Care Bears

Tardigrades, aka "water bears", are one of my inspirations for how we will adapt our future generations to live on Mars.  Humans in our current state can't do it, and even though we have some terrestrial superpowered human genes (for instance, Tibetan sherpas are adapted to ferociously cold, low pressure and low oxygen environments) we still couldn't do it.

But tardigrades can survive in space.  Even more amazingly, they can reproduce in space.  You might assume that a cave on Mars would be a picnic compared to open space, so might we find them there?  But tardigrades live on moss and lichens - they have to have something to feed on.  A cave on Mars would probably need to house, protect and feed complex colonies of plants and animals in order to harbor an organism like a tardigrade.

It's entirely possible that there are colonies of lichens, bacteria or other organisms (which may be far outside our experience, or ALIEN) that tardigrades or a cousin species of tardigrades could live on.

If we find a species adapted to Mars to pull DNA from, potentially we've got some ideal genes for a human-Martian edit.  I imagine that they would fair better if they were much smaller than us.  Mars gravity is 1/3 of Earth's, so humans on Mars might be weaker and less vigorous if they were oversized for the conditions.

On another note, Mars, without the blanket of radiation reflecting atmo we have on Earth, would be a blast zone for solar radiation and all manner of space weather effects, so Marsers (do NOT call them Martians, they would be very offended by that) would have to have genetic adaptations that enabled them to cope with that much radiation.  Again, DNA from those lovable water bears might come in very handy.

Tardigrades can form glass around cell walls to cope with extreme dehydration, they can party in open space and they shed their skins, which to me seems like a brilliant way to consolidate cell turnover to slough radiation toxicity from the body.  Elephants get much less cancer than we do, because their cells die more frequently.  Doctors tell us to exercise to help prevent illness, one of the reasons being the benefits of accelerated cell turnover.

I believe Marsers will need genetic adaptations beyond the human gene pool, and water bears look like they've got at least some of the right stuff.

They're also kinda cute.  In an I-am-so-glad-you-are-microscopic-and-not-eight-feet-high kinda way...