“Lepidoptera Flies”, but Not Always…Interactions of Caterpillars and Chrysalis with Soil

Round 1

Reviewer 1 Report

General comments

The MS gives us information about soil related Lepidoptera species and what is the evolutionary logic behind it. Only larval and pupae state is reviewed, but for example adults of several butterfly and moth species use soil as source of minerals. As a review the MS should be more detailed, especially the introduction. As in the discussion the author makes it clear, that litter and soil are significantly different habitat so it should be differentiated in the previous parts of the MS. Also the author manages food sources and habitats as one factor, but these are two different.

Title should be more informative. For first read I thought the paper will contain information about wingless butterflies (and moths). You also include moths in your paper, not only butterflies.

Abstract – the main result in a review should not be a rough estimate.

Introduction needs more detailed information on the role of soil on evolution of other animal(especially arthropode) groups. It should contain information about the pupae and adults of soil related Lepidoptera.

Material and methods has no information about the data/information collection.

Figures in result need to be improved or recreated (both content and quality).

Discussion needs some information how caterpillars and pupae contribute to the diversity of soil fauna.

Detailed comments

Line 13 – “"0" horizon”, Line 23 – “O‐horizons”, Line 82 – “"O" horizon”, Line 429 – “'O' horizon” – use the same if there is no different meaning

Line 16 – in the results there is 23% not “about 25%”.

Line 21-24 – check these two sentences to see if they are not one

Line 29-30 – write down the list and after that discuss each element, why is it important. Reference needed for all three of them.

Line 41-42 – why is that three species so important?

Line 93-97 – This is partly method. Write down in the methods that how and where did you search the papers, what was the search string and what was the criteria to include or exclude in your review (like a prisma flow diagram in a meta-analyses). In the results a short sentence is enough how many papers was found and from that how many was used. Please include the list of used papers as supplementary material.

Section 3.1. – it would be easier to follow, if you create clear categories of food sources and habitats used by caterpillars and pupae in the introduction and after that use that structure in results. It is not clear sometimes that you are writing about food sources or habitats of caterpillars.

Line 119-121 – this should be in the introduction and needs reference.

Line 132-133 – “benefiting from triple protection of soil, thermal and humidity buffer, and ants themselves as antipredator” – this is not result, move it to introduction or discussion.

Figure 1 – quality should be improved. It is 2 figures placed next to each other. Not clear that it is one tree – create it as one. Colours and pictograms are double coding so one of them is not needed. Colour intensity – how many levels do you have? It is hard to distinguish if it is not next to each other. You should show the number of species in each clad, as you write percentage of species in the text.

Figure 2 – quality should be improved. Colours and pictograms are double coding so one of them is not needed.

Section 3.2. – some places you write such as “food of the caterpillars is not very clear” – maybe some of the excluded specialized papers have information on it.

Line 158-161 – this should be in the introduction as common ancestors of Lepidoptera.

Figure 3 and 4 – all figures must be referenced in the text

Line 367-375 – this is not result

Line 377 – don’t use “presented in Table X”, write down the result and after that refer to the table.

Table 1 – Column 1 is column 2, column 2 is column 3-5 and column 3 is column 6-8. Should be on one page or repeat the header on every page.

Line 401-413 – include reference for known information

Line 423 – “There do not appear to be any caterpillars with modified burrowing legs” – reference needed

Line 433-434 – is there any animal (especially insect) group where soil relation follows evolutional logic? If yes discuss it.

Line 494-497 – “Lepidoptera are 100% aerial insects” – if you write this in an educational magazine, then it is OK. But in academic, I think so that it is clear, that every life stage is important from ecological viewpoint. There is no connection with soil related lepidopterans and frass amount in the soil, as most of the insect faeces lands on the surface of the soil.

Author Response

Response to R1:

Please find my corrected version of my manuscript. In the file, there is first the version with the tracked corrections and then, in the same file, the "cleaned" version where all my corrections have been accepted (depending on the reviewers, some people prefer to see the correction steps, others the final result after corrections).

Thank you very much to the reviewer for this very detailed work and especially for seeking to improve the structure of my work. I have tried to take into account all the comments/criticisms/suggestions or in the worst case explain why I did not fully follow the recommendations. I had made the mistake of not using a bibliography management system, so I had to review the whole bibliography and this allowed me to correct a few typos in it.

General comments

The MS gives us information about soil related Lepidoptera species and what is the evolutionary logic behind it.

Only larval and pupae state is reviewed, but for example adults of several butterfly and moth species use soil as source of minerals.

This important behavior only exists for males and is not obligatory in the ontogeny of species. This will be not treated in this work but now mentionned in Introduction (I cite a paper of Molleman for the physiological point of view and one book of mine as for all the species considered, I was take care to indicate if males are using mud or not).

