Oxford scientists say: Looks like no other intelligent life in whole universe (but keep looking)

[RJM Corbet]

Perhaps because the conditions are now different.

Apart from anything else, the organisms that would be the result of the mutations (and other mechanisms that might be involved) amongst those current-day bacteria and archaea would be entering a world full of existing organisms that are already well adapted to their environments (as opposed to ones that are not so well-adapted).

Eukaryotes: A new timetable of evolution
"Contaminated samples have evidently created some confusion in the timetable of life. On the basis of ultra-clean analyses, an international team, including scientists from the Max Planck Institute for Biogeochemistry, has disproved supposed evidence that eukaryotes originated 2.5 to 2.8 billion years ago. In contrast to prokaryotes such as bacteria, eukaryotes have a nucleus. Some researchers thought they had discovered molecular remnants of living organisms in rock samples up to 2.8 billion years old. However, as the current study shows, these molecular traces were introduced by contamination. The oldest evidence for the existence of eukaryotes is now provided by microfossils that are ca. 1.5 billion years old ..."

The Origin of the Universe, Earth, and Life - Science and Creationism - NCBI Bookshelf.
"The origins of life cannot be dated as precisely, but there is evidence that bacteria-like organisms lived on Earth 3.5 billion years ago, and they may have existed even earlier, when the first solid crust formed, almost 4 billion years ago. These early organisms must have been simpler than the organisms living today ..."

Regardless, prokaryote life continued for around 2 billion years, before the 'quantum jump' to eukaryote? And it only happened that one time?

(References selected at random from Google search so I cannot vouch for them)

 

[RJM Corbet]

I think it's more a case of pessimism at the low criteria held by humans for what qualifies as 'intelligence'.

Post #53

Quoting from Nick Lane (2015):

"Life arose around half a billion years after the Earth’s formation, perhaps 4 billion years ago, but then got stuck at the bacteriological level of complexity for more than 2 billion years, half the age of the planet. Indeed bacteria have remained simple in their morphology (but not their biochemistry) throughout 4 billion years.

In stark contrast, all morphologically complex organisms – all plants, animals, fungi, seaweeds and single-celled ‘protists’ such as amoeba – descend from that single ancestor about 1.5 to 2 billion years ago.

This ancestor was recognisably a ‘modern cell’ with an exquisite internal structure and unprecedented molecular dynamism, all driven by sophisticated nanomachines encoded by thousands of new genes that are largely unknown in bacteria.

There are no surviving evolutionary intermediates, no ‘missing links’ to give any indication of how or why these complex traits arose, just an unexplained void between the morphological simplicity of bacteria and the awesome complexity of everything else. An evolutionary black hole."

(That is on page two, and he goes on explaining the detail for another 300 pages.)

And from the OP article:

We’re all alone: Oxford study says chance of intelligent life elsewhere very low

Paper uses statistics to examine how long it took life to evolve on Earth and how likely each step was; concludes highly unlikely other intelligent civilizations out there

www.timesofisrael.com

“Some transitions seem to have occurred only once in Earth’s history, suggesting a hypothesis reminiscent of Gould’s remark that if the ‘tape of life’ were to be rerun, ‘the chance becomes vanishingly small that anything like human intelligence’ would occur,” the paper says referring to the quote from evolutionary biologist Stephen Jay Gould.

 

[paranoid marvin]

Even if we accept that there is intelligent life here, whether it occurs wherever the conditions are the same as here remains uncertain. 'Undoubtedly' is a statement of faith or of hope.

I think it's more a case of pessimism at the low criteria held by humans for what qualifies as 'intelligence'.

 

[paranoid marvin]

But this is an assumption?

The science is that allowing (obviously) for abiogenesis and the consequent spread of bacterial life, the jump from bacteria to eukaryote by endosymbiosis between bacteria and archaea is hugely unlikely.

It is regarded as an absolutely unique and one-time-only never repeated event upon the planet earth. Bacteria and archaea swarm the earth in billions of trillions -- so why isn't it happening all the time?

Although the abiogenesis of prokaryote bacterial life is possible elsewhere in the universe, the jump to eukaryote> intelligent life is not at all likely?

In the end, if we are going to use terms like infinite and almost infinite -- there are going to be an infinite, or almost infinite, number or worlds that contain an exact, or almost exact replica of me? But is there any justification to assume just because 'me' happened once here -- that I am bound to happen elsewhere too?

It is an assumption, because no other life has yet been found.

But it's almost certain that the universe is vast beyond anything we can imagine. And there is an argument to say that it is still growing. If it isn't infinite, it's as close as you can get. And that assumes there's only one of them.

It's also certain that the universe has been around for a very, very long time. And will continue to be a around for a very, very long time. If it isn't infinite, it's as close as you can get.

In a universe (or universes) that are almost infinitely big, over an almost infinite amount of time, events that are hugely unlikely - even one in a trillion chance - would still be ten-a-penny.

 

[RJM Corbet]

In a universe (or universes) that are almost infinitely big, over an almost infinite amount of time, events that are hugely unlikely - even one in a trillion chance - would still be ten-a-penny.

Yet there are no two snowflakes alike? No two sets of DNA alike? That is what nature shows us ...

 

[Ursa major]

And it only happened that one time?

What we know is that it only happened successfully one time, as far as we can tell...

...where the success is not measured by those organisms coming into existence but by them leaving at least "echoes" of themselves in either the fossil record or in more recent organisms.

If organisms existed, even for long periods of time, but with none of them having left a record of themselves (a record that, importantly, would reveal that their origins were noticeably different from the origin of life of which we know), that doesn't mean that they never existed.

 

[RJM Corbet]

If organisms existed, even for long periods of time, but with none of them having left