If humanity became extinct at some point in the future

[Country Boy]

 

Time's a bugger, don't you think? An enigma pretending to be a puzzle; time is wobbly with a dash of wibble, so please stop asking or you'll wibble your wobble...

 

So "timey-wimey" stuff?

[Itoero]

The question depends on why all life has died.

An asteroid.

[dimreepr]

An asteroid.

 

Given the earths history, that would need to be a bloody big asteroid to destroy all life, however if it doesn't strip the earth of it's atmosphere and oceans, I see no reason why life couldn't start again.

Edited May 3, 2017 by dimreepr

[Bender]

If all life dies, do you think abiogenesis can happen again?

With a sample size of one, we don't have much to go on. Given the fact that abiogenesis seems to have happened only a couple of hundred million years after the first oceans on Earth, I'd put my money on it happening again given similar circumstances.

[Strange]

Remember, though, that there was no oxygen in the atmosphere the.

[Itoero]

Remember, though, that there was no oxygen in the atmosphere the.

Did life create oxygen?

[Thorham]

If humanity became extinct at some point in the future, how long will it take for all of our science (all of our physics and chemistry and biology) to be rediscovered again by a different species?

 

It may not have to be rediscovered.

 

1. Humans evolve into another species with equal or greater intellect.

2. Humans replace their bodies with machines.

3. Humans bioengineer themselves into a new species.

 

In all these cases our knowledge won't be lost.

 

Edited May 4, 2017 by Thorham

[Bender]

Remember, though, that there was no oxygen in the atmosphere the.

If no life is left to maintain the oxygen level, it will be gone pretty quickly. Oxygen has a tendency of reacting with nearly everything that isn't already oxidised.

 

I have no idea how long it will take, but even if it takes millions of years, that has little to no impact on the entire duration.

 

Except if the probability of abiogenesis increases dramatically under an oxygen atmosphere and it would happen even before the oxygen was gone. Depending on how life on earth was removed, there could be a lot of other chemicals left to accelerate the process.

Edited May 5, 2017 by Bender

[zapatos]

Given the earths history, that would need to be a bloody big asteroid to destroy all life, however if it doesn't strip the earth of it's atmosphere and oceans, I see no reason why life couldn't start again.

I have my doubts. Given that we've only observed the results of life originating once on this planet in billions of years, I suspect we either currently have the wrong environment for it, or it is simply extremely rare.

[dimreepr]

I have my doubts. Given that we've only observed the results of life originating once on this planet in billions of years,

 

According to this Wiki timescale, life didn't take very long (certainly not billions of years) to start after water appeared.

 

I suspect we either currently have the wrong environment for it, or it is simply extremely rare.

 

 

This looks like a non sequitur, given the above.

[zapatos]

This looks like a non sequitur, given the above.

So are you saying that our environment is similar to what it was billions of years ago, or are you saying that one occurrence of life forming in four billion years is not all that rare?

[Prometheus]

I have my doubts. Given that we've only observed the results of life originating once on this planet in billions of years, I suspect we either currently have the wrong environment for it, or it is simply extremely rare.

 

The condition that prevents new life from emerging could be extant life.

[zapatos]

The condition that prevents new life from emerging could be extant life.

Or not...

[dimreepr]

So are you saying that our environment is similar to what it was billions of years ago, or are you saying that one occurrence of life forming in four billion years is not all that rare?

 

We have no idea if only one form of life occurred 4 billion years ago, perhaps it happened multiple times in that era and only one survived or perhaps DNA is the only way life can establish.

Edited May 5, 2017 by dimreepr

[zapatos]

We have no idea if only one form of life occurred 4 billion years ago, perhaps it happened multiple times in that era and only one survived or perhaps DNA is the only way life can establish.

You called my suggestion that we might currently have the wrong environment for life to form, or that the formation of life is a rare happening, a non-sequitur.

 

As the basis of your conclusion you used a reference showing that life on earth began one time, over four billion years ago, 124 million years after water showed up.

 

I'm trying to figure out why you think that a single known occurrence of life forming on earth four billion years ago, means that my suggestion that either the environment we have now is wrong for life, or that the formation of life at all is a rare thing, is illogical.

 

And you now seem to be buttressing your assertion that my argument is illogical by making speculations for which there is no evidence.

 

What part of my argument is illogical and why?

 

Seems to me that calling my statement illogical was a bit unfair.

[dimreepr]

You called my suggestion that we might currently have the wrong environment for life to form, or that the formation of life is a rare happening, a non-sequitur.

