an article. There are anywhere from several hundred thousand to several million species of parasites on Earth. It is likely that between one-third and two-thirds of all living organisms on Earth are parasites. Even for a single family or order of helminths (a group of nematodes, trematodes, or cestodes), the authors' conclusions will change significantly if they wish to delve deeper into the specific scientific literature.

I do not recommend this article for publication due to its flawed approach. To search for information, the authors enter the words "parasite" and "parasitism" into Web of Science, which inherently implies a specific type of negative impact of one species on another. This is unacceptable.

A more accurate search for information would be to use a broader set of phrases—synonyms for the words "personality" and "behavioral syndrome" (5-7 phrases), as well as the Latin names of individual parasite species (not orders, classes, or phyla). Then, the results will be more or less complete.

The authors selected one of the central problems in parasitology and described it very superficially. The results of such an analysis cannot be considered satisfactory. I regret, but this manuscript cannot be published due to a significant methodological error and very limited search criteria.

Author Response

Response to Reviewer 1

Comments 1:  The authors wanted to study the complex symbiotic relationships between various species of living organisms (insects, arachnids, mollusks, fish, amphibians, reptiles, birds, mammals, and others – lines 105–107) and their symbionts (understanding this term in a narrower sense, a particular case of symbiosis – parasitism). Surprisingly, the authors of this literature review limited themselves to 45 articles to analyze this complex ecological, veterinary, and medical problem. Such a superficial analysis could not lead to serious scientific generalizations.

Response 1:  Thank you very much for your suggestions. We conducted another literature research based on your suggestions, resulting in more relevant papers included in our analysis.

Comments 2:  The main problem with this analysis is the very narrow selection of keywords: the authors limited themselves to the words “personality,” “behavioral syndrome,” “parasite,” and “parasitism.” Had the authors conducted a more in-depth analysis of the problem for each group of parasites (lines 109–111) to find the necessary information, the results of their analysis would have been different. Conclusions based on such a small number of articles cannot be taken seriously unless the search was focused on the Latin name of the parasite species.

Response 2: We are grateful to this highly constructive comment. Regarding your suggestions, we have expanded and adjusted the search terms to increase the usage of literature [Lines 118-122].

Comments 3:  I recommend the authors conduct a more in-depth analysis of the literature, for example, on one of the common trematode species, or hundreds of articles on ixodid and gamasid ticks. Articles on the effects of nematodes on their hosts constitute a separate, extensive cluster of scientific publications. Sporozoa have been studied in great detail in this regard. For example, gregarines exhibit a wide range of effects on host insects depending on habitat pollution, temperature, water salinity, and the presence of other parasites. These are highly complex and dynamic interactions. The authors' conclusions are very superficial: they will be significantly refined with a more in-depth study of individual parasite groups.

Response 3:  Thank you for your suggestions. We agree that there are a large number of papers on parasites. However, the major aim of this paper is to review the studies on the relationship between host personality and parasite infection, rather than general parasitology. According to our literature search, the number of papers focusing on this topic is relatively limited (but still enough for a systematic review). Based on our updated literature search (thanks again for your kind suggestions!), a wide range of host and parasite species have been included to achieve the purpose of systematic elaboration.

Comments 4:  The authors misunderstand the factors that may influence the results of their study. Under certain conditions of interaction between the parasite and host populations, the former will significantly suppress the host organism, while under others, the hosts may even derive certain benefits from the presence of parasites. This will lead to a unification of the concepts of parasitism, mutualism, commensalism, and other types of ecological relationships.

Response 4:  Thank you for pointing out this. We agree that there are many types of interspecific interactions and ecological relationships, and mutualism and commensalism are definitely interesting topics. In our study, however, we only focus on parasitism.

Comments 5:  The scale of the problem being studied is so vast that it cannot even be briefly described in 15 pages of an article. There are anywhere from several hundred thousand to several million species of parasites on Earth. It is likely that between one-third and two-thirds of all living organisms on Earth are parasites. Even for a single family or order of helminths (a group of nematodes, trematodes, or cestodes), the authors' conclusions will change significantly if they wish to delve deeper into the specific scientific literature.

