>>What does this mean?
It means that individual sinners sinned. Their sin does not rub off on you or me, just as our sins do not rub off on them. Pray for them just as pray for ourselves. But you can worry about that issue if you choose. I choose not to.
What impact does the perversion of nature have upon the fitness of species/cultures?
Romans Chapter 1 describes a cultural cycle.
"because of this, God gave them over"
Because of what?
Gave them over to what?