Link to original paper which is still a non-peer reviewed biorxiv article [0]. The crux of the paper is based on expressions of plasticity correlating with the

Link to original paper which is still a non-peer reviewed biorxiv article [0]. The crux of the paper is based on expressions of plasticity correlating with the percentage of sleep time spent in REM (fig.2). Apart from the high-level questions raised already in the comments there are several caveats in the data: Data points are sparse i.e. the number of samples included are too few to strongly believe in correlations. Taking out extreme data points would make the correlations look independent. The data values across 25 primate species are based on averages across previous studies and using proxies where some data was not available. I do not know how justifiable such approaches are but I am skeptical about them. [0] https://www.biorxiv.org/content/10.1101/2020.07.24.219089v1.full.pdf https://www.biorxiv.org/content/10.1101/2020.07.24.219089v1....