Based on the excellent documentary series "Star Trek" I think it's safe to assume there are species that would colonize the galaxy.

But on a more serious note. You make an interesting point. Our entire history has been a fight for survival against a merciless environment (and other species). It's a core part of our DNA to colonize, grow, and thrive.

But assuming that is representative of what all life would go through may not be safe. It's hard for me to imagine how evolution would create life without the threat of killing off bad mutations, but that doesn't make it impossible. Definitely good to keep an open mind.

Our history has been a fight to survive and thrive where it's been possible to survive and thrive within the environment of our own ecosystem. Despite some exploration, we haven't exactly built cities in Antarctica or the ocean floor, because we can't thrive there. Whatever drive to colonize and grow that might exist in our DNA doesn't extend into space. There's no natural evolutionary path into space - it's unimaginably vast, it costs a ludicrous amount of effort and energy expenditure just to reach orbit, and once you're there literally every aspect of it is hostile to life, and every step is exponentially more expensive and deadly.

I can imagine a species with the same drives as ours, but which doesn't advance beyond colonizing its own solar system, or sending probes to nearby stars, because I can imagine that happening with us. I suspect that, as far as space exploration (much less long term colonization) goes, politics, economics and culture matter far more than our innate drive to find whatever's over the next mountain. We had the capability for manned lunar landings, but didn't follow up with moon-bases or a colony on Mars because that initial drive was fueled by competition and fear between superpowers. We gave up that capability because there was nothing interesting on the moon, and the public stopped caring, and anything but probes started to seem like a boondoggle.

And we're lucky enough to have a moon and a couple of nearby planets to keep us curious. How many technologically advanced but "landlocked" civilizations might there be, who don't venture into space because there's nothing to even theoretically colonize for hundreds, if not thousands, of light years?

Of course, if we had warp drives, things would be different. But the Fermi Paradox suggests that such things are either not possible, or somehow not reliable over the long term, possibly due to energy requirements or something.

Very interesting indeed, and that makes a lot of sense. I wonder if the Elon Musk style reasons would kick in (such as Earth is no longer hospitable to us because AI has completely taken over), which would definitely change the fact that Earth is a thriving environment for us. But short of that, I could definitely see you being right.