A new paper on pre-european contact between Polynesians and Native Americans is out today in Nature. I rarely do this on Twitter but regarding this is my area of expertise, I need to say something about how problematic this article is: https://www.nature.com/articles/d41586-020-02055-4?fbclid=IwAR1k5Kl55852sXvLVK8v59mWbpNRvvtPBHnmVRQshc61nEuf4Z8-8y-JQQc#ref-CR1

It based on modern genome analysis of individuals on today’s French Polynesia, Cook Is. and Rapa Nui. ADMIXTURE analyses show that many islanders appear to have a European component from colonial admixture, but also detect admixture in eastern Polynesia from Native American ind.

Authors explained that this admixture did not happen on Rapa Nui but likely on other Polynesian islands in the West.

Dating this contact event between AD1150 and 1230, they suggest that contact and admixture happened during Polynesian expansion in the region when they arrived on islands (Marquesas) already inhabited by Native Americans.

Problem 1: complete lack of engagement from the geneticists authors with the abundant archaeological and anthropological literature on the topic and contexts, not even to the key-synthesis by @MatisooSmith and colleagues in 2011 which discussed many lines of evidence.

The only reference cited is Heyerdahl which thesis has long been dismissed. Before dropping big news such as these with big implications, there NEED to be cross-disciplinary engagement and more discussions! A point that should also in my view be made during the peer-review.

Proposing that Polynesians discovered islands already inhabited 1/ dismisses all archaeological evidence gathered for 70 years, 2/ suggests that they wouldn’t have been able to sail themselves to South America despite their incredible navigating abilities, and...

3/ presents a high risk of resurgence of old, and often racist, ideas about the history of the region.

Problem 2: no context nor information on the 1980s sampling process on Polynesian populations who by that time were not required to give their consent. Let’s not forget that people who gave their blood samples have family and personal trajectories that matter.

The dating model implies that these admixtures are not modern. I have concerns about the dating process that leads to such a narrow chronological range, coincidentally fitting well with Wilmshurst et al. model (2011).

While we see a demographic expansion in the region at that time, we also have more and more evidence of human presence on the island two to three centuries earlier.

Other problems exist here, but I will only kindly suggest to pay attention to the real names of the islands you describe: Palliser Is. in the Tuamotu is the colonial term referring to the northwestern group of atolls around Rangiroa. Please use the indigenous name of the place.