Peer review of: The first Australian plant foods at Madjedbebe, 65,000–53,000 years ago (2020)

Reviewers' Comments: 
 
Reviewer #1: 
Remarks to the Author: 
This paper presents the earliest archaeobotanical remains for the Sahul region, from the site of 
Madjedbebe in Arnhem Land, Northern Territory. It is rewarding to see this type of archaeobotanical 
analysis being applied to the assemblage from Madjedbebe. Too little is known of what Sahul’s first 
colonists foraging strategies were, particularly in relation to plant remains. Their ability to learn about 
and adapt processing strategies for new plant foods is key to understanding the adaptability, 
innovation and flexibility of these first colonists, and this research is an excellent step towards provide 
this fuller picture of Sahul’s earliest ancestors. At the same time, this research challenges the single 
dimensional coastal adaptation model previously suggested for the Southern Dispersal Route and 
colonization of Sahul. 
 
At times the claims need to be better contextualized in further reading of the literature. In the 
abstract, the authors note that the use of plant foods requiring extensive processing did not occur in 
this region until the Holocene – yet there is evidence for toxic plant processing at Niah Cave in the late 
Pleistocene (see Barker et al 2007 Journal of Human Evolution) and then seed grinding from Australia 
at Lake Mungo from 25-14 kya (Fullagar et al 2015 Archaeology in Oceania) and at Cuddie Springs 
from 30 kya (Fullagar and Field 1997 Antiquity). The claim that the practices at Madjedbebe of being 
more than 40kya older than other such finds in Australia is perhaps a little exaggerated, and also does 
not take into consideration the age range of the Phase 2 finds so changing to 23-35 kya may be more 
accurate. 
 
Further consideration also needs to be considered as to the language used so that conclusions are not 
over-stated: are the plant resources identified in this article really “hard to get” or are they just time 
consuming in processing? They do not appear to be toxic – or are they restricted in 
range/abundance/difficult to obtain? I would apply the same critique to the use of the term “broad-
spectrum”. Are five taxa indicative of broad spectrum plant exploitation? Compared to the more 
numerous species at Niah especially. The Ivane valley is also used to support broad-spectrum plant 
exploitation but there are only two plant species Pandanus and Dioscorea published for this site? Are 
there ethnographic correlates that could be drawn upon here? For example, how does this diet 
compare to the ethnobotanical information collected as part of this project? 
 
Overall the data for the identification of the archaeobotanical remains is presented well and is 
convincing, particularly the proofs – although there are some errors. Page 2 Line 66 – Eight different 
types of plants were recovered from Phase 2 – unclear what is meant by different types here – taxa? 
Or types of plant remains? Page 2 Line 66 – should this be 5 taxa? Curcuma, Buchanania, Canarium, 
Pandanus and Persoonia? Page 4, line 100 – Three taxa should be Four. 
 
Page 4, paragraph 3 and also supplementary Information Section 3 – consistency with plant 
terminology needed as there is switching between drupes, nuts and kernels, particularly for the 
experiment which makes it unclear as to the specific activity being undertaken. Perhaps the overall 
fruit should be identified as a syncarp, then polydrupe or drupe, and kernels for the actual nuts itself? 
See Lim 2012 Edible Medicinal and Non-Medicinal Plants Volume 4: Fruits. 
 
Further information is also required to support some of the statements made. For example “reliable 
access to fats, proteins and starches in a range of habitats”. There is no table included anywhere that 
identifies the dietary/nutritional (or other medicinal) properties of these taxa, nor is there any 
discussion as to what types of habitats that the plants come from. Cucurma in particular also has 
medicinal properties (see Rajkumari and Sanatombi 2018 International Journal of Food Properties) – 

was this apparent in the ethnobotanical knowledge recorded? Or for any of the other species 
identified? 
 
Further to the point above, there is no palaeoenvironmental evidence included that discusses the 
availability of the same vegetation types today as in the past. Or how these vegetation zones have 
changed over time. Is this a potential factor in identifying archaeobotanical remains from the site? 
 
The authors have also noted that Phase 2 is the earliest evidence for human occupation at the site, 
whereas in previous articles (Clarkson et al 2017), there appears to be lithic artefacts at least in Phase 
1. Is it clear that there is no evidence for occupation in Phase 1? Are there any plant remains that 
belong to this phase? 
 
