Making a World

I'd like to take some time and some space for us to envision a world in a faraway star system, perhaps beyond our Milky Way Galaxy.

Let's make this planet be within the habital regions of whatever star it orbits. Since we want life to evolve on this planet, we have to make it a less massive star, one with a life-span of at least 6 billion years. If we put our planet around a blue or white super-giant star, the star will burn for only a few tens of millions of years or less before going nova, so life won't have a chance at evolving anything past molecular stages.

I do want to make this a hotter star though - one with a little more radiation coming off of it. It's probably a bit whiter than our star appears to be from Earth.

Let's also say this planet forms at a distance a little bit further away from that sun than our Earth is from our sun. Essentially, since the star's warmer, the planet will be warmer, but since it's a little bit further away, it'll be cooler. Essentially we should end up with a planet of similar temperatures that one would have that travelled 1/3 of the way to Venus.

How large will this planet be? Well, I'd like to say it'd be small - that as our own system demonstrates, gases close to a star are quickly sucked up by that star, and gases further away form gas giants, not having had time to be incorporated into the sun.

However, we have found systems where huge gas giants orbit their respective suns at distances like that of Mercury - though most do tend to be away from their parent star at a distance like Pluto or further (though it should be noted that these are super-giants we have discovered, some more than ten times the mass of Jupiter, and so have been detectable through measuring stellar "wobbles" - other, very different, solar systems may yet exist).

So let's increase the amount of dust that collected to form this planet we'll name Prometheus. Prometheus has a gravitational force of 1.5Gs, and a diameter about a quarter greater than the earth.

Prometheus is also made from a lot of heavy elements, much like Earth. We have Carbon, Iron, some gold and other things. However, unlike the Earth, Prometheus will not have a moon. In fact, unlike the earth, almost all of the metals are buried inside the planet - since whilst the planet was molten, density differences made all the elements form into their own sections around the core. At the same time this means that whilst Gold will be far down into the planet, it is concentrated at that depth. We could call it "the gold sphere". Carbon, thankfully, is a light element, and so will rise to the top. This is why Earth's crust is predominantly carbon. Why do we have so many precious elements? Well, early in earth's history - a planetoid roughly the size of Mars crashed into the Earth, sending elements from within the core, out to a rapidly cooling surface - and so a lot of the heavy metals were brought to outside the surface, though still the majority remain in their sections beneath the earth (Iron's at the center being one of the most dense, and also most abundant, elements in the earth).

On the surface we have hydrogen, helium, some amonia, and other trace gases. Oxygen doesn't exist - or where it does exist it is quickly and voraciously consumed by hydrogen, and intense heat during the earth's cooling has forced it to combine with a lot of carbon. Still, we end up with a lot of water, if oxygen is present, and carbon dioxide - but almost no pure oxygen. It's all locked up. On earth, our gravity allowed hydrogen and helium to drift away - being too light a substance to remain locked in by gravity. On Prometheus, however, perhaps hydrogen and helium still exist.

So, now, on this world - life has a chance to evolve.

At first all the elements are here for the creation of carbon based life. As shown by expirments, utilizing electric arcs and pulses to simulate lightning or long-duration UV exposure, amino acids and even simple proteins quickly come into existance. The atmosphere of Saturn's moon, Titan, is proof that when these basic elements exist, and energy is introduced, the buildingblocks of life are quickly constructed.

We know that, eventually, a protein, or acid, or some kind of complex combination of random factors will cause a molecule like, though maybe not exactly like, DNA to form. In fact, multiple kinds of molecules like DNA could form. Quickly they'll begin to consume the organic soup of chemicals that is still being created in the skies above. They're not expelling any waste - using only the natural resources around them to make either copies of themselves, or perhaps just longer and longer versions of themselves - like a self-combining polymer that just stretches on like an endless strain of DNA.

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Well, here's some groundwork. I have 150 characters left (exactly 150 at the "0"), and so I'll either continue on later, or let you, the reader, add on to this exciting topic.

-Thank you.

So here we have the planet Prometheus - just starting to blossom with life forms.

In order to diverge from earth-like systems, I'm going to go with the "living polymer" life-form.

As a quick recap, this is a molecule, like DNA, that - instead of making seperate copies of itself, creates copies or extensions of its own molecular chemistry by adding new pieces to itself continuously. Think of it as a piece of plastic (a carbon polymer) that, instead of needing us to connect new pieces of carbon into the polymer molecule, would be created by life forms, but perhaps as a different kind of molecule. Essentially, it's a living plastic.

Now, I discussed some of this with my sister, who is a medical student at Queen's University in Kingston, and she asked me some questions on how such a life-form would survive.

One question was UV light. This living polymer, when it comes into contact with large amounts of UV light (such as at the surface of this organic pond where our life-forms are arising) will be killed - the bonds connecting the polymer together become energized enough that the bonds between the atoms fall apart (the molecule literally shakes itself to pieces). I'm thinking that's a GOOD thing though. As the life-form is drawn up to the surface, it would reproduce (grow bigger pieces of itself). Close/at the surface it would be broken apart. Either it's broken apart into the original pieces again (which could just be used by still-living pieces to reconstitute or grow some more), or it would break apart only pieces of the molecule, thus making a molecule that has, forcefully, been reproduced.

The pieces of the molecule on the surface of this pond would then, along with the water around them, vent the excess heat, and would drop to the bottom of the pond again - allowing the cycle to begin again.

Congradulations, we have made life.

And it's not entirely like our own either. This seems to be a sort of "Necro-Synthesis", which is very similar to photosynthesis.

PROBLEM: Is this life?

It's not reproducing under its own power. It's requiring an EXTERNAL source to reproduce.

