Back to the matter of felines.
An interesting phenomena that I have come across is that of the Australian Panther. For a long time now there have been sightings of large black panthers in parts of NSW and Victoria, they are usually ignored as nonsense, I myself thought it to be ludicrous. However, there does appear to be evidence that some kind of large black cat does exist in the area and it not just being an isolated case. There is not much information on this in the scientific world, most comes from citizens and cryptozoologists(lunatics in other words, one attributed this to being a Marsupial Lion that he claims must still exist) so bear this in mind(it's a shame I think it really should be investigated).
First of we have the eyewitness sightings, well that is a start but on their own they don't mean much, then we have the reports and footage of dead livestock. There are reports of the bodies of the dead animals being kept in trees as cats do and there are reports and images of animals being killed in a similar manner to how large cats kill, the mouth is bloodied or the throat is ripped out. Large cats tend to either target the throat or bite the snout of an animal to suffocate it, this still does not prove it however, it's not impossible that a dog could have done it and just killed in an unusual way in a few isolated incidents, one or two bodies is not proof. Lastly we have video evidence. These are certainly of some large cats. But are they panthers? Maybe not they could be feral cats that are growing to large proportions, but these are really quite large indeed. However, Australia has no proper Apex predator, yes by definition almost any ecosystem has an apex predator but we lack a creature on the scale of a true apex predator like a tiger or leopard, we lack even a lynx, therefore it is likely that feral cats would eventually specialise and some would become large cats to fill this niche, but this is a process that would take thousands of years.
https://youtube.com/watch?v=MwXbLaw3xtc
https://youtube.com/watch?v=hdzNdYjqt2s