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Why don't we send tardigrades and other extremophiles into space to colonize possible life-sustaining planets and moons?

by jsbg 2y ago

deleted 2y ago
[deleted]
pram 2y ago
I think the general idea is not to contaminate planets with possible life so we can eventually study what completely different evolution circumstances produces.
- andsoitis 2y ago
  > I think the general idea is not to contaminate planets with possible life so we can eventually study what completely different evolution circumstances produces. History suggests that is not what will happen when we find a planet that harbors life sustaining conditions, even if our presence would destroy all life on it. Homo sapiens' track record is one of self-interest and the (largely-ish, though sadly not mostly) unintentional devastation of life forms in human vicinity. But I digress. When we discover a world with livable conditions, we will occupy it, fill the pace, mine it, etc. Native life on it will come under selective pressure. And that's not necessarily a bad thing.
- mc32 2y ago
  Do you think we’d put information gathering over survival? I don’t think so. I’m not sure a successful species would.
- thanatos519 2y ago
  Yes that's the idea and I think it is stupid. We should be spreading DNA far and wide instead of sending humans. As much as I am curious about evolution, I am more interested in a deep future full of life.
  - euroderf 2y ago
    Fungi have you covered.
AnotherGoodName 2y ago
They can go dormant in extreme conditions they can’t thrive in such conditions. It’s a bit of a myth with these. They need similar conditions to multiply as all other life. If you put them temporarily in an extreme condition they can go dormant and come back when conditions are better. FWIW we trade so much material with outer space (super volcanos etc) that if life could colonize space that easily it would have done so billions of years ago.
- joshdavham 2y ago
  This brings up an interesting question though. Could we create a minimially viable living environment for these extremophiles to survive on other planets? For humans, we'd need pretty incredible technology to sustain life on mars, but for tardigrades, they could probably survive with a lot less.
  - kombookcha 2y ago
    There's surviving, and there's thriving - tardigrades could probably hang out in a Mars crater for a long time, but what they'd need to sustainably live on an alien planet is something to eat during the periods where conditions are right for them to thaw out. If there's nothing for them to wake up to, they won't be making anymore tardigrades. Say, a very hardy algae that could make it in some suitable microbiome - like humid cracks in the rocks, or a fungus that could hang out in underground caverns shielded from UV radiation. If we are trying to seed a place with life where we can't reliably go ourselves, it seems important that the 'colony' should become self-sustaining immediately-ish. (Also I find the idea of launching swarms of micro-pods loaded up with hardy, tiny lifeforms endearing - like throwing seed bombs over a tall fence :) )
    - pvaldes 2y ago
      And like that naive seed-bombs trend, they would do more harm that good.
deleted 2y ago
[deleted]
ljlolel 2y ago
What makes you think our ancestors haven’t?
librasteve 2y ago
https://www.nasa.gov/general/swarming-proxima-centauri/ https://www.nasa.gov/general/swarming-proxima-centauri/
solardev 2y ago
What would they eat? Tardigrades on earth, for example, eat plants, bacteria, other tardigrades, etc. But all of those require functioning ecosystems (even extreme ones). If you put a bunch of tardigrades (or anything) on a planet without a suitable ecosystem, they'll all just die or stay dormant (in the case of tardigrades). You gotta terraform the heck out of it first. On our planet we try to measure something called net primary productivity (https://en.wikipedia.org/wiki/Primary_production?wprov=sfla1 https://en.wikipedia.org/wiki/Primary_production?wprov=sfla1), which is basically a measure of how much energy can be made useful to lifeforms in a planet's food web. There are only a few processes we know of that can do this, such as plants and algae and other photosynthetic organisms turning sunlight into edible organic substances for other consumers to eat. Tube worms chemosynthesizing from ocean floor hot spring vents is another one. These species are called autotrophs ("self feeders") and they constitute the basis of the entire food web on Earth, as far as we know. https://en.wikipedia.org/wiki/Autotroph?wprov=sfla1 https://en.wikipedia.org/wiki/Autotroph?wprov=sfla1 Without a suitable ecosystem for autotrophs, there isn't enough biologically available energy for the heterotroph species (everything else, us included, that eats other species to survive). So as far as know, a planet has to have a suitable environment for autotrophy to evolve first (or for alien life to arrive on, eg through exobiogenesis). You can't just send a bunch of consumers there and expect much to happen. At most they'd eat each other and then all become extirpated (locally extinct). Sci fi of course has us terraforming planets to make them (Earth) life sustaining, but that usually starts with plants and algae and such too before introducing the heterotrophs and inevitable monsters.

