The Travelling Salesbaboon: Chacma Baboon Route Efficiency in Multi-Stop Daily Travel Routes

Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsThe author presented a novel technique for calculating the efficiency of chacma baboons' daily trips. Despite its limitations, which the authors emphasized, the technique has the potential for improvement. It would be a very useful tool for studying primate behavior. Therefore, the manuscript at hand is of high scientific value.
The main question addressed by the research was whether the baboons followed the nearest neighbor heuristic or the optimal (least distance) route during their daily movements.
The research is considered novel as it applied a novel technique. Also, it provided experimental evidence about the movements of baboons. The subject of this research is suitable for Wild because it concerns aspects of primate behavioral biology.
The manuscript text conveys the author’s thoughts clearly and unambiguously. The theory underlying the research has been succinctly given. Research design, data collection, handling, and analysis have been carried out using proper methods. The data has been appropriately interpreted.
The research questions were elaborately addressed by a specific experiment. The manuscript has included all the relevant references. Tables and Figures are useful and nicely laid out. The quality of the data supports the analysis and conclusions. All arguments and conclusions have been supported by relevant references.
Overall, the research design, analysis, and discussion have been very well carried out, in line with the produced evidence. The manuscript presented novel research that can be considered a significant contribution to the field of primate behavior.
Minor comments
Give the scientific name only when a species is first referred to in the manuscript.
Line 129: 5x5 m grid…
Author Response
Thank you for taking the time to review this manuscript and for your feedback. Please find detailed responses below and the corresponding revisions in track changes in the re-submitted files.
Comment 1: Give the scientific name only when a species is first referred to in the manuscript.
Response 1: Thank you for pointing this out. I have removed duplications of scientific names throughout the manuscript.
Comment 2: Line 129: 5x5 m grid…
Response 2: I agree that this line was ambiguous; I have revised to wording to make it clear that the feeding stations were arranged in a 5x5 pattern with 1.53 metres between each station
Reviewer 2 Report
Comments and Suggestions for AuthorsThe Travelling Sales baboon: Chacma baboon route efficiency 2 in multi-stop daily travel routes. Wild-3454151.
The aim of this study was to determine the efficiency of the daily movements of two groups of Chacma baboons in areas of Gorongosa National Park, Mozambique. GPS-based routes were obtained and compared with two methods, the nearest neighbour method and the Concorde algorithm. The proposal is interesting but suffers from several problems. The introduction is very long and needs to be reduced by eliminating some redundant points. The methodology needs several clarifications, starting with the characterisation of the areas and the objects of study. It is suggested that the notes in the manuscript be taken into account.
Abstract
Lines 34-37. Seasonal resources may also be predictable.
Line 37. Only females? Why only females?
Line 39. Two per group or four per group?
Line 50. Key words should be different from those in the title.
The introduction
Line 59. Give some more references.
Line 63. Explain this further if you think it is relevant to the aim of the study.
Lines 71-73. Give some examples from these few papers.
Line 76. Missing references on this topic.
Line 105. This seems to contradict what is said two paragraphs earlier (lines 71-73).
Lines 113-114. Examples where TSP is mentioned in biological problems.
Line 118. Missing reference.
Line 118-122. Rather than explaining the bee study in detail, it is better to give references to more examples.
Lines 125-130. The introduction is long and this part has already been mentioned in a previous paragraph (lines 88-104). I think information could be gathered and the paragraph restructured to make the introduction a little shorter.
Line 131. What studies are you referring to?
Line 132. Are they referring to primates?
Line 134. What scenario are you referring to?
Line 137. Which one?
Line 145. What challenges?
Line 152. Why do you want that we see these references?
Line 157. Specify which studies.
Line 160. Specify which ones.
Line 161. More recent than which?
Line 164. Which problem?
Line 172. In what sense is it obstructed?
Line 177. What problems?
Line 178. It seems to me that the mention of placing GPS in primates has already been mentioned in previous paragraphs, albeit in a more general way. I think that the paragraphs could be combined and it might be another way of reducing the introduction.
Line 184. Was it 332 consecutive days?
Line 185. How did you know they were resource patches? What type?
Methods
Line 204. Why females and why only two?
Line 208. What does this habituation refer to? Habituation to what?