Response 5:  We agree that parasites are highly diverse. However, relevant studies on relationship between host personality and parasitic infection are relatively limited in number. Moreover, the previous findings seem to be complex and no generic pattern exists. It is also interesting to explore whether there are research gaps and methodological issues in previous studies. In this scenario, we think it is both possible and timely to conduct such a review.

Comments 6:  I do not recommend this article for publication due to its flawed approach. To search for information, the authors enter the words "parasite" and "parasitism" into Web of Science, which inherently implies a specific type of negative impact of one species on another. This is unacceptable.

Response 6:  Thank you for your suggestion. We have adjusted the search terms, and in addition to retrieving results for the previous keywords, We have added keywords for each phylum of parasites to expand the search scope [Lines 106-110].

Comments 7:  A more accurate search for information would be to use a broader set of phrases—synonyms for the words "personality" and "behavioral syndrome" (5-7 phrases), as well as the Latin names of individual parasite species (not orders, classes, or phyla). Then, the results will be more or less complete.

Response 7:  Thank you for your suggestions. However, it is impossible to directly use Latin names of parasite species as keywords, since the number of parasite species is very large (as you mentioned above). As an alternative approach, we included the English names of several major parasite taxa (e.g. tick, flea, nematode, tapeworm) in our keywords. More papers were included and many parts of the review were then rewritten.

Comments 8: The authors selected one of the central problems in parasitology and described it very superficially. The results of such an analysis cannot be considered satisfactory. We regret, but this manuscript cannot be published due to a significant methodological error and very limited search criteria.

Response 8: Thanks for pointing out the drawbacks of our manuscript. We have substantially revised the paper according to your suggestions, and hopefully the revised manuscript is now more satisfactory.

Reviewer 2 Report

Comments and Suggestions for Authors

This is a useful and well-written manuscript that can be published with minimal changes. The authors have made a fantastic effort and they deserve to see their work published.

 

Some minor points are listed below in order to improve the final paper.

 

1. The justification for writing the paper is not strong, therefore please elaborate on this issue.
2. Please explain the gap that will filled by publishing this paper and also the help that will be provided to future workers.
3. Please explain why you preferred Web of Science over Scopus.
4. Figure 1, please add colours inside the boxes to make the reading easier.
5. 2.4., the first paragraph in a table please.
6. 2.5., this section can be extended, because really this is the heart of the entire paper.
7. Discussion, please add an introductory section as 3.1. with the first three paragraphs.
8. Please add an additional section in Discussion to present the effects of interactions in the development of antiparasitic drugs and vaccines.
9. Conclusions. Please shorten, some text can be transferred in Discussion.
10. Conclusions. Please close with a strong takeaway sentence.

 

 

Overall. Excellent manuscript for immediate acceptance after making the above changes.

 

 

Author Response

Response to Reviewer 2

 

Comments 1: This is a useful and well-written manuscript that can be published with minimal changes. The authors have made a fantastic effort and they deserve to see their work published. Some minor points are listed below in order to improve the final paper.

Response 1: Thank you very much for your comments. We have revised the manuscript in accordance with the comments provided. We hope our revision help to promote the quality of the paper.

Comments 2: The justification for writing the paper is not strong, therefore please elaborate on this issue.

Response 2: Thank you very much for your suggestion. We rewrote this part in our revised manuscript to highlight the importance of the review [Lines 87-102].

Comments 3: Please explain the gap that will filled by publishing this paper and also the help that will be provided to future workers.

Response 3: We included in the introduction how this paper helps current research and the insights and assistance it provides to future researchers [Lines 96-102].

Comments 4: Please explain why you preferred Web of Science over Scopus.

Response 4: We selected Web of Science because it employs a long-standing and relatively rigorous journal selection standard, which is manually reviewed by the editorial team. In addition, the citation indexing technology of Web of Science is more mature, allowing for more standardized integration of high-quality relevant papers.

Comments 5: Figure 1, please add colours inside the boxes to make the reading easier.

Response 5: We added appropriate colors in the box of Figure 1 to facilitate reading.

