So we've a sudden appereance of a type followed by such tiny amounts of change that it is impossible for the scientits to tell whether modern voles are a new species, or just a subtype of the voles of 1 million years ago.
This rate of change is woefully inadequate to explain the fossil record. There have probably been over one million new FAMILIES of creatures appear since the first wave of animals arrived in the Cambrian Explosion. That is one new FAMILY every 435 years. This article is another example of my contention that evolution, to the extent it happens, does not happen fast enough or cause change enough to explain the fossil record.
Ten layers got studied. The oldest layer has some variation already. Are you assuming the oldest layer studied is a "sudden appearance?" Why?
I see no "sudden appearance" in this article.
This study seems to have been modeled on Gingerich's survey of Pelycodus, which also showed gradual change accumulating steadily.
