Specific Mars Colony Development & Planning

[Robotbeat]

There are birth defects that are increased in prevalence at high altitudes on Earth (http://onlinelibrary.wiley.com/doi/10.1002/(SICI)1096-8628(19990903)86:1%3C9::AID-AJMG3%3E3.0.CO;2-X/abstract). Yet tens of millions of people live at very high altitudes in places like South America and Tibet. And the people living at high altitude have even developed biological, evolutionarily-driven genetic adaptations to the conditions there: https://en.wikipedia.org/wiki/High-altitude_adaptation_in_humans

It is very unhealthy to live at very high altitudes for most of the human population. Birth defects, birth weight reduction, and pregnancy complications like preclampsia can even be caused. But over time, multiple populations of humans have developed adaptions to these conditions and women from populations who have lived at high altitudes for thousands of years are able to avoid these problems and give birth to normal weight babies at high altitudes.

I do not expect life to be different for colonists on Mars. Hypogravity may or may not have serious health consequences, but life is not a static thing. Organisms (including humans) adapt to the environment in which they live. Evolution is the slowest method of adaption (Tibetans adapted in less than 3000 years), but provided a minimum level of viability is maintained (even artificially through interventions), it can be counted on.

[guckyfan]

I agree with your overall point that future developments could overcome almost any difficulty, but that doesn't help with the discussion of what we could do now. This thread is pointless if the answer to any question is we'll figure it out in the future.

True but we need to avoid both extremes.

1 not handwave away any problem by saying we will solve them in the future.

2 not argue that we have not done that yet so it is a showstopper. Most problems are not, they are to be solved.

[Eric Hedman]

Here is an article about the Visual impairment intracranial pressure syndrome (VIIP) suffered by 80 percent of ISS crew members.  It will be interesting to find out how many of these types of problems will exist on Mars: https://www.washingtonpost.com/national/health-science/the-mysterious-syndrome-impairing-astronauts-eyesight/2016/07/09/f20fb9a6-41f1-11e6-88d0-6adee48be8bc_story.html

[JulesVerneATV]

people have often talked of the small in size moss, non-vascular flowerless plants  as a supports in a new Mars eco system for some of the plants and animals inside the early Mars domes and biospheres

The Moss That Survived Nine Months in Space
https://www.universetoday.com/articles/the-moss-that-survived-nine-months-in-space
Moss spores spent nine months strapped to the outside of the International Space Station, exposed to vacuum, cosmic radiation, temperature swings from minus 196°C to 55°C, and unfiltered solar ultraviolet light. Over 80 percent survived the ordeal and returned to Earth still capable of growing into new moss plants.

Moss spores withstand long term exposure outside space station
https://www.spacedaily.com/reports/Moss_spores_withstand_long_term_exposure_outside_space_station_999.html

[Vultur]

people have often talked of the small in size moss, non-vascular flowerless plants  as a supports in a new Mars eco system for some of the plants and animals inside the early Mars domes and biospheres

The Moss That Survived Nine Months in Space
https://www.universetoday.com/articles/the-moss-that-survived-nine-months-in-space
Moss spores spent nine months strapped to the outside of the International Space Station, exposed to vacuum, cosmic radiation, temperature swings from minus 196°C to 55°C, and unfiltered solar ultraviolet light. Over 80 percent survived the ordeal and returned to Earth still capable of growing into new moss plants.

Moss spores withstand long term exposure outside space station
https://www.spacedaily.com/reports/Moss_spores_withstand_long_term_exposure_outside_space_station_999.html

Survival as spores is honestly not terribly special, a lot of simple life forms can survive pretty extreme conditions in spore/endospore/scambiotic/anhydrobiotic state. There's a fly larva that can survive being dipped in liquid nitrogen.

The tricky part would be actively growing and metabolizing under Mars conditions. Some lichen can apparently do this, but vascular plants cannot (they need oxygen in the ambient atmosphere, since there's no "circulation" to get oxygen produced in the leaves to the roots). I am not sure where mosses fall on that scale.

[Vultur]

people have often talked of the small in size moss, non-vascular flowerless plants  as a supports in a new Mars eco system for some of the plants and animals inside the early Mars domes and biospheres

The Moss That Survived Nine Months in Space
https://www.universetoday.com/articles/the-moss-that-survived-nine-months-in-space
Moss spores spent nine months strapped to the outside of the International Space Station, exposed to vacuum, cosmic radiation, temperature swings from minus 196°C to 55°C, and unfiltered solar ultraviolet light. Over 80 percent survived the ordeal and returned to Earth still capable of growing into new moss plants.

Moss spores withstand long term exposure outside space station
https://www.spacedaily.com/reports/Moss_spores_withstand_long_term_exposure_outside_space_station_999.html

Survival as spores is honestly not terribly special, a lot of simple life forms can survive pretty extreme conditions in spore/endospore/scambiotic/anhydrobiotic state. There's a fly larva that can survive being dipped in liquid nitrogen.

The tricky part would be actively growing and metabolizing under Mars conditions. Some lichen can apparently do this, but vascular plants cannot (they need oxygen in the ambient atmosphere, since there's no "circulation" to get oxygen produced in the leaves to the roots). I am not sure where mosses fall on that scale.

.
On further research: an experiment like this has been done in simulated Martian conditions with a different moss species (Syntrichia caninervis, here's the paper: https://www.cell.com/the-innovation/fulltext/S2666-6758(24)00095-X ) but like the ISS moss experiment (which used Physcomitrium patens, here's the paper: https://www.cell.com/iscience/fulltext/S2589-0042(25)02088-7) the moss survived *dormancy* in Mars conditions, it didn't actively grow in those conditions. (Though it looks like the simulated Mars experiment used whole plants, not spores like the ISS one. That is more notable IMO; spores and other similar forms, like bacterial endospores, can often survive all sorts of insane conditions.).

In contrast, a couple of lichen species have been shown to *actively photosynthesize and metabolize* in simulated Mars atmosphere conditions, not just passively survive while dormant. Here's one of the papers: https://www.nature.com/articles/s41598-023-32008-6 (this one is Xanthoria parietina at "a 95% CO2 atmosphere at 600 Pa,").