Note on the scope of my review:
My area of expertise is outside the scope of this document, as I usually study ochre in the prehistoric context from the angle of analytical chemistry. Thus, my opinion will only concern the accordance of this paper with the journal’s topic, the article structure and presentation. The cited literature has mostly been not checked. As an external scientist, I will give a general opinion on the approach and its robustness.

Summary
Based on the statistical study of a large collection of archaeological data, this article uses the behavioral ecology models of Costly Signaling Theory (CST) and Economic Defensibility Model (EDM) and its counterpart Social Boundary Defense (SBD) to explain shifts in the symbolic signaling behavior of hunter-gatherers at Blomplaas Cave in South Africa during the Last Glacial Maximum and the Last Glacial-Interglacial Transition. The approach relies on a robust methodology of testing hypothesis against the available data to link these observations to social and environmental shifts. The paper introduces the interest of the deductive approach proposed and then present it.

The EDM model explains a local reporting strategy, while the SBD model better explains a regional reporting shared by several social groups. To establish which of these two models best fits the data collected according to temporal and environmental contexts, these are evaluated using the CST approach. Two hypotheses are tested in this way:
- Changes in symbolic production (ochres and beads) observed locally follow those observed regionally.
If this is not the case, then EDM is preferred to explain symbolic behavior in Boomplaas and the region.
- Local symbolic production changes in the same way as local variations in symbolic behavior, generated by a variation in the availability of dense, predictable resources.
If this is indeed the case, then it is probably local ecological variation that has influenced symbolic behavior at Boomplaas Cave.
The paper takes into account the impact of taphonomy on the archaeological data used, and assumes that they reflect a larger but coherent set that has now disappeared.
The background section introduces the geo-chronological situation of the cave in its regional context. In particular, the environmental features and changes due to the coastline relocation are presented, along with the occupation of regional sites over time, allowing to deduce trends in population density possibly driven by ecological changes. In a second part, the history of the cave excavation and study are presented.
Then comes the Methods section, in which the data binary variables are introduced and explained, as well as the statistical tool employed. The signaling behavior is mostly studied from the perspective of ochre usage at Boomplaas Cave. The retained descriptors are the provenance of the ochre (endo- or exogenous), the presence of diverse ochre-processing traces, the color (yellowish/reddish), the extent of the processing traces. In addition, the frequence of ostrich eggshell beads are recorded as it reflects the use of signaling devices, the frequency of sicrete as a material gathered remotely, and the presence of gregarious grazer remains as an indicator of the dense and predictable resources. All these descriptors are presented in form of a ratio for each member of the stratigraphy and processed with Cochran-Armitage trend tests. It is well suited to highlight a trend between two-classes variables (the descriptors previously presented), and a K-class variable (the stratigraphy members). In other word, these tests allow to describe the evolution (or not) of the presence of gregarious grazer remains/worked ochres/local ochres and so on along the stratigraphy.
The results of theses tests are then presented, revealing several tendencies. First the diminution of the ratio of gregarious grazers, meaning a depletion of the dense and predictable resource for the prehistoric people. Second, the absence of silcrete lithic except at the end of LGM with a peak at 50%. Third, variation in ochre procurement (exo/endo) and use (traces of work). Fourth, a shift in ochre preferred color as well as the progressive use of ostrich eggshell beads. Taphonomies processes are discussed to ensure that the results are significant.
Finally, the initial hypothesis are tested in the light of these results and the connections between local and regional dynamics.

Is the scope of the paper corresponding to the topics of the journal?
This article is well suited to be published in Archaeometry due to its topic: the study of ancient human behavior, as well as the archaeological and biological nature of the data used. The methodology employed is also in the scope of this journal as it uses statistics and biological anthropology models. The overall quality of the described works appears very satisfying and within the standards of this Journal.

Is this paper of national/international significance?
I do not know enough the field of paleoanthropology to give a final answer to this question, but in my opinion it is. Indeed, the paper brings information about the behavior of humans at Boomplaas cave, linked to a regional context. It follows a methodology that, from my point of view, seems new.

Article organization
Concerning the background section, it is surprising for me to find original radiocarbon dating results presented, processed and contextualized here. These are generally expected to figure in a ‘results and discussion’ section rather than in the background. I believe that this section is very clear and critical for the comprehension of the paper, and I do not see how to present the dating in a different way, yet it could be a plus to highlight them more effectively.

Statistics
For verification purpose, the raw data (used in 3. Methods) could be included in the supplementary information, and the sample size for each descriptor cited in the text. The redirection toward different papers through the literature to find this information can be exhausting. In a last resort, the given p-values are a good indicator of the robustness of the dataset and conclusions made.

Visual considerations
A figure could help to improve the comprehension of the synopsis, the data processing and summarize the data variables used.
The images resolution should be improved.

Other
L443: explicit OES : Ostrich eggshell

Conclusion:
This article appears me to be rich, both in the methods employed and results obtained. Using an impressive literature review, statistics, behavioral ecology models and logic, applied to data of different nature, the authors build conclusions from a material to an abstract (symbolic behavior) point of view. The conclusions are always finely justified when several explanations are possible. Therefore, I recommend the publication of this article in Archaeometry.