Origin of Life

[Cypress]

I'm going with #3. If you accept the Big Bang then all of the building blocks were sent out in all directions so there should be nothing unique about life on Earth.

Not a bad point, but the caveat is that only hydrogen and helium condensed from the big bang. Carbon, phosphorus, nitrogen, and associated organic compounds ultimately were manufactured in super novas.

The problem is not with the building blocks of life - organic compounds are ubiquitous in the universe. The challenge is how did these molecules assemble themselves into exceedingly complex, self-replicating cells. Even after 70 years of intensive study, it remains a mystery.

 

[Trumpet]

What came first; the chicken or the egg????????????????????

 

[Trumpet]

4. The origin of life was consistent with chemistry and physics and helped by an outside intelligent agent acting to move it along.

This variant is equally plausible simply because we have not found proof that it cannot have happened, at least as it applies to life on this planet. Now, maybe that doesn't apply to the origin of the first lifeform, but the entire universe is rather a large place so...

So life evolve through hocus pocus.

 

[Cypress]

1. Given the right circumstances it is possible for life to evolve from non life . We are proof of that.
2. Quantum mechanics tells us that (most) anything is possible no matter how small the probability.
3. If you consider time to be infinite then there is an infinite amount of time for the right circumstances to occur for life to evolve from non life again. Conversely it is probable we are not the first form of life to have evolved from non life given that the past is infinite.
4. If you consider the universe to be infinite then there’s an infinite number of possibilities for the right circumstances to have occurred for there to be life elsewhere presently.
That’s my take on it.

A good contribution.

My response is that, as far as we know, space and time are not infinite. We can measure the distance to the cosmic background microwave radiation (CMB), which is presumed to be the limit of the observable universe. According to theoretical physics the CMB represents 400,000 years after the big bang, when photons were able to freely move through the universe.

That places constraints on the size and age of the universe.

13.8 billion years is still a lot if time for biological evolution to occur in the cosmos, if it did.

I keep coming back to the wierd fact that life only evolved once on earth. Every living thing today is a genetic descendent of the first microbes of 3.8 billion years ago. The earth had been around more than 4 billion years, that is almost a third of the age of the universe. If we assume life is so cosmically ubiquitous and resilient, why did life only evolve one time on earth? Why are we not seeing multiple evolutionary events of exotic life forms and life forms of an entirely different genetic heritage?

To me, it either means the evolution of life is an exceedingly rare event; or DNA-based life is the only realistically possible form of life; or maybe ancient Earth did have multiple evolutionary events but we have just not seen the evidence.

 

[NiftyNiblick]

I have always struggled with the concept of backwards infinity.

Forward infinity is easy.
More of the same shit forever.

Backward infinity is hard.
There always has to something that came before that which was before.
There can't ever be a beginning because something had to exist before that.

So for me, it "begins" with sub-atomic particles.
The source of sub-atomic particles is unknowable by a mechanism of human brain capacity.

Once they're there, though, their random confluence in the vacuum of infinite space allows for the existence of everything
that can exist following the physical rules of what sub-atomic particles are capable of becoming.
If space and particles are both infinite, then everything that exists probably exists an infinite number of times.
There are an infinite number of Mother Teresas. There are an infinite number of Banjofucks. And an infinite number of Patriots have won an infinite number of Super Bowls.

Believers of Genesis and Intelligent Design may not agree.
Who, however, can wake up each day on this horrifically imperfect planet and make any credible claim that it's an intelligent design?

 

[ThatOwlWoman]

great points

What is weird to me is that even after 4 billion years, life apparently only evolved once on earth. Every living thing today is a genetic descendent of those first microbes from 3.8 billion years ago.

I just wonder why life did not evolve more than once on earth? If life is so resilient, why didn't different genetic strains of life evolve, or why didn't entirely different life forms evolve here?

Given the set of chemicals life has to work with on this planet, maybe that's the only possibility -- one original life form?

 

[ThatOwlWoman]

I'm going with #3. If you accept the Big Bang then all of the building blocks were sent out in all directions so there should be nothing unique about life on Earth.

Agree. There is likely to be life in other places, maybe with a different chemical base depending on what is available.

We want to believe that we're special, unique. I'm not sure that that's true.

