Hey guys, get a grip. The fact is 99.99% of all creatures, mammals or otherwise, that have ever inhabited this pale blue dot in the universe are extinct. And the remaining species, with the possible exceptions of alligators and hair lice, will become extinct at some point in the future. And, I would submit that the villain in all the previous extinctions was Mother Nature, as opposed to the evil, climate changing, human race.
Also how do they know that this rat never hitched a ride somewhere else and set up another home?
“...with the possible exceptions of alligators and hair lice...”
Cockroaches and houseflies are here for the duration.