Mate Choice in Molluscs of the Genus Littorina (Gastropoda: Littorinidae) from White Sea

Round 1

Reviewer 1 Report

Review of Kozminsky et al “Mate choice in mollusks of the genus Littorina (Gastropoda: Littorinidae) from White Sea

Gastropod mollusks of the genus Littorina served as a model species for the study of mate choice in many areas of their distribution (especially Spain, Sweden, and Britain), but up to now such studies were lacking for the White Sea populations in north-western Russia.  Manuscript by Kozminsky et al. fills this gap nicely by exploring mate choice in three species of Littorina, L. saxatilis, l. obtusata,  and L. fabalis, with regard to their size. The authors find an evidence of positive size-assortative mating in L. saxatilis and L. fabalis, but not in L. obtusata, but the latter species exhibited evidence of sexual selection in favor of larger females.

This paper is well-structured and well-written. The study uses adequate collection methods, sample size, and appropriate statistical analyses. The results are nicely summarized in two figures and one table. Discussion appropriately interprets results and provides comparison to the available literature on this subject.

Among major changes, order of Figures should be changed; now Fig. 2 is shown before Fig. 1. Listed below are some minor suggestions and corrections of typos or styles.  I recommend this paper for publication after minor revision.

 

Minor suggestions

 

Line 11: Insert space between genus (L.)  and a specific epithet. That is, change ‘L.saxatilis’ into ‘L. saxatilis’, etc.

Line 11: Change ‘u’ into  ‘and’ before L. fabalis.

Line 49: Change ‘Littorina saxatilis’ to ‘L. saxatilis’. Insert space after period in ‘L.fabalis’

Line 50: Change ‘estableshed’ into ‘established’

Line 65. Insert period after ‘value’

Line 101: Correct ‘in in’. Keep just one ‘in’

Lines 137-138:  According to this sentence the smallest diameter of copulating L. saxatilis female shell was 3.3 mm, but on Figure 1 it is less than 3 mm. Make figure and text consistent.

Line 143: Make sure that alpha character is correctly represented

Line 149: Change ‘made up’ into ‘was’

Line 179: Do not use parentheses to enclose ‘Table 1’

Line 350: Use italic font for species names, L. saxatilis and L. fabalis.

Figure 2 is shown before Figure 1. Change their order of presentation.

 

Figure 1. Figures would be easier to interpret if the same scale is used for the diameter of shells on X and Y axes. Additionally, note that the same values (e.g.’4,4’ or ‘5,5’, etc) are shown on X-axis for L. saxatilis; these should be changed to appropriate precision levels.

References.

Make sure that DOI citations are consistent for all references. For example, Refs 3, 6, and 11 use different styles of DOI citation. Style of the Ref 6 is preferred

Ref 8, Ref 12, Ref 16: Do not start each word in the article title with a capital letter.

Ref 14. Use italic font for ‘Littorina neglecta’

Ref 37. Use lowercase letter in ‘Choice’

Ref 44: Insert space in ‘sizeadvantage’

Author Response

We have taken into account all the wishes of the reviewer.

There is only one remark to be noted:

Lines 137-138: According to this sentence the smallest diameter of copulating L. saxatilis female shell was 3.3 mm, but on Figure 1 it is less than 3 mm. Make figure and text consistent.

Response 137-138:

One of the copulating LS females had a shell diameter of 2.9 mm but an underdeveloped reproductive system. Since this female was involved in copulation, we left her in the analysis. To make figure and text consistent, we added a footnote:

«It should note we also found one copulating L. saxatilis female with a shell diameter of 2.9 mm, which, however, had an underdeveloped reproductive system. Since this female was involved in copulation, we left her in the analysis.»

 

We take this opportunity to thank the reviewer for the critical remarks made.

Reviewer 2 Report

Major comments

This study utilizes the well-studied model group, the genus Littorina, and complements its research findings. The methodology is scientifically sound, and both the results and discussion follow well from previous studies.

 

Minor comments

Abstract

L11 иmay be typo.

L109 It would be preferable to write a reason and citation to exclude those infected with this parasite.

Author Response

Line 11: и may be typo.

Response 11: The typo has been corrected.

 

Line 109: It would be preferable to write a reason and citation to exclude those infected with this parasite.

Response 109: Infected females were recorded in the analysis, since, according to our observations, the individuals of the active sex, the males, did not distinguish between infected and uninfected females. We write about it below (first paragraph «Results» of new version of manuscript).

 

We take this opportunity to thank the reviewer for the critical remarks made.

Reviewer 3 Report

The manuscript described study on the reproductive behaviour associated with the mate choice by size in three species of periwinkles from the White Sea (Littorina saxatilis, L. obtusata and L. fabali). The research was carried out on a large number of individuals, which allowed to obtain reliable results. The size of individuals was determined on the basis of diameter only, were other parameters measured? such as shell length? Species specific differences of the males choice were the most interesting results. Three models of reproductive behaviour were described and discussed.

minor corrections:

The insertion of a figure with shells of three species would improve the manuscript

78-89 - first paragraph of the Material and Methods should be moved to Introduction.

49 - L.fabalis - L. fabalis

110-117 – this are the results

355 - L. saxatilis and L. fabalis - L. saxatilis and L. fabalis

Author Response

Comment: The size of individuals was determined on the basis of diameter only, were other parameters measured? such as shell length?

Response:

Only the diameter was used in the analysis. Since the shell diameter of L. obtusata and L. fabalis is greater than the height, this parameter was chosen as more sensitive. In the case of L. saxatrilis, the shell diameter was also used - for comparison with the other two species.

 

Minor suggestions: a figure with shells of three species, Lines 49, 110-117, 350.

Response: All of these suggestions have been taken into account.

 

Lines 78-89: first paragraph of the Material and Methods should be moved to Introduction.

Response 78-89: We think that this paragraph is best left in “Materials and Methods”, because this paragraph describes the specific species of Littorinae that were studied in this work. At the same time, “Introduction” is devoted to general issues affecting a wider range of littorinas and other animals. Therefore, this paragraph will be out of the general style of this section.

 

We take this opportunity to thank the reviewer for the critical remarks made.