Unfortunately the research efforts were misdirected as they only looked at one aspect of the ability of an isolated Nimba tribe in Nambia, South Africa; the ability to recognise emotional expressions.
The outcomes of that study were then used to challenge Paul Ekman’s findings that emotions are universally expressed. There have been over 75 studies that have demonstrated that these very same facial expressions are produced when emotions are elicited spontaneously (Matsumoto, Keltner, Shiota, Frank, & O’Sullivan, 2008).
Ironically this was published in the Handbook of Emotions in p215 (2008) – edited by Lisa Feldman Barrett et al. This is a serious disconnect that good research should have addressed.
This seems to have been supported by the rejection of the Nambia study by the respected journal, Science. Barrett reported in July 2013 to Shannon Fischer, in a Boston Magazine interview that “Clearly people don’t give a shit about data, because if they did, I wouldn’t have this battle on my hands.” Maybe the data needs to connect with more relevance to the claims made.