 

As the basis of your conclusion you used a reference showing that life on earth began one time, over four billion years ago, 124 million years after water showed up.

 

I'm trying to figure out why you think that a single known occurrence of life forming on earth four billion years ago, means that my suggestion that either the environment we have now is wrong for life, or that the formation of life at all is a rare thing, is illogical.

 

And you now seem to be buttressing your assertion that my argument is illogical by making speculations for which there is no evidence.

 

What part of my argument is illogical and why?

 

Seems to me that calling my statement illogical was a bit unfair.

 

I said it looks like a non sequitur (I meant no disrespect), since the timescale is very small (in cosmological terms) and our current environment has produced synthetic life.

 

http://www.bbc.co.uk/news/10132762

 

https://en.wikipedia.org/wiki/Artificial_life

 

https://en.wikipedia.org/wiki/Artificial_chemistry

[zapatos]

I said it looks like a non sequitur (I meant no disrespect), since the timescale is very small (in cosmological terms) and our current environment has produced synthetic life.

The timescale for Earth and sun is only eight billion years, and we have already passed the half-way point. We are 13 billion years into the life of the universe. And yet we have evidence of life occurring only once during the first half of the life of the earth, and no indication life exists anywhere else in the universe.

 

None of this indicates new life forms won't bloom on Earth during the next four billion years if all current life on Earth is wiped out, but I think it is reasonable to suggest that the formation of life here might be rare.

 

I also fail to see how the existence of synthetic life in our current environment, requiring both man and other pre-existing forms of life to create, is any indication that life can begin again if all existing life leaves the planet.

[dimreepr]

None of this indicates new life forms won't bloom on Earth during the next four billion years if all current life on Earth is wiped out, but I think it is reasonable to suggest that the formation of life here might be rare.

 

 

Maybe, but there's nothing to suggest it can't or that life is rare.

[zapatos]

Maybe, but there's nothing to suggest it can't...

Good thing I never argued otherwise then...

 

...or that life is rare.

We are talking about the formation of new life if existing life is wiped out from this planet.

And yes, there is something to suggest that the formation of new life on this planet is rare. Of all the forms of life we have examined that exist on this planet, all have a common ancestor.

[dimreepr]

All the evidence we have, is that life formed shortly after 'liquid' water was present on earth.

Edited May 5, 2017 by dimreepr

[zapatos]

That's my point. In the ensuing four billion years we've never seen it happen again.

 

Your refusal to acknowledge that a single known event in four billion years constitutes a rare occurrence seem disingenuous.

[StringJunky]

Your refusal to acknowledge that a single known event in four billion years constitutes a rare occurrence seem disingenuous.

Perhaps all ecological niches are filled that disallow the formation of new life forms.

 

That's my point. In the ensuing four billion years we've never seen it happen again.

 

There could have been multiple, concurrent variants in the initial period, but only one dominated and has lasted the full distance, hence, the single common ancestry.

[zapatos]

Perhaps all ecological niches are filled that disallow the formation of new life forms.

 

There could have been multiple, concurrent variants in the initial period, but only one dominated and has lasted the full distance, hence, the single common ancestry.

Perhaps we are the only life that ever did or ever will form in the universe.

 

There could have been a recycling universe and after billions of iterations we are still the only place life has ever started.

 

Speculations are great fun, but when we look at actual data points, we still have evidence for only one start of life. Given the data thus far it is not unreasonable to suggest that abiogenesis may be a rare event.

[Bender]

Speculations are great fun, but when we look at actual data points, we still have evidence for only one start of life. Given the data thus far it is not unreasonable to suggest that abiogenesis may be a rare event.

We know it happened quickly after the circumstances where suitable.

 

We also know that if different life forms have to compete for resources, only the "fittest" survive. It would be pretty hard for any new candidates to compete with all the life forms that have adapted to all possible environments. In other words: the circumstances are not suitable to give abiogenesis a fair chance, so conclusions about its rareness cannot be drawn.

Edited May 6, 2017 by Bender

[Prometheus]

Perhaps we are the only life that ever did or ever will form in the universe.

 

Or not.

 

 

Found this interview with an evolutionary biochemist quite interesting.

 

There are two big differences today which mean that life is almost certainly not continuing to arise even in these favourable settings. One is the chemistry of the oceans. Four billion years ago, there was no oxygen and much higher CO2 levels which together are much more conducive to life and then secondly, today's vent systems are already packed with living cells which are far more effective at converting raw materials such as hydrogen and CO2 into biomass than any primitive prebiotic system could be. So, however likely life might have been at the beginning, it's extremely unlikely that life could originate again on Earth today.