 

[Cypress]

Given the set of chemicals life has to work with on this planet, maybe that's the only possibility -- one original life form?

Good point. It is possible only DNA-based life was possible on earth given the ambient chemical and environmental conditions here.

Another possibility is that there were multiple evolutionary events on the ancient earth, but we do not have the evidence for it.

 

[PostmodernProphet]

Good to see they update the Drake equation. That thing was really nothing more than a wild assed guess

it actually had a singular massive mathematical error.......the real potentials of life supporting planets in any given solar system was either 1 or 0......they then proceeded to multiply the number of planets by the number of suns forgetting the result of multiplying any number times 0........

 

[PostmodernProphet]

1. Given the right circumstances it is possible for life to evolve from non life . We are proof of that.

except the result is not proof of the assumed cause......

 

[ThatOwlWoman]

Good point. It is possible only DNA-based life was possible on earth given the ambient chemical and environmental conditions here.

Another possibility is that there were multiple evolutionary events on the ancient earth, but we do not have the evidence for it.

That's a possibility as well. Maybe at the bottom of ocean trenches, or in the soil underneath Antarctica's ice sheets, we may find something totally new one day.

 

[Dutch Uncle]

Poor Sun. He seems to have a few painful kidney stone passes. I hear the black hole enema is a remedy.

Some think a black hole awaits us all.

 

[Dutch Uncle]

except the result is not proof of the assumed cause......

Correct. Agreed. Exactly like Adam and Eve.

BTW, one of my favorites:

 

[T. A. Gardner]

So life evolve through hocus pocus.

 

[Trumpet]

My point was that it did not originate through hocus pocus, but you're free to believe what you want.

 

[Cypress]

All theoretical, of course, but it's an interesting theory. The timeline seems reasonable.

I like the hypothesis.

Given the vast age of the universe, it certainly makes more sense to think about ancient extinct civilizations, than alien civilizations which just coincidentally and improbably overlap with us in our tiny little time slice of galactic history.

 

[Dutch Uncle]

I like the hypothesis.

Given the vast age of the universe, it certainly makes more sense to think about ancient extinct civilizations, than alien civilizations which just coincidentally and improbably overlap with us in our tiny little time slice of galactic history.

Agreed it's an interesting hypothesis. What doesn't quite make sense to me is why life doesn't beget life just as the human race is beginning to do in our own solar system. It's understandable that civilizations rise and fall, but why would they stop falling unless completely dead?

Even if we nuked our entire planet, some life would continue to persist. In another billion or more years, the planet would be flourishing with life again.

 

[Cypress]

Agreed it's an interesting hypothesis. What doesn't quite make sense to me is why life doesn't beget life just as the human race is beginning to do in our own solar system. It's understandable that civilizations rise and fall, but why would they stop falling unless completely dead?

Even if we nuked our entire planet, some life would continue to persist. In another billion or more years, the planet would be flourishing with life again.

The lesson from Earth at least seems to be that the evolution of intelligent, technologically-capable life is exceedingly rare. Earth itself is almost one quarter the age of the universe, and in all that time only one species evolved capable of technology. And it took 4 billion years just to get there.

If humans (or alien civilizations) self-annihilate or go extinct, the odds of another technologically-capable civilization evolving on the same planet seems slim to none. That does not rule out that non-sentient, lower life would continue to thrive.

That is my read on the hypothesis anyway

 

[T. A. Gardner]

My point was that it did not originate through hocus pocus, but you're free to believe what you want.

Okay, you want to believe that it all happened by random chance on the basis of known chemistry, biology, and physics. I added in the possibility that someone deliberately stirred the witch's caldron to make it happen. It's certainly possible there is other intelligent life in the universe. I'm not counting that out as a possibility, no "hocus pocus" involved.

 

[NiftyNiblick]

I added in the possibility that someone deliberately stirred the witch's caldron to make it happen.

If your theory were true, that somebody did a horribly poor job, especially in consideration of his/her alleged omnipotence and omniscient awareness.

I'd rather take a secular approach than believe in an adversarial and spiteful supreme being, particularly with no real evidence to suggest that the latter exists.

But that's me. Each to his/her own, but don't inject your religious superstitions into the laws of the land.