As a review the MS should be more detailed, especially the introduction. As in the discussion the author makes it clear, that litter and soil are significantly different habitat so it should be differentiated in the previous parts of the MS. Also the author manages food sources and habitats as one factor, but these are two different.

I understand your point of view and it is true that this is one of the main conclusions. For this reason, I propose to mention that the separation of litter/deep soil and habitat/food will be part of the main objectives of this work in the introduction and that, in the light of the results, it will be possible to clarify the interactions with soil in discussion. Text in the introduction and discussion is added to help the flow and understanding of this logic.

Title should be more informative. For first read I thought the paper will contain information about wingless butterflies (and moths). You also include moths in your paper, not only butterflies.

Title is changed

Abstract – the main result in a review should not be a rough estimate.

Corrected/Removed

Introduction needs more detailed information on the role of soil on evolution of other animal(especially arthropode) groups. It should contain information about the pupae and adults of soil related Lepidoptera.

There does not seem to be any specific work on the evolution/phylogeny of arthropods in relation to soil. The only existing work is on beetles (and now cited). The other works describe the species living in the soil and/or count them but not in an evolutionary logic. A paragraph has been added on this topic. So of course nothing was published specifically on Lepidoptera following an evolutionary logic. The articles describing the life traits of the different families are part of the results of this work and are therefore not cited in the introduction.

Material and methods has no information about the data/information collection.

These elements were given at the beginning of the results. I moved this informative paragraph in Material and methods.

Figures in result need to be improved or recreated (both content and quality).

Figure 1 totally corrected

Discussion needs some information how caterpillars and pupae contribute to the diversity of soil fauna.

A short paragraph was added for both caterpillars and chrysalids in discussion (including references)

Detailed comments

Line 13 – “"0" horizon”, Line 23 – “O‐horizons”, Line 82 – “"O" horizon”, Line 429 – “'O' horizon” – use the same if there is no different meaning

Homogeneized

Line 16 – in the results there is 23% not “about 25%”.

You are right it wasn’t clear. The calcul (but knowing that it is an estimation) gave me 22.7% and in the text I was rounding it at 23% and in table at 22.5%. I change for 22.7% everywhere.

The 25% come from that most of caterpillars using soil pupate also in it. I changed a bit a sentence (end of results section) to clarify the origin of this final value.

The other value of 23% is coming from litterature and concern globally invertabrates.

Line 21-24 – check these two sentences to see if they are not one

Done

Line 29-30 – write down the list and after that discuss each element, why is it important. Reference needed for all three of them.

More elements and citations are now given.

Line 41-42 – why is that three species so important?

Due to extreme cold climate.

Line 93-97 – This is partly method. Write down in the methods that how and where did you search the papers, what was the search string and what was the criteria to include or exclude in your review (like a prisma flow diagram in a meta-analyses). In the results a short sentence is enough how many papers was found and from that how many was used. Please include the list of used papers as supplementary material.

Sorry no idea of what is a prisma flow. I just read 400/500 papers and keep the 150 more relevant (equilibrium between being recent and/or most informative) to include in the bibliography of this work (so no need to repeat citation in supplementary material as they are included in references).

Section 3.1. – it would be easier to follow, if you create clear categories of food sources and habitats used by caterpillars and pupae in the introduction and after that use that structure in results. It is not clear sometimes that you are writing about food sources or habitats of caterpillars.

As mentioned above, this is only valid for caterpillars and is a result that is considered in the discussion section.

Line 119-121 – this should be in the introduction and needs reference.

Moved in introduction

Line 132-133 – “benefiting from triple protection of soil, thermal and humidity buffer, and ants themselves as antipredator” – this is not result, move it to introduction or discussion.

Moved in discussion

Figure 1 – quality should be improved. It is 2 figures placed next to each other. Not clear that it is one tree – create it as one. Colours and pictograms are double coding so one of them is not needed. Colour intensity – how many levels do you have? It is hard to distinguish if it is not next to each other. You should show the number of species in each clad, as you write percentage of species in the text.

Figure 1 has been reworked in the hope that it will be easier to read. The double coding has been removed, 3 levels are considered; white: 0%, pastel colour below 40%, intense colour > 40% (explanation now included in the legend). The number of species in an already complex figure would be difficult to read. For each subdivision, the number of species described is given in the text and included in the final table of results for subdivisions with soil interactions.

Figure 2 – quality should be improved. Colours and pictograms are double coding so one of them is not needed.

Figure simplified

Section 3.2. – some places you write such as “food of the caterpillars is not very clear” – maybe some of the excluded specialized papers have information on it.