Comments 6: 2.4., the first paragraph in a table please.

Response 6: Thank you very much for your suggestion. We have added a table (Table 1) in the revised MS) in section 2.4 to better explain the first paragraph.

Comments7 : 2.5., this section can be extended, because really this is the heart of the entire paper.

Response 7: Thanks for your kind suggestion. In our revised MS, we enriched this part and moved it to Discussion (Sections 3.2 and 3.4 in the revised MS).

Comments 8: Discussion, please add an introductory section as 3.1. with the first three paragraphs.

Response 8:  Thank you. In the revised MS, we added a new section 3.1 as an overview of the previous studies [Lines 126-153].

Comments 9: Please add an additional section in Discussion to present the effects of interactions in the development of antiparasitic drugs and vaccines.

Response 9: Thanks for your suggestion. We added some contents on this topic at the end of Conclusion, because we feel it is more like a perspective [lines 288-290].

Comments 10: Conclusions. Please shorten, some text can be transferred in Discussion.

Response 10: We rewrote this part following your suggestion [Lines 279-290].

Comments 11: Conclusions. Please close with a strong takeaway sentence.

Response 11: Thank you very much for your suggestions. We have adjusted the conclusion to be more concise [Lines279-290].

Comments 12: Overall. Excellent manuscript for immediate acceptance after making the above changes.

Response 12: Thank you very much for your valuable suggestions and feedback. They have been extremely helpful in guiding my revisions.

Reviewer 3 Report

Comments and Suggestions for Authors

The paper intends to relate behaviour of hosts with intensity of infection with a parasite.  The idea is interesting. There are the following problems in this paper:

• Parasitism definition is wide and some include fungi, and others bacteria or viruses. It should be stated what was considered as parasite since 1 paper is based on fungi and one proteobacteria. Why then not include viruses? Or delete fungi and bacteria? The term “Pyrenomycetes” is no longer used in a taxonomic sense and has been replaced by the term; Sordariomycetes  It is one of three major class of fungi in the phylum Ascomycota. The proteobacteria are an important group of gram-negative bacteria.
• The term personality is rather used f or humans since there is a strong link to psychology Here is the definition of Encyclopaedia Britannica “personality, a characteristic way of thinking, feeling, and behaving. Personality embraces moods, attitudes, and opinions and is most clearly expressed in interactions with other people. It includes behavioral characteristics, both inherent and acquired, that distinguish one person from another and that can be observed in people’s relations to the environment and to the social group.” It was used in this paper as behaviour characterization. Personality should not be employed, use rather behaviour traits.
• The “personality “traits should be explained. How were measured boldness, activity etc This is absolutely needed. Was it obtained directly from the papers or interpreted by the authors of present paper.?
• I think these traits are not independent and not following a Gaussian distribution. Thus, correlation should be Spearman correlation (no information in the paper). A multiple regression could also be used after normalization of the data.
• It is not always clear if the behavioural trait is the cause or the result of infection. For example, protostrongylid nematodes infecting molluscs modify the geotropism of the snails. It is then the result of infection.
• The number of papers include 45 records but covers many different hosts and parasites. Thus, the parasite-hosts categories have limited numbers. It is probably why the authors did not comment on differences between parasites. It will be expected that parasites that multiply within hosts (increase as R0) and those that do not (fitness value) will not rely to the same extent on host behaviour. It would have been interesting to compare the results between those two categories of parasites.
•  The map is not needed since it brings only the location of studies.
• The differences between the three relationships (positive or negative significant correlation, and absence of correlation) are not important within each behaviour trait. It is like the three possibilities are equally possible. It seems driven by pure chance.

The discussion is much too long considering the obtained results.

