Updated Sep 27
The problem would be the likely combination.
If the rest of humanity were wiped out, in a plague, an asteroid strike, a zombie apocalypse, or a nuclear war, the Earth would be inherited by microbes, cockroaches, Keith Richards, and me.
We probably wouldn’t be a very attractive or healthy-living couple, and I shudder to think of our potential offspring. And I’d be more interested in the microbes.