Introduction

In October of 2022 I emailed 4 different professors who had published similar kinds of research to weigh in on the legitimacy of the Wade et al. 2022 study, Post-Pleistocene Horses (Equus) from México:

Bruce J. MacFadden, PhD, Distinguished Professor, Florida Museum of Natural and Director at the University of Florida Thompson Earth Systems Institute (TESI)
[Name withheld] - [A highly prestigious and well-known institution]
Nawa Sugiyama - No response
William Fash - No response

Responses

I received 2 responses. One of them granted me permission to publish their response. The other asked me to not post their response (at least verbatim) since their institution must clear any official quotes.

Professor MacFadden Response

I looked over this paper and the data and conclusions drawn from this study seem interesting and authoritative. It challenges prevailing dates for the extinction of Equus in southern N America.

Name withheld

One other professor responded with a fairly lengthy response, but their institution has a strict policy about clearing any response that might result in “official quotes.” Although they were an expert in the topic area generally and had studied the specific topic as a student, they did not feel well versed in the specific area and time periods to be super confident in their response and they encouraged me to seek out other people with more expertise in the relevant geographical area and time period. They noted that the paper did not included detailed methods about radiocarbon dating and mentioned that pretreatment methods can affect how radiocarbon dates turn out, by thousands of years even. They encouraged me to inquire about the particular methods used and how that might impact the outcome of the study. They did not indicated any more than that whether they did or did not have confidence in the study.

Results and Conclusion

One professor seemed to regard the paper as legitimate, but they gave no detailed feedback. The other (whose name has been withheld by request due to institutional policy) pointed out one potential weakness in the paper and encouraged me to seek additional experts. Their response was not valenced in any particular orientation toward the paper, however, from what I could tell.

Take together, this validation exercise points very tentatively towards the legitimacy of the study but also suggests that further review could be useful and could potentially demonstrate weakness in the 14C dating technique.

Appendix: Template request for validation

The template of my request was this:

Dear <Title and Name>:

I am very interested (as an amateur) in competing theories about the existence of horses on the American continent in pre-Columbian times, but I’m not a geologist or archaeologist. Recently, a paper was published suggesting that horses existed in the Americas much later than is the general consensus, as I understand it:

POST-PLEISTOCENE HORSES (EQUUS) FROM MÉXICO

I am interested in expert assessment of the robustness of the study/paper. I’m not exactly sure what questions I should be asking, but these seem like a reasonable starting point:

I sent this to you because you seem from my vantage point to be qualified to speak to this topic, but I should ask if you feel academically qualified to speak to the robustness of this study (i.e., does it fall within the scope of your expertise)? If there might be someone even more qualified than yourself, would you mind giving me their name so that I could also contact them?
Do you consider the analysis presented in the above linked paper robust?
Are there analyses that could have been done that probably should have been done for this study? (i.e., what might be missing?)
Do you feel that this paper definitively demonstrates that horses existed during the time frames the authors indicate?
In your opinion, does this study overturn (or will this study overturn) the existing consensus that horses did not exist in the Americas during this time frame? If not, what would you need to see before accepting that the current consensus had been overturned?

What else can you tell me about a study like this that I might not appreciate prima facie?

For reference, the nearest similar study I can find on this topic so far is this one from 2019.

Thank you so much for your time.

Sincerely,

<bwv549>, PhD