Line 210. I suggest not starting the paragraph with an abbreviation.
Line 218. A reference is missing.
Line 219. Why are there three times as many baboons in the WT area, which is smaller than the FT area?
Line 229. A reference is missing.
Line 194. Study sites and subjects. This section lacks information on the baboons' reproductive period, e.g. mating, gestation, lactation. There is also no information on the formation of social groups or subgroups and dominance hierarchies.
Line 233. How were the animals anaesthetised? How were the anaesthetised females selected? Were morphometric data recorded?
Line 236. I suggest including a table with the morphometric data of the four females by study area and days of recording. The maximum lifespan of the collars (323 days) is less than the total number of days mentioned in the introduction (332 days).
Lines 236-240. This paragraph is unclear. The data were downloaded remotely in certain periods totalling seven months. Is the information from these months analysed? Why only those? Please specify.
Line 245. Why was the night data discarded?
Lines 249-250. The period from 02:00 on one day to 02:00 on the next day includes night hours, so it is not clear which period was actually used for the analysis.
Line 258. Were all of these resources included in the analyses?
Lines 286-292. Can a reference be included to support this methodology?
Line 317. What does this data manipulation refer to?
Results
Line 347. In reality, the underestimation is very obvious.
Lines 388-393. Why pool the data from the four individuals when they are two different groups with different habitat characteristics, group size and home ranges? They should be analysed separately to compare the two groups and then discussed.
Discusion
Lines 422-423. This information is not consistent with the data presented in Table 1.
Line 424. Why did the two individuals from each group not visit the same waypoints?
Lines 457-459. This would suggest that the individuals from each group might have similar information.
Lines 459-460. For this text it is important to describe the characteristics of the social group and to know more about leaders and decision making.
Lines 469-471. How are the waypoints distributed throughout the day? Knowing this could help resolve doubts about the baboons' behaviour over time and by location.
Lines 478 and 480. I think these are not really false waypoints, but rather new points.
Lines 482-485. Solving this is the aim of the study, so why not include all this in the study?
Lines 488-490. Exactly, so why not include some of these variables in the analysis?
Line 491. In fact they were not observed.
Line 492. It was not known for sure.
Lines 494-496. The description of each area is very general, the distribution of the vegetation is not known (e.g. a map).
Line 511. Why was the predator density considered low? Any evidence?
Lines 514-515. Is there any reference to support this statement?
Line 520. The description of the zones gave the approximate number of baboons per zone, but not the number of troops in each zone.
Line 527. More than 300 days of recording implies more than 10 months of sampling, so one might think that information is available for the wet and dry seasons. This should be clarified in the proposed table with information for each female with GPS.
Lines 531-532. Here a comparison is made between the two study areas and the habitat characteristics are mentioned, but the results do not separate the information between the sites. The results of the surveys do not distinguish between the two study areas either, it is important to have this information to be able to have this part of the discussion.
Lines 533-539. Again, to understand this part of the discussion it is necessary to have the results of the routes and polygons in relation to the habitat characteristics of each area.
Comments for author File: Comments.pdf
Author Response
Please see the attachment
Author Response File: Author Response.pdf
Reviewer 3 Report
Comments and Suggestions for AuthorsThis paper presents a new method of assessing animal waypoints and route optimality from GPS collar data collected on four individual baboons. The authors frame the paper around the Traveling Saleperson Problem (TSP) and examine baboon daily paths across their natural range relative to some commonly assessed heuristic strategies and the shortest overall route. They find that their collared baboons take routes that are more efficient than those predicted by the nearest neighbour rule, and come close to optimality, especially when the number of targets are fewer in a day.
Overall, I found the paper to be fairly well written and executed. I think that the method used by the authors will be of interest to others that are also working with collared animals. My main comment is that the paper could be clearer regarding the definitions it uses. I have detailed where confusion arises because of definition issues below and I give some other relatively minor comments regarding the writing.