In addition to the archaeobotanical remains, usewear/residue analysis of 29 grinding stones is 
included to assess plant processing at the site. These are very significant artefacts – the oldest in 
Sahul and identifying their use provides another important aspect to our understanding of the 
adaptations and behaviours of Sahul’s earliest colonists. However, this section needs to be presented 
more coherently. To begin with, there are inconsistencies in the total grinding stone numbers used for 
plant processing – in the text of the article, there is at least 8. In SI Section 4, it ranges between 10 
(page 1, Line 129), then 10 in the table if you include the two possibles, then page 2 line 167, there 
are 7, and then in SI Table 6, Line 266 there are 15. In SI Section 4, page 3, line 197 – only 5 
artefacts had plant residues attributed to use. While I appreciate that there are multiple strands of 
evidence being used to analyse these tools, some clarity or resolution is needed for the reader where 
the results of these different analyses are contrasted to either support or reject the tool function. 
 
In the Clarkson et al 2017 article GS32 is identified as a mortar used to process hard plant material. 
Yet this is not discussed in the body of this paper. It is included in the SI Section 4, although if it is 
used as a mortar there appears to be no impact marks in the usewear (Supp Table 4). 
 
There needs to be photographic proofs of experimental/replicative tools used for the suggested use 
activities, particularly for the seed grinding. This level of information is included for the 
archaeobotanical identifications but not for the usewear/residues. What range of 
experiments/activities were undertaken as a comparison for the archaeological tools? This is an 
important section missing from both this and earlier Madjedbebe reports attributing function to 
specific tools. For example, P. spiralis has been recorded ethnographically as ground into a flour – is 
this a potential use that was tested for? At this point, the reader has to take on face value the 
identification of these tools as there is no conclusive proofs given as to their function. 
 
Another worrying issue is that the authors state that pigments appears to be have resulted on the 
grinding stones due to post-depositional or post-excavation handling. Is there a possibility that this 
has occurred with other types of residues, particularly as it appears the animal residues are 
discounted? Again, this comes back to the need to integrate all of the strands of evidence into a more 
coherent picture. 
 
For what grinding stones is there deliberate evidence of shaping? More information is required here. 
 
Overall this is an extremely important site in Sahul’s prehistory and the identification of the activities 
undertaken by our earliest colonists is vital for understanding colonizing strategies, not just for Sahul, 
but for the global domination by modern humans. The focus on plant remains broadens our view of 
these colonists, challenging single dimensional models such as pre-adaptations to Coastal Highways. 
At the same time, this paper shows the need for these types of multidisciplinary approaches to site 
interpretation and is hoped will influence similar types of studies on other sites. The data here is 

important but needs to be presented in more coherent and conclusive detail to fully justify the 
conclusions made. 
 
These comments are largely informal and to do with spelling/grammar issues: 
 
1. Page 7 Figure 4, line 178 c-d should just be c 
2. Page 9, line 285 – spelling of remains 
3. Extended Data Figure 1 – 1972 excavation in figure, 1973 excavation in Caption. 
4. Extended Data Figure 3b – is it possible for a clearer picture? 
5. SI Section 1 line 48 – space between Shelf and (Nix 
6. SI Section 1 line 63 – spelling Zingiberaceae 
7. SI Section 2 – include total NISP 
8. SI Section 4, page 2, line 155 – stone will cause 
9. SI Section 4, page 2, line 159 concave usually indicates 
10. SI Section 4, page 3, line 172 – micro-striations 
11. SI Section 4, page 3, p187 - ultrasonicated 
12. Page 2 Line 72 – spelling of specifically 
13. SI Section 4, page 3, line 173 - the four pigment processing stones are not discussed here and 
appear to be included in the 21 non-diagnostic artefacts. 
 
 
 
Reviewer #2: 
Remarks to the Author: 
The manuscript by Florin et al. presents evidence of plants exploited by the first human inhabitants of 
Sahul, purportedly 65-53kya. The authors further note that some of the plant resources exploited at 
the Madjedbebe rockshelter required labour-intensive processing, thus predating previous evidence for 
this behaviour in Australia by >40ky. This study has potential to influence archaeological narratives in 
Australia and beyond and merits publication in Nature Communications, but I feel that some of the 
claims made by the authors are not sufficiently justified or need further clarification. For this reason, I 
am recommending a major review. Below I describe the points that, in my opinion, the authors would 
need to address in order to improve the manuscript. 
 
