There are a few ways that one could reason from absence of evidence to evidence of absence, and that has a lot to do with what other kinds of fossils (if any) w

There are a few ways that one could reason from absence of evidence to evidence of absence, and that has a lot to do with what other kinds of fossils (if any) we've found in the same area in the same period. One possibility is that cats found themselves in relatively dry areas where their remains would be picked apart by scavengers long before any fossilization could take place. The article mentions that forests turned into savannas at the time. On a less serious note, perhaps the cat gap occurred when cats temporarily lost their skeletons and became fully liquid, or at least cartilaginous like sharks. Don't we all know how flexible they are? :)