However, Viruses are the same, are they not? Without a host cell to infect, a virus does NOT act "alive". Once it encounters a cell, then it uses the cell's power to reproduce. A virus does NOT reproduce under its own power either. Do you consider a virus alive? Some people say no... and I believe our life form right now also falls under this grey zone between "life" and "replicating molecule".

Where does life go from here?

Well, for one, we did mention that other kinds of life could arise around the same time. Perhaps one form of life would even be spawned, once again totally by accident, from this living polymer. Let's say this did happen. This life form could be something very similar to the original - grow and shed, grow and shed. However, perhaps it would use proteins that it creates itself to break down its originator. It would be another living polymer that would feed off of the original.

However, this polymer uses a more complex protein. Also, if this protein can't make food out of the original organic soup (which is slowly disappearing), then it's dependant on the original, and will obey the limitations of an eco-system. Whenever this polymer eats too much of the other, it dies off, allowing the original to grow back again, until the cycle renews itself.

Now that there is COMPETITION though, we drive forward our evolution of life on this planet! Competition encourages diversification. Small changes in each of these polymers that didn't do anything good for the original before (or, indeed, could have harmed it), now become useful traits in light of this competition. Evolution can now go into full swing.

By the time we get to this point, 4 or even 5 billion years of the life of this planet may soon be over. There's not that much life left in the star, but it still should shine about just as bright for another 1 or 2 billion years - a long time considering that life on earth went from life-forms like algae to you and me in less than half a billion years.

However, life on Prometheus now has a set pattern. It's complacent in the way it does things, and it does things well. Any shockingly new life forms that arise may well be squeezed out by this, far more evolved, form of competition. The cycle - a very true form of life and death, as well as a small predator-prey relationship.

The next step for the original polymer may be to evolve the production (assembly, like how it assembles itself) of proteins that can form the organic molecules that the polymer uses to grow out of things like water, earth, and sun. Essentially, it'd be something like photo-synthesis, but unlike DNA this Living Polymer (we'll call it LP) does not reproduce of its own accord.

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Okay, so I now have only 94 more characters left at this point. I'm going to waste it here again and people do contribute.

Once again, a recap, we have a planet, and we have life in the form of LP (Living Polymer). There are 2 main kinds of LP - one which uses the broken down pieces of itself or the other kind of LP to grow, and the other which feeds directly off the first. We'll say the first is most like a polymer, and so it's the PLP, and the other is most like a living creature, so we'll call it LLP.

Now, as the organic soup that these life-forms came from begins to eat itself up, food will become scarce for PLP and LLP. It would only be surviving off of its own dead pieces. LLP is then also unable to easily survive, since its food source would be dwindling - it would have to evolve a maximum limit to its growth, with extra pieces that grow on it falling off (we have something like cell-division, though very different). Harsh circumstances are part of competition, and so new evolutionary traits grow into ascendance. Eventually, using proteins something like what it uses to break down the PLP, the LLP will find a way to break down the carbon in the rocks or from the carbon dioxide in the air, and combine them into the pieces it needs to grow using sunlight. LLP develops photo-synthesis.

Other pieces of LLP, however, don't acquire this trait, instead they get tougher and develop a taste for LLP. We have an animal-plant relationship now.

PLP, meanwhile, grows where it can, but will eventually die out - becoming consumed by the two strains of LLP. We have our first extinction.

So let's rename things. PLP can now refer to the polymer that is most like a Plant, and ALP can refer to the polymer most like an animal. Both PLP and ALP also form into things like cells. They're not cells like we would know them - though. These are much smaller cells, just collections of the DNA-like Living Polymer. There's no internal processes as we would know them, except for maybe a few proteins or smaller living polymers existing with the LLP that limit its growth.

At this point, now that competition still exists, and we have plants and animals, we'll enter the "Promethian Explosion" much like the Cambrien Explosion that occured on earth, when all sorts of creatures came into existance.

ALPs and PLPs will develop different kinds of polymers working together, a sort of "outside" and "inside" cell structure. For the PLPs this would probably be Protective Cells and Growth Cells. Protective Cells wouldn't grow as fast, but would grow around the Growth Cells, like skin, protecting the polymer from UV radiation (which has been dwindling every since photosynthesis began to create the oxygen atmosphere of the planet). Growth cells would just reproduce like the originals, but would also form into clusters that might break off of the original PLP and form a new plant. In a sense, this is the first seed.

ALPs, meanwhile, would develop many more complex cells. Some cells would be protective, as before, but since they can't depend on the sun like the PLPs, they need ways of openning up to ingest their material. Transitive Cells arise - cells that break down PLPs in front of them, but down ingest all the material - giving most of it into the Growth Cells within it. Some kind of Movement cells would be needed - perhaps something like a catepillar - a cell that could stretch and shrink according to chemical signals recieved from Chem-Cells, a cell that would produce certain chemicals, recieving information from chemical signals from the Protective Cells about their surroundings.

Our first plants thrive under the new conditions, and may even start to leave the ocean. They wouldn't have leaves, like we'd imagine. Instead, they'd be mats of life - a sort of living rubber. Bulbous forms of PLPs could appear, holding acids or toxins within them to kill ALPs that venture too near, or which start taking bites out of them.

ALPs would continue to produce many more extremely complex creatures. Some may be able to use the expanding-contracting Movement Cells as a sort of Muscle Cell to move pieces of themselves inside themselves elsewhere. Some ALPs may become Fungus, forgoing the Movement Cells and relying on Transitive Cells - the Growth Cells becoming Spores.

Other ALPs may become things like Amebas, consuming perhaps even other ALPs around them for the basic constituent parts of themselves.

I have 650 characters left, but have to leave early. I hope to be back later to continue the evolution of life on Prometheus. Perhaps someone else will start adding in some of the odd creatures we might find?

Later.