Evolution into Space

[Luminal]

Life has a long history of conquering new environments, from the ocean into freshwater bodies, from water to land, and from land to air (and some cases of water to air). It has also adapted to and even flourished in the most extreme environments on Earth, from Antarctica to the Sahara Desert to subterranean habitats miles under the surface. I suppose life has one place left to go: space. And through space, the untapped and virtually unlimited energy and resources that abound in our Solar System and beyond.

 

We already know that at least one species has evolved to enter, and even partially inhabit, space. This was done by way of the evolution of larger brains, leading to greater tool use. Eventually, the tools of this species (homo sapiens) enabled it to traverse into this new environment.

 

Barring the evolution of intelligence and use of tools, do you think it is possible that life could evolve into space, and eventually spread to other planets?

 

I ask this because it could have major ramifications on life in the Universe. If even one species has evolved to survive in and traverse through great distances of space, then there would be little to prevent it's spread throughout the cosmos.

 

Of course, even providing several times longer than life has existed on Earth, no such species would have gotten very far. At most, perhaps it could have come to fill it's home galaxy with life. The distances between galaxies themselves are simply too great to overcome (not to mention the Universe hasn't been around long enough for such a passage to take place).

 

Yet, it's feasible, in my opinion, that life could spread throughout it's own solar system at least. To do so, it would require some form protection from its star's radiation as well as the vacuum of space. I believe there are pre-adaptations on Earth already, such as an arthropod's exoskeleton, that could be the basis for such an system to survive the harsh conditions in space.

 

Thoughts?

[CDarwin]

It would either need something to eat, too, and oxygen (or some stand-in) and water with which to metabolize it, or carbon dioxide for photosynthesis. Those might be the biggest limiting factors. Calories are few and far between among the stars.

[Luminal]

It would either need something to eat, too, and oxygen (or some stand-in) and water with which to metabolize it, or carbon dioxide for photosynthesis. Those might be the biggest limiting factors. Calories are few and far between among the stars.

 

There are several examples of organisms going into long-term stasis with hardly any metabolism. In fact, I once witnessed a cockroach die in a dark corner of my apartment (a crack between two cabinets which I couldn't reach), and it "awoke" over 12 months later. One day, I noticed it's legs twitching, and within a few minutes it flipped over and ran off.

 

As to why natural selection would favor such a evolutionary pathway, I can think of at least one compelling reason: predation. A species of a flying insects or birds might adapt to flying higher and higher, for longer periods of time, to avoid some other flying predator. The predator also adapts to higher altitudes to catch its prey. As this cycle continues for ages, some of the prey species are now drifting in the stratosphere or mesosphere, having evolved protection from the extreme temperature and lack of oxygen. If predator species continued to cause their prey to adapt to greater and greater extremes, they could conceivably evolve to endure the vacuum of space.

 

Once organisms managed to survive within a vacuum, establishing a permanent existence there would be the next step. As time passed, one species would branch into many species to fill many niches, with some venturing back to the surface to carry food and water and oxygen back with it (such as in sacs). Over millions of years, an ecosystem could develop in low orbit.

[Edtharan]

As a hypothetical exercise I find this interesting.

 

Now, instead of developing on a planet, what if the organism developed in space (say like on the dust grains and small asteroids of Saturn's Rings)?

 

Could such a creature exist (maybe just a bacteria like organism - nothing too complex)?

 

It might start by getting it's energy from chemical reactions (breaking down iron/sulphur compounds). Later a form of Photo Synthesis might allow it to get energy from the nearby star.

 

Movement among the dust grains would be a problem, but I think it might be possible with larger organisms or when collisions occur between them. If multicellular organisms develop, you might get something like the bombardier beetles defense as a kind of propulsion system.

 

Thermal regulation would be a big problem. As would radiation.

 

I think it could be possible, but highly unlikely (as compared to the chance of terrestrial abiogenisis - what ever that is).