if you were to seed other parts of the universe for evolving replicators, what would your guiding design ideas be

someone might notice I said for evolving replicators, because the original whatever may not be properly life, the ingredients, and when they land wherever they would likely free run, so all of the possibilities that might evolve could be a computationally large proposition

on perhaps a related subject, of viruses for example, what purpose do they serve, and what energy gradients do they exploit, if any, in organism transformation possibilities

personally I think the ingredients of life here on earth originated elsewhere

>personally I think the ingredients of life here on earth originated elsewhere

that’s a fairly dumb statement really, because it can’t be untrue, given water and so much more originated elsewhere

I mean the early code, simplest encoding if you will, for replication

oh god

SCIENCE said:

oh god

well, you know humans have the capacity to seed life elsewhere in the galaxy now, they have the technology to do it

so, starting there, you know what do you want to do, if took the idea seriously, for and why

transition said:

SCIENCE said:

oh god

well, you know humans have the capacity to seed life elsewhere in the galaxy now, they have the technology to do it

so, starting there, you know what do you want to do, if took the idea seriously, for and why

just a thought exercise, exploring the mind of a hypothetical God if you want, or as metaphor,

Bit of a difficult question, since we don’t know exactly how life began. So what to seed it with I don’t know. Amino acids and stuff seem to be created spontaneously.

But why not just skip that step and go to with seeding it with single cell organisms?

transition said:

if you were to seed other parts of the universe for evolving replicators, what would your guiding design ideas be

someone might notice I said for evolving replicators, because the original whatever may not be properly life, the ingredients, and when they land wherever they would likely free run, so all of the possibilities that might evolve could be a computationally large proposition

on perhaps a related subject, of viruses for example, what purpose do they serve, and what energy gradients do they exploit, if any, in organism transformation possibilities

personally I think the ingredients of life here on earth originated elsewhere

Why would you want to seed life on other planets. It would take billions of years for single celled organisms to evolve further and you would need to be a little over-optimistic to think we would see any outcome. Just leave it to nature.

PermeateFree said:

transition said:

if you were to seed other parts of the universe for evolving replicators, what would your guiding design ideas be

someone might notice I said for evolving replicators, because the original whatever may not be properly life, the ingredients, and when they land wherever they would likely free run, so all of the possibilities that might evolve could be a computationally large proposition

on perhaps a related subject, of viruses for example, what purpose do they serve, and what energy gradients do they exploit, if any, in organism transformation possibilities

personally I think the ingredients of life here on earth originated elsewhere

Why would you want to seed life on other planets. It would take billions of years for single celled organisms to evolve further and you would need to be a little over-optimistic to think we would see any outcome. Just leave it to nature.

In Australia we had the Acclimation Societies where they imported and set free animals and plants and not one did this country any good, in fact they did a tremendous amount of harm. Those that brought them here thought they were improving things for the benefit of all, but they were ignorant of the country and the way it worked, as would be the case interfering in this way with other planets. I would think us going to elsewhere would introduce various microbes, which may or may not survive.

Look to the oceans , the basics of life are there. A bottle of the basic nutrients that provide the conditions and building blocks for simple lifeforms are there.

Given you needs the basics water, nitrates to form proteins and amino chains for plants ,gases and then more advanced life forms from there.

I read an interesting paper a subject about the world’s oceans and seas about 15 years ago now but basically if there was an apocalypse type of event on earth wiping out all life forms on land and in the sea that the ocean has the capacity over time to produce life conditions from the nitrates ->-amino acids/proteins-produce gas exchanges to produce an aquatic environment for simple plant forms and then simple life forms. The stabilising water environment can produce the life forms for seeding rain and essential life supporting gases and food sources for evolving life forms.

monkey skipper said:

Look to the oceans , the basics of life are there. A bottle of the basic nutrients that provide the conditions and building blocks for simple lifeforms are there.

I has all of that just sitting under the frozen surface. Our problem is that we don’t really want to meet new life forms.

Good question.

I suspect it might be much more difficult than might be supposed.

I mean the (observable) universe has billions of billions of planets to play with, but the experimenter would only have one or two.

I think trying out some options in a simulation on Earth would be a good idea.

transition said:

>personally I think the ingredients of life here on earth originated elsewhere

that’s a fairly dumb statement really, because it can’t be untrue, given water and so much more originated elsewhere

I mean the early code, simplest encoding if you will, for replication

Don’t be so hard on transition transition.

Why do you think the ingredients/early code of life originated elsewhere?

