The Insane Biological Cost of Living on Mars - Scott Solomon - #1065

What’s the NASA CHAPEA experiment that just crossed one hundred days?

It’s a Mars-life simulator at Johnson Space Center, a 3D‑printed habitat with a crew of four living like settlers for a full year; it’s the second long mission of its kind, designed to learn how real habitation might work.

Are they studying bodies or minds more?

Mostly minds, because they can’t mimic Martian gravity or radiation on Earth, but they can recreate confinement, limited supplies, and group dynamics.

It’s like the slowest reality show ever; do these analog sites actually help?

They do; I visited the Mars Desert Research Station in Utah and saw how crews stress‑test daily life and learn what breaks in realistic settings.

Big picture, is space settlement more technological or evolutionary?

As an evolutionary biologist, I think if people live and raise families off‑world for generations, evolution is unavoidable.

Island evolution proves it, right—like the tiny hominins from Flores?

Yes; island isolation often changes body size, and Flores had small hominins alongside giant reptiles, with a similar small-bodied cousin later found in the Philippines; the Flores species likely vanished around fifty thousand years ago, overlapping with early Homo sapiens.

So if we settle Mars, we’re choosing divergence on purpose.

Exactly; this would be our first deliberate move into an environment so extreme that lasting biological change is expected.

What does spaceflight do to the body before we even land?

Microgravity weakens muscles and bones, shifts fluids to the head, and often leads to anemia; in low Earth orbit Earth’s magnetic field reduces radiation, but beyond it exposure rises, cognitive speed can dip, and the unknowns stack up—those Van Allen belts were found when early sensors maxed out from intense radiation.

We arrive on Mars—what then?

After six to nine months deconditioned, even one‑third gravity is a shock; exercise helps but not fully, vision can change, and food variety is a serious hurdle, which is why growing fresh produce becomes mission‑critical.

Higher radiation means more mutations; does that speed adaptation in a good way?

It speeds evolution but in a brutal way—more errors, more illness, and natural selection doing its work through suffering.

Small founding groups, Seveneves vibes—plus island‑like habitats; who thrives psychologically?

Founder effects will loom large, so choose diverse crews with complementary skills and strong teamwork; odd numbers help avoid stalemates, and open, steady communicators are more likely to succeed.

Who should govern Mars—Earth, companies, or colonists?

Leaders on‑site, not directed from Earth; minutes‑long delays make live governance impossible, so legitimacy and accountability have to live where the decisions do.

What does isolation do to the mind, and what about that view‑from‑space epiphany?

Knowing you cannot leave is taxing, so build in mental‑health support; yet many feel a powerful shift seeing Earth from space, though Mars‑born kids likely won’t share that bond, much like later‑generation immigrants.

We may live underground with no real nature; that seems psychologically heavy.

Subsurface living shields from radiation and meteors, but life under artificial light without wildlife could reshape vision, mood, and our sense of place.

Reproduction is the big unknown—has anyone even had sex in space?

Human reproduction in space is largely untested; some animal studies exist, but we lack solid data on conception through child development in low gravity and high radiation, and there’s no verified record of sex in space.

Could tech‑mediated birth help, or create new problems?

Mars‑born people may have lower bone density, making childbirth risky from pelvic fractures; defaulting to C‑sections could relax a key constraint and drift toward larger babies, creating new medical and evolutionary issues, so we need careful studies in orbit first.

How fast could Martian humans become separate, and what blocks back‑and‑forth travel?

Limited gene flow speeds divergence, and two big barriers will be gravity‑adapted bodies and nonoverlapping immune training; Mars microbiomes will evolve away from Earth’s, making quarantine the norm and accelerating speciation.

Culture will be forged in scarcity and danger; that feeds biology too, right?

Yes; rapid cultural shifts in isolated, high‑stakes settings will loop back into selection pressures, tightening the divergence.

Ethically, is it right to have kids there, and would genetic engineering be justified?

On Mars, engineering traits for radiation or gravity tolerance might be the least harmful path for future children, but it could also lock them away from Earth forever; the ethics are different when escape from risk is not an option.

So, should we go now or wait?

Becoming multi‑planetary likely matters in the long run, but we should not rush settlements before we’ve answered core life‑science questions—especially reproduction—while tech keeps advancing.

Scott Solomon, this was brilliant; where can people find your work?

My book Becoming Martian is out from MIT Press, there’s a CuriosityStream series by the same name, and my podcast Wild World digs into fieldwork here on Earth.

If you want more great reads, grab my Modern Wisdom reading list at chriswillx.com slash books; it is free and curated to be fun and useful.