Why don't we send tardigrades and other extremophiles into space to colonize possible life-sustaining planets and moons?

by jsbg 2y ago

Why don't we send tardigrades and other extremophiles into space to colonize possible life-sustaining planets and moons?

deleted 2y ago

[deleted]

pram 2y ago

I think the general idea is not to contaminate planets with possible life so we can eventually study what completely different evolution circumstances produces.

andsoitis 2y ago
> I think the general idea is not to contaminate planets with possible life so we can eventually study what completely different evolution circumstances produces. History suggests that is not what will happen when we find a planet that harbors life sustaining conditions, even if our presence would destroy all life on it. Homo sapiens' track record is one of self-interest and the (largely-ish, though sadly not mostly) unintentional devastation of life forms in human vicinity. But I digress. When we discover a world with livable conditions, we will occupy it, fill the pace, mine it, etc. Native life on it will come under selective pressure. And that's not necessarily a bad thing.
mc32 2y ago
Do you think we’d put information gathering over survival? I don’t think so. I’m not sure a successful species would.
thanatos519 2y ago
Yes that's the idea and I think it is stupid. We should be spreading DNA far and wide instead of sending humans. As much as I am curious about evolution, I am more interested in a deep future full of life.
- euroderf 2y ago
  Fungi have you covered.

AnotherGoodName 2y ago

They can go dormant in extreme conditions they can’t thrive in such conditions. It’s a bit of a myth with these. They need similar conditions to multiply as all other life. If you put them temporarily in an extreme condition they can go dormant and come back when conditions are better. FWIW we trade so much material with outer space (super volcanos etc) that if life could colonize space that easily it would have done so billions of years ago.

joshdavham 2y ago
This brings up an interesting question though. Could we create a minimially viable living environment for these extremophiles to survive on other planets? For humans, we'd need pretty incredible technology to sustain life on mars, but for tardigrades, they could probably survive with a lot less.
- kombookcha 2y ago
  There's surviving, and there's thriving - tardigrades could probably hang out in a Mars crater for a long time, but what they'd need to sustainably live on an alien planet is something to eat during the periods where conditions are right for them to thaw out. If there's nothing for them to wake up to, they won't be making anymore tardigrades. Say, a very hardy algae that could make it in some suitable microbiome - like humid cracks in the rocks, or a fungus that could hang out in underground caverns shielded from UV radiation. If we are trying to seed a place with life where we can't reliably go ourselves, it seems important that the 'colony' should become self-sustaining immediately-ish. (Also I find the idea of launching swarms of micro-pods loaded up with hardy, tiny lifeforms endearing - like throwing seed bombs over a tall fence :) )
  - pvaldes 2y ago
    And like that naive seed-bombs trend, they would do more harm that good.

deleted 2y ago

[deleted]

ljlolel 2y ago

What makes you think our ancestors haven’t?

librasteve 2y ago

https://www.nasa.gov/general/swarming-proxima-centauri/ https://www.nasa.gov/general/swarming-proxima-centauri/

solardev 2y ago

What would they eat? Tardigrades on earth, for example, eat plants, bacteria, other tardigrades, etc. But all of those require functioning ecosystems (even extreme ones). If you put a bunch of tardigrades (or anything) on a planet without a suitable ecosystem, they'll all just die or stay dormant (in the case of tardigrades). You gotta terraform the heck out of it first. On our planet we try to measure something called net primary productivity (https://en.wikipedia.org/wiki/Primary_production?wprov=sfla1 https://en.wikipedia.org/wiki/Primary_production?wprov=sfla1), which is basically a measure of how much energy can be made useful to lifeforms in a planet's food web. There are only a few processes we know of that can do this, such as plants and algae and other photosynthetic organisms turning sunlight into edible organic substances for other consumers to eat. Tube worms chemosynthesizing from ocean floor hot spring vents is another one. These species are called autotrophs ("self feeders") and they constitute the basis of the entire food web on Earth, as far as we know. https://en.wikipedia.org/wiki/Autotroph?wprov=sfla1 https://en.wikipedia.org/wiki/Autotroph?wprov=sfla1 Without a suitable ecosystem for autotrophs, there isn't enough biologically available energy for the heterotroph species (everything else, us included, that eats other species to survive). So as far as know, a planet has to have a suitable environment for autotrophy to evolve first (or for alien life to arrive on, eg through exobiogenesis). You can't just send a bunch of consumers there and expect much to happen. At most they'd eat each other and then all become extirpated (locally extinct). Sci fi of course has us terraforming planets to make them (Earth) life sustaining, but that usually starts with plants and algae and such too before introducing the heterotrophs and inevitable monsters.