> We should be wary of bringing Martian microbes back to Earth, because they may find our environment too hospitable and end up invasive species.

They could even already have invaded in the past, and we descended of them[1]. Earth as Mars ancient lifeboat[2].

[1] https://www.bbc.com/news/science-environment-23872765

[2] https://badspacecomics.com/apostles-of-mercy