As others have said, I found it surprising that the change in rate with time scale compared was surprising. Simon Ho's paper is downloadable (link in OA) and it has a mathematical framework for his discussion. I'm not sure if the argument is accessible to non-specialists but I'll have a read.

Rabbit hole warning: Björn Kurtén the Finnish paleontologist whose work on horse fossils was cited early in the OA turns out to be a very interesting character. He wrote what he described as a 'paleonovel' about encounters between CroMagnon and Neandertal people...