• The manuscript has no introduction whatsoever; it goes straight from the abstract to the 
presentation of the results. Although Nature Communication’s guide for authors advices against the 
use of ‘Introduction’ as a heading, this should not preclude the authors from discussing previous 
literature and contextualising their research. 
 
• It is not clear what the actual focus of the manuscript is. If it is the early evidence for the 
consumption of labour-intensive plant resources this should be clearly stated at the beginning of the 
manuscript and the relevant literature (similar evidence for early modern humans worldwide) 
discussed. The groundstone assemblage and the experimental work would also need to be further 
discussed in the main text, as they provide supporting data for the central claim. 
 
• A more robust chronological framework seems necessary to support the authors’ claims. In the first 
place, the disagreement surrounding the date of Madjedbebe’s Phase 2, most notably by Allen (2017) 
and O’Connell et al. (2018), should at least be briefly acknowledged. Clarkson et al. (2018), in a 
response to Allen’s (and others) (2017) comments, show that beyond 1.5m of depth 75% (9 out of 
12) of the charcoal samples submitted for radiocarbon dating did not survive chemical pretreatment 
(Clarkson at al. 2018: Fig. 1), but in this manuscript Florin et al. claim that “attempts to date the plant 
macrofossil remains from Phase 2 have been unsuccessful, dissolving during chemical pretreatment” 

(p. 6, l. 6-7). Whether all charcoal samples from Phase 2 were destroyed during pretreatment or three 
did survive needs, thus, further clarification here. Indeed, 14C-dated charcoal fragments from Phase 2 
presented in Clarkson et al. (2017: Extended Data Figure 8(g)) seem to disagree with the 65-53kya 
OSL ages. Did any of the ‘disagreeing’ 14C dates come from the Phase 2 hearth? Also, have there 
been any attempts to radiocarbon date macrobotanical remains other than charcoal? A ≥50kya 14C 
date on two or more of the plant food remains presented in this study would most definitely provide 
definite evidence to the consumption of labour-intensive resources by the first human inhabitants of 
Sahul. 
 
• Despite its potential, the paragraph describing the groundstone assemblage in the main text, 
including use-wear and residue analyses, adds little to the overall discussion. It is not clear how the 
presented evidence is related to the macrobotanical assemblage. The authors merely state that at 
least 8 out of 29 tools were used for plant processing, including seed-grinding (n=2) and pounding 
(n=1). If the authors wish to establish a direct correlation between the use of the grinding stones and 
the consumption of labour-intensive plant resources, as seems to be the case, more clear evidence 
needs to be presented. In particular, starch grain analysis has the potential to provide direct evidence 
of the processing of USOs, nuts and seeds. According to SI Section 4, high densities of starch grains 
were encountered in at least two grinding stones. Have these starch grains been identified? Were 
Buchanania sp., Canarium australianum, Curcuma australasica, Pandanus spiralis and Persoonia 
falcata included in the modern starch reference collection? Have starch grains from these taxa been 
identified in the grinding stones from Madjedbebe? If this research is still ongoing and/or the authors 
do not wish to present it here they may reconsider establishing a direct correlation between the 
groundstone assemblage and the consumption of labour-intensive plant resources until more 
conclusive evidence is available. 
 
Juan José García-Granero 
 
References 
 
• Allen, J. 2017. Yes, Virginia, there is a Santa Claus; He just doesn’t bring presents to children who 
don’t believe in him. Australian Archaeology 83:163–165. 
• Clarkson, C., et al. 2017. Human occupation of northern Australia by 65,000 years ago. Nature 
547:306–310. 
• Clarkson, C. et al. 2018. Reply to comments on Clarkson et al. (2017) ‘Human occupation of 
northern Australia by 65,000 years ago’. Australian Archaeology 84:84–89. 
• O’Connell, J.F. e al. 2018. When did Homo sapiens first reach Southeast Asia and Sahul?. 
Proceedings of the National Academy of Sciences 115:8482–8490. 

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