It’s not impossible, but I have not seen any evidence to suggest that it is likely.

Bit off topic but I am reminded of “Seed Stock” by Frank Herbert…

 Three years before the era of this story a colony ship of humans arrived at a still unnamed planet and disgorged its cargo and passengers. The planet was harsh and unforgiving; very little of the flora or fauna that the colonists brought with them survived the three years to the time of the story. The only species that seemed to be doing well were the falcons, and they got their food from islands out at sea. Because so many crops failed and animals died, the colonists made their living on a kind of shrimp called trodi that were discovered, first harvested and preserved by a colonial laborer named Kroudar. Kroudar is hideous. He started off ugly, and of all the colonists there the planet has been the harshest to him.

A short man, Kroudar gave the impression of heaviness, but under all his shipcloth motley he was as scrawny as any of the others, all bone and stringy muscle. It was the sickness of this planet, the doctors told him. They called it “body burdens,” a subtle thing of differences in chemistry, gravity, diurnal periods and even the lack of a tidal moon.

Kroudar is one of the only laborers in the whole colony. Everyone else is some sort of scientist. There are class distinctions on the planet, and Kroudar is definitely low-class. He is treated as such at the hands of the colonial masters, even though his efforts have twice saved the them from the slow death of starvation. But Kroudar is also married; to Hanida, a botanist who surprised everyone by choosing Kroudar as a mate. One night Hanida shows Kroudar a project she has been working on. Hanida has spliced together a new strain of maize from the DNA of other maize plants that have managed to survive in the colony’s poor soil. It’s a food source that will likely thrive in this environment. Once Kroudar sees the corn he realizes why Hanida married him; because Hanida has realized that the creatures that are going to survive on this colony are the ones that adapt – the ones that the planet remake into its own. All of the others – most of whom were busy trying hopelessly to duplicate Earth – were doomed. Kroudar, on the other hand, had been busy making himself into a creature of this new planet, just as the falcons already had.

Ian said:

Bit off topic but I am reminded of “Seed Stock” by Frank Herbert…

 Three years before the era of this story a colony ship of humans arrived at a still unnamed planet and disgorged its cargo and passengers. The planet was harsh and unforgiving; very little of the flora or fauna that the colonists brought with them survived the three years to the time of the story. The only species that seemed to be doing well were the falcons, and they got their food from islands out at sea. Because so many crops failed and animals died, the colonists made their living on a kind of shrimp called trodi that were discovered, first harvested and preserved by a colonial laborer named Kroudar. Kroudar is hideous. He started off ugly, and of all the colonists there the planet has been the harshest to him.

A short man, Kroudar gave the impression of heaviness, but under all his shipcloth motley he was as scrawny as any of the others, all bone and stringy muscle. It was the sickness of this planet, the doctors told him. They called it “body burdens,” a subtle thing of differences in chemistry, gravity, diurnal periods and even the lack of a tidal moon.

Kroudar is one of the only laborers in the whole colony. Everyone else is some sort of scientist. There are class distinctions on the planet, and Kroudar is definitely low-class. He is treated as such at the hands of the colonial masters, even though his efforts have twice saved the them from the slow death of starvation. But Kroudar is also married; to Hanida, a botanist who surprised everyone by choosing Kroudar as a mate. One night Hanida shows Kroudar a project she has been working on. Hanida has spliced together a new strain of maize from the DNA of other maize plants that have managed to survive in the colony’s poor soil. It’s a food source that will likely thrive in this environment. Once Kroudar sees the corn he realizes why Hanida married him; because Hanida has realized that the creatures that are going to survive on this colony are the ones that adapt – the ones that the planet remake into its own. All of the others – most of whom were busy trying hopelessly to duplicate Earth – were doomed. Kroudar, on the other hand, had been busy making himself into a creature of this new planet, just as the falcons already had.

Haven’t read that one but it sounds worthy of a perusal.

Could we take existing life from earth, say seeds and everything needed to grow them, water, fertiliser and protective dome and land them on Mars and plant them and see if they grow.

Just a short story.

Interesting ideas though like all of Herbert.

Cymek said:

Could we take existing life from earth, say seeds and everything needed to grow them, water, fertiliser and protective dome and land them on Mars and plant them and see if they grow.

We could but we’d likely fail.

transition said:

if you were to seed other parts of the universe for evolving replicators, what would your guiding design ideas be

someone might notice I said for evolving replicators, because the original whatever may not be properly life, the ingredients, and when they land wherever they would likely free run, so all of the possibilities that might evolve could be a computationally large proposition

on perhaps a related subject, of viruses for example, what purpose do they serve, and what energy gradients do they exploit, if any, in organism transformation possibilities

personally I think the ingredients of life here on earth originated elsewhere

You’re asking really bood questions here.