With regard to definition issues. In the abstract (L 43) it states that the nearest neighbour rule requires individuals to travel back to the start of a route. This is incorrect and should be deleted here, although this is a requirement of the TSP. Around lines 169 and down to about 190, and again on lines 247-249, I was confused as to whether these baboons always sleep on the same cliff, or whether they have multiple sleeping sites. It seems from the description that they do have multiple sleeping sites, and so the authors are not truly testing whether the baboons can solve a TSP but rather an Open-TSP or a Hamiltonian Path Problem (or a Shortest Path Problem). I think they need to be more up front about this earlier and define for the reader the difference between central place foragers and non-central place foragers (See Teichroeb and Smeltzer 2018, cited below for more guidance on this). Perhaps they were trying to make it less complicated for readers but for those that know the definitions of these concepts, the way it is quite confusing.
I was wondering how the authors accounted for the fact that in a group foraging scenario, contest competition often makes it so that an individual cannot go to the nearest neighbouring resource because it is already occupied by a dominant. I see that in the description of how resources (or waypoints) were retrospectively defined, that these are so large that competition is unlikely to be an issue. But perhaps the authors want to mention this at some point in the manuscript.
I like that the authors have conceived of all foraging, resting, sheltering, and socializing sites as “resources” (L 258). However, I think this may be controversial to some. It would be useful if they elaborated on this decision somewhere in the Introduction.
Minor comments:
L 59 – Change “as to” to “of”.
L 63 – Change “impactors” to “factors”.
L 75 – Add “of” after “question”.
L 84 – Because it was previously mentioned, Alouatta here could be changed to just A.
L 101 – Add a comma after “ knowledge”.
- 117 – The “and” in the parentheses should not be italicized, and the second Bombus could be changed to B.
L 121 – The species name should be italicized and the Bombus can be changed to B.
L 128-129 – For my own work, I actually went back to Audrey Cramer’s dissertation at one point and she sourced her monkeys from an area where they would have been Chlorocebus sabeus and not C. pygerythrus.
L 140 – I recommend adding “a” before “cluster strategy” and “the” before “convex hull”.
L 142 – The reference #37 is incorrect. This should be Teichroeb & Smeltzer 2018 in PloS ONE
- https://doi.org/10.1371/journal.pone.0198076
. In addition, we did find that some animals consistently found the optimal route in that study and showed evidence of planning their routes, so this line needs to be edited.
L 146 - The “and” in the parentheses should not be italicized, and the second Saguinus could be changed to S.
L 153 – The first parenthesis can be deleted.
L 199 – Change “mammal” to “mammalian”.
L 211 and 219 – The 2’s should be represented as exponents.
L 295 – RStudio should be cited.
L 302-303 and 306-307 – This is only true if the monkeys are having to solve a true TSP, which they are not.
L 326-329 – This information needs to be presented earlier for clarity.
L 417 – It says “linear TSP” here. Is this the same as “open TSP” or “Hamiltonian Path Problem”? Again clearer definitions are need.
L 419-420 – I believe in the methods it says “at least 15 minutes”. These should be the same.
The Discussion is nicely written!
Author Response
Please see the attachment
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
Comments and Suggestions for AuthorsI have reviewed the authors' changes to the manuscript and the response letter. In my opinion, the manuscript has been sufficiently improved in each section and new references have been included to better support the interpretation of the results.
Make the following minor suggestions:
Line 359. Correct this. Will they include a thesis statement?
Line 762. Expand the idea of this sentence; it seems incomplete.
Line 765. It's better to say... We show evidence of...
Line 766. Specify the method.
Comments for author File: Comments.pdf
Author Response
Summary:
Thank you again for taking the time to review this manuscript and give your comments and feedback, including for the newly added conclusion. Please find the responses to your comments below and the corresponding revisions in the re-submitted files.
Comments:
Comment 1: Line 359. Correct this. Will they include a thesis statement?
Response 1: Thank you for catching this, which was intended as a placeholder until the correct citation was added to the bibliography. It has now been corrected.
Comment 2: Line 762. Expand the idea of this sentence; it seems incomplete.
Response 2: Thank you for pointing this out. The sentence has been expanded to more fully describe the basis of the research.
Comment 3: Line 765. It's better to say... We show evidence of...
Response 3: Thank you for this feedback. The wording has been changed as you suggested.
Comment 4: Line 766. Specify the method.
Response 4: The last sentence of the conclusion has been divided into two sentences, and the method of identifying AOIs specified.