Author Response

Response to Reviewer 3 Comments 1:  Parasitism definition is wide and some include fungi, and others bacteria or viruses. It should be stated what was considered as parasite since 1 paper is based on fungi and one proteobacteria. Why then not include viruses? Or delete fungi and bacteria? The term “Pyrenomycetes” is no longer used in a taxonomic sense and has been replaced by the term; Sordariomycetes  It is one of three major class of fungi in the phylum Ascomycota. The proteobacteria are an important group of gram-negative bacteria. Response 1: Agree. Thank you for your comments. In response, to avoid ambiguity, We have excluded from consideration those organisms that are somewhat controversial, such as fungi, bacteria, and viruses. Additionally, We have appropriately supplemented the discussion with some articles on research regarding personality traits and parasitic infections [Lines 126-132]. Comments 2:  The term personality is rather used for humans since there is a strong link to psychology Here is the definition of Encyclopaedia Britannica “personality, a characteristic way of thinking, feeling, and behaving. Personality embraces moods, attitudes, and opinions and is most clearly expressed in interactions with other people. It includes behavioral characteristics, both inherent and acquired, that distinguish one person from another and that can be observed in people’s relations to the environment and to the social group.” It was used in this paper as behaviour characterization. Personality should not be employed, use rather behaviour traits. Response 2:  Thank you for your suggestions. In behavioral ecology, personality refers to consistent behavioral difference among individuals. We agree the term here is more related to behavioral traits rather than a psychological term. However, it has been widely accepted and frequently used in behavioral ecology. Moreover, compared to behavioral traits, personality here emphasizes the consistency of a certain behavioral mode, which can even be heritable. We then decided to use the term ‘personality’ in our MS. We clarified this in the revised MS [Lines 65-80]. Comments 3:  The “personality “traits should be explained. How were measured boldness, activity etc This is absolutely needed. Was it obtained directly from the papers or interpreted by the authors of present paper.? Response 3:  Thanks for your suggestion. In the revised MS, we described methods for measuring personality traits in the introduction section [Lines 72-80]. Comments 4:  I think these traits are not independent and not following a Gaussian distribution. Thus, correlation should be Spearman correlation (no information in the paper). A multiple regression could also be used after normalization of the data. Response 4: Thanks for your comment. As a review, our study is fully based on the results generated by the original researches, so we did not actually conduct statistical analyses such as regressions. Comments 5:  It is not always clear if the behavioural trait is the cause or the result of infection. For example, protostrongylid nematodes infecting molluscs modify the geotropism of the snails. It is then the result of infection. Response 5:  Thank you for your highly valuable comment. You pointed out an important issue. Yes, the causality relationship between personality and infection is often difficult to verify, especially when most studies are by essence observational or correlational studies. In the revised MS, we added a new section (3.4) to discuss this issue and emphasize the values of BACI experiments, which is more powerful to verify the causal relationships. Comments 6:  The number of papers include 45 records but covers many different hosts and parasites. Thus, the parasite-hosts categories have limited numbers. It is probably why the authors did not comment on differences between parasites. It will be expected that parasites that multiply within hosts (increase as R0) and those that do not (fitness value) will not rely to the same extent on host behaviour. It would have been interesting to compare the results between those two categories of parasites. Response 6:  Thank you very much for your suggestion. At this stage, we are unable to conduct such analyses because we did not have enough case studies that simultaneously study these different parasite species with a single host species. However, we agree that parasite type may be an important factor to shape the relationship between host personality and parasitic infection. We clarified this in the revise MS and emphasized its importance [Lines 241-243]. Comments 7:  The map is not needed since it brings only the location of studies. Response 7: Thank you. We think this map is useful because geographic biases of previous studies can be easily viewed from this map. In the revised manuscript, we moved the map to Appendix, to make the article more concise. Comments 8:  The differences between the three relationships (positive or negative significant correlation, and absence of correlation) are not important within each behaviour trait. It is like the three possibilities are equally possible. It seems driven by pure chance. Response 8:  Thank you for your comment. In the revised MS, we rewrote this part substantially. Now the three different kinds of results are combined in one section, and we discussed the potential mechanism behind each pattern. However, we think it may not be merely random event. Other covariates (such as host sex, dimension of personality trait and even experimental design) may significantly shape the relationship between host personality and parasitic infection. We discussed this issue in sections 3.3 and 3.4. Comments 9: The discussion is much too long considering the obtained results. Response 9: Thanks a lot for your constructive comment. In the revised MS, we rewrote this part substantially and significantly shorten its length.