Substrate Selection of Ascidian Larva: Wettability and Nano-Structures

Round 1

Reviewer 1 Report

This manuscript discusses the substrate selection of ascidian and other larvae with regard to wettability and nano-structures with focus on the 'silicone paradox', the finding that some larvae clearly select hydrophobic surfaces that are fouling-resistant. The authors propose a 'flypaper' method of control of fouling organisms. This is a very interesting suggestion that could greatly benefit aquaculture efficiency, and should be tested immediately.

The manuscript should note that there has apparently been selection for settlement on textured surfaces since the Cambrian Period (see Fig. 4o in Can. J. Earth Sci. 58: 495–504 (2021) dx.doi.org/10.1139/cjes-2020-0167).

Comments on the manuscript:

line 68 replace 'effecting on' with 'influencing'

lines 212-226 Discussion should be added here about the hydrophobic character (or otherwise) of mollusk periostracum, a naturally occurring aquatic surface.

line 275 replace 'fouling on' with 'fouling of'

line 323 replace 'is what' with 'is which'

 

Author Response

Thank you for your review.

The manuscript should note that there has apparently been selection for settlement on textured surfaces since the Cambrian Period (see Fig. 4o in Can. J. Earth Sci. 58: 495–504 (2021) dx.doi.org/10.1139/cjes-2020-0167).

We checked the suggested reference. The organism in Fig. 4O is regarded as colonial animals in the report, and this do not show the  aggregating settlement of individuals. We cannot conclude that this may be an evidence of selective settlement. The trace of the texture is micro-scale round tubercles and not nano-scale structures mainly discussed in our review. We did not mention this article in this review.

line 68 replace 'effecting on' with 'influencing'

We corrected as suggested.

lines 212-226 Discussion should be added here about the hydrophobic character (or otherwise) of mollusk periostracum, a naturally occurring aquatic surface.

We surveyed literatures on the function of molluscan periostracum, but could not find suitable report for the discussion of the present topic. If the animals has hydrophobic body surface in the larval stage, this feature may enhance dispersal via drifting on the water surface. This is not directly related with the settlement.

line 275 replace 'fouling on' with 'fouling of'

We corrected as suggested.

line 323 replace 'is what' with 'is which'

We corrected as suggested.

Reviewer 2 Report

I read and revised the article JMSE-1246280 and it gathers information about some works developed, including by the authors, about the testing of different substrates and the fixation of ascidian larvae. The paper is well writen and is easy to read, gathering interesting data.
I would like to suggest the inclusion, although not mandatory, of conclusions, which bring together and summarize the main advances made recently and what the future perspectives are in terms of testing strategies and applications.
I also advise authors to carefully review the text, as in some cases the spacing between words is double-spaced, for example. I also ask you to review the article formatting rules, as, for example, in the figure captions, the text must be justified and not centered.

Author Response

Thank you for the review.

I would like to suggest the inclusion, although not mandatory, of conclusions, which bring together and summarize the main advances made recently and what the future perspectives are in terms of testing strategies and applications.

Thank you for the suggestion. We did not change this time. We wished to place a proposal of the potential use of hydrophobic flypaper at the ending in this review.

I also advise authors to carefully review the text, as in some cases the spacing between words is double-spaced, for example. I also ask you to review the article formatting rules, as, for example, in the figure captions, the text must be justified and not centered.

We deleted double-space between words. As for the figure captions, we had selected MDPI_5.1.1_one_figure_caption in the styles. We changed it to DPI_5.1_figure_caption

Reviewer 3 Report

By making use of epxerimental and bibliographic data the authors propose the use of hydrophobic substrates near aquaculture facilities to mitigate their biofouling due to the reduced water-wettability of such surfaces. They also propose that the effect of these hydrophobic substrates against biofouling can be further amplified if these surface are characterized by nano-irregularities.

Overall, I find their review comprehensive even to non-experts and well written. I also find their mechanical approach worth exploring especially if it can help to reduce environmental polluting chemical approaches to any degree.

My only comment is on the resolution quality of the figures. They appear pixeled in the pdf but this may be due to pdf's downsampling scripts. Please provide high resolution images if possible. 

Author Response

Thank you for the review.

We will provide the original figure file with the revised manuscripts.