> if you were to seed other parts of the universe for evolving replicators, what would your guiding design ideas be

My personal preference would be for a range of bacteria, because bacteria are already selected for a wide range of extreme environments. From survival under the surface of rocks, inside solid salt, temperatures up to the boiling point of water (which can be much higher on and under exoplanets) or well below freezing. Oxygen, nitrogen, carbon monoxide or sulphur atmospheres.

But thinking beyond pre-existing life forms …

roughbarked said:

Cymek said:

Could we take existing life from earth, say seeds and everything needed to grow them, water, fertiliser and protective dome and land them on Mars and plant them and see if they grow.

We could but we’d likely fail.

Inside a protective dome, no problem at all. Outside a protective dome, no.

was pondering, if you sketched out an objective for the replicator code, what would it be

I was thinking it need exploit energy gradients, for starters.

transition said:

was pondering, if you sketched out an objective for the replicator code, what would it be

I was thinking it need exploit energy gradients, for starters.

Indeed. Absolutely. It can’t extract energy for replication from constant temperature, or constant chemistry. It must have gradients.

Take a silicon chip for instance, without different doping chemistry you can’t get negative and positive regions so no transistors. A crystal radio relies on the surface chemistry of galena (PbS) crystals. Galena is a semiconductor with a small band gap of about 0.4 eV.

So a big plus for an inorganic replicator would be a sulphide chemistry. A computer program could be etched fairly easily onto the surface of a crystal of sulphide ore. With a place with sulphide chemistry, just add a little heat to get useful metals including copper and silver. That’s much less energy intensive than expecting a computer-style replicator to generate itself using silicon or germanium.

So, let’s get back to carbon based and non-carbon-based lifeforms.

Carbon has huge advantages over all other elements when it comes to building complex molecules at temperatures and pressures that we’re familiar with. And it’s more common than any element in the uinverse other than hydrogen and helium. So the most common minimal chemistry for a replicator is C + H.

Beyond that, it helps replicators if molecules come apart easily, and at normal temperatures and pressures that implies hydrogen bonds. For a hydrogen bond you need an electronegative atom which can be N, O, F, S or Cl. So add that as a third chemical and you’re all set.

Proteins are CHON chemicals, with S thrown into the mix as an unnecessary extra. A carbon-based replicator wouldn’t need proteins, but would need something akin to proteins. One Scifi author suggested liquid crystals as an alternative to DNA, and that is not such a stupid idea. Liquid crystals are also CHON chemicals that interact using hydrogen bonds.

A replicator has to move, and movement requires a liquid to be part of the structure under operating conditions.

Water, you ask. Well, if liquid water is present then we may as well use bacteria as replicators for seeding life. If liquid water is not present, then we have to get creative. A polar liquid is a good start, ruling out simple hydrocarbons. Alcohols can substitute for water in lower or higher temperature environments. Methanol-water mixtures can be stable liquids at temperatures down to 100 ˚C below the freezing point of water.

Carbon disulphide is another polar liquid that can substitute for water. It’s a stable liquid at ambient pressure down to -111˚C.

Low temperature liquids help out if we want to seed life not just on cold planets, but also on cold places with no atmosphere and low gravity.

Then there’s high temperature. Computer silicon chips are stable at temperatures and pressures found on the surface of Venus. But batteries can’t survive there , yet. There’s a research project to develop a battery that can survive under conditions present on the surface of Venus. Water is no good, but there is no end to large organic molecules that remain liquid under those conditions.

A liquid is needed for the replicator to move, and it can’t replicate without movement. Non-polar liquids such as liquid nitrogen, liquid oxygen, paraffins, while useful for robot lubrication, are less useful for carbon-based lifeforms.

High temperatures are also found underground. Molten salt is the easiest replacement for water under high temperature conditions. To take a few at random. Aluminium bromide is liquid between 100˚C and 250˚C. Sodium hydroxide is liquid at temperatures between 325˚C and 1385˚C. Calcium chloride is liquid at temperatures between 775˚C and 1935˚C. Choose a salt that is mineable at the destination.

PS, when seeding life, take a good drill. The centre of Pluto contains very close to the same amount of liquid water as all the oceans on Earth. Which could give it an ecosystem as big as Earth’s.

mollwollfumble said:

transition said:

was pondering, if you sketched out an objective for the replicator code, what would it be

I was thinking it need exploit energy gradients, for starters.