This is one of the problems encountered. Indeed, in several articles (cited in this work for the different subdivisions), the authors mention: feeding on litter and/or mycelium (without further precision). I think that mycelium represents a much more widespread source of food than the sole use of litter (at least for some families that I know a little better like the Gelechioidea). But you have to understand that in more than three quarters of the articles, the mention of food or living environment is one sentence lost in a 40 page taxonomy article. This is also why it is very difficult to separate food type and living environment. Finally the only separation I tried to inform is not to mix the surface horizon (litter) and the actual soil.

Line 158-161 – this should be in the introduction as common ancestors of Lepidoptera.

Moved in introduction

Figure 3 and 4 – all figures must be referenced in the text

Thanks to spot it. Done

Line 367-375 – this is not result

Agree, this paragraph is now moved in discussion

Line 377 – don’t use “presented in Table X”, write down the result and after that refer to the table.

Corrected

Table 1 – Column 1 is column 2, column 2 is column 3-5 and column 3 is column 6-8. Should be on one page or repeat the header on every page.

Numbering of column corrected. I suppose that for the final version, journal editors will manage not to split the table.

Line 401-413 – include reference for known information

Right ! It was missing even if references were already mentionned in the text (mainly in introduction)

Line 423 – “There do not appear to be any caterpillars with modified burrowing legs” – reference needed

For this point, I have not found any description of a caterpillar with modified legs among all the morphological studies I have read (no reference). However, I remain moderate in my assertion, it is not impossible that among the species of Hepialidae that possess a sclerotized head and that feed on roots that some remain to be discovered with such modified legs.

Line 433-434 – is there any animal (especially insect) group where soil relation follows evolutional logic? If yes discuss it.

You are right it was missing. I add a paragraph in the end of discussion with two references

Line 494-497 – “Lepidoptera are 100% aerial insects” – if you write this in an educational magazine, then it is OK. But in academic, I think so that it is clear, that every life stage is important from ecological viewpoint. There is no connection with soil related lepidopterans and frass amount in the soil, as most of the insect faeces lands on the surface of the soil.

Sentence reformulated

Reviewer 2 Report

I find that the paper shows an original approach to the study of Lepidoptera. I think it offers an understudied view of the ecological and ethological aspects of this taxon. The review work is very thorough and offers many food for thought for new field research on little-studied aspects.

I have only one piece of advice: in the Materials and Methods chapter, the criteria with which the discrete values were chosen are unclear, at least to me.

Author Response

Response to R2

Please find my corrected version of my manuscript. In the file, there is first the version with the tracked corrections and then, in the same file, the "cleaned" version where all my corrections have been accepted (depending on the reviewers, some people prefer to see the correction steps, others the final result after corrections).

I find that the paper shows an original approach to the study of Lepidoptera. I think it offers an understudied view of the ecological and ethological aspects of this taxon. The review work is very thorough and offers many food for thought for new field research on little-studied aspects.

Thanks a lot for your very positive opinion.

I have only one piece of advice: in the Materials and Methods chapter, the criteria with which the discrete values were chosen are unclear, at least to me.

A brief clarification is now provided in the materials and methods.

Round 2

Reviewer 1 Report

The manuscript has been greatly improved, I have only four minor remarks:

Figure 1/B – the family names are hard to read because of low quality

Sometimes you use Fig. 1., other times Figure 1., the latter is better for me.

For PRISMA flow diagram see: https://doi.org/10.1371/journal.pmed.1000097

Line 431-448 - you misunderstood my intention. “Presented in table X” is the proper English formula, but its use should be avoided. Line 431-440 – most of this information should be in the title of Table 1. Line 441-448 – these are the results and after every statement should be indicated, that this information can be found in Table 1.

Author Response

The manuscript has been greatly improved, I have only four minor remarks:

Thank you very much for your comments, your review was very thorough and I am sure your suggestions have improved my work.

Figure 1/B – the family names are hard to read because of low quality

The names have been rewritten for better readability

Sometimes you use Fig. 1., other times Figure 1., the latter is better for me.

Thanks to spot this detail. Corrected

For PRISMA flow diagram see: https://doi.org/10.1371/journal.pmed.1000097

Thank you for the link, very interesting. I also applied my criteria to make this review and I thought of citing the paper you gave me, because finally my selection logic was quite close to the PRISMA model. But in the end, I gave up citing it because it meant renumbering all the other papers. Nevertheless, for more clarity on my selection criteria I have modified my text to show step by step the logic of my selection. I hope this will be clearer for the reader.

Line 431-448 - you misunderstood my intention. “Presented in table X” is the proper English formula, but its use should be avoided. Line 431-440 – most of this information should be in the title of Table 1. Line 441-448 – these are the results and after every statement should be indicated, that this information can be found in Table 1.

The beginning of the information (e.g. line 431-440) is placed in the legend of table 1 and the table is cited in the remaining text in the result section.