Indeed. Absolutely. It can’t extract energy for replication from constant temperature, or constant chemistry. It must have gradients.

Take a silicon chip for instance, without different doping chemistry you can’t get negative and positive regions so no transistors. A crystal radio relies on the surface chemistry of galena (PbS) crystals. Galena is a semiconductor with a small band gap of about 0.4 eV.

So a big plus for an inorganic replicator would be a sulphide chemistry. A computer program could be etched fairly easily onto the surface of a crystal of sulphide ore. With a place with sulphide chemistry, just add a little heat to get useful metals including copper and silver. That’s much less energy intensive than expecting a computer-style replicator to generate itself using silicon or germanium.

So, let’s get back to carbon based and non-carbon-based lifeforms.

Carbon has huge advantages over all other elements when it comes to building complex molecules at temperatures and pressures that we’re familiar with. And it’s more common than any element in the uinverse other than hydrogen and helium. So the most common minimal chemistry for a replicator is C + H.

Beyond that, it helps replicators if molecules come apart easily, and at normal temperatures and pressures that implies hydrogen bonds. For a hydrogen bond you need an electronegative atom which can be N, O, F, S or Cl. So add that as a third chemical and you’re all set.

Proteins are CHON chemicals, with S thrown into the mix as an unnecessary extra. A carbon-based replicator wouldn’t need proteins, but would need something akin to proteins. One Scifi author suggested liquid crystals as an alternative to DNA, and that is not such a stupid idea. Liquid crystals are also CHON chemicals that interact using hydrogen bonds.

A replicator has to move, and movement requires a liquid to be part of the structure under operating conditions.

Water, you ask. Well, if liquid water is present then we may as well use bacteria as replicators for seeding life. If liquid water is not present, then we have to get creative. A polar liquid is a good start, ruling out simple hydrocarbons. Alcohols can substitute for water in lower or higher temperature environments. Methanol-water mixtures can be stable liquids at temperatures down to 100 ˚C below the freezing point of water.

Carbon disulphide is another polar liquid that can substitute for water. It’s a stable liquid at ambient pressure down to -111˚C.

Low temperature liquids help out if we want to seed life not just on cold planets, but also on cold places with no atmosphere and low gravity.

Then there’s high temperature. Computer silicon chips are stable at temperatures and pressures found on the surface of Venus. But batteries can’t survive there , yet. There’s a research project to develop a battery that can survive under conditions present on the surface of Venus. Water is no good, but there is no end to large organic molecules that remain liquid under those conditions.

A liquid is needed for the replicator to move, and it can’t replicate without movement. Non-polar liquids such as liquid nitrogen, liquid oxygen, paraffins, while useful for robot lubrication, are less useful for carbon-based lifeforms.

High temperatures are also found underground. Molten salt is the easiest replacement for water under high temperature conditions. To take a few at random. Aluminium bromide is liquid between 100˚C and 250˚C. Sodium hydroxide is liquid at temperatures between 325˚C and 1385˚C. Calcium chloride is liquid at temperatures between 775˚C and 1935˚C. Choose a salt that is mineable at the destination.

PS, when seeding life, take a good drill. The centre of Pluto contains very close to the same amount of liquid water as all the oceans on Earth. Which could give it an ecosystem as big as Earth’s.

One further option.

One author has suggested making a replicator out of clay/mica. Clay/mica consists of a sequence of single sheets with electric charges on them. Lining up the charges allows replication given successive cycles of wetting and dehydration. I’m not a particular fan of that but it does point out an alternative to linear replication (DNA and liquid crystals).

The advantage of clay/mica as a replicator is that it eliminates the need for carbon, being made of Mg, Al, Si, O, H.

Some talk of silicon or sulphur as a replacement for carbon. But I have yet to see any evidence that they can be used to build linear macromolecules like carbon. Perhaps in some exotic temperature-pressure domain they can.

The element sequence that is available as raw materials in the universe for building a replicator is quite well known. In sequence it is:
H, O, Si, Na, Al, Ca, K, Fe, Mg, Ti, F, C, P, Mn, S, Sr, Ba, Cl, N.

So nitrogen and carbon (and P and S) are actually a fair way down the list – except in the early universe when heavier elements would have been less abundant. That makes Si-based replicators a worthwhile research topic, but only in areas with low oxygen.

The ratio changes a lot for the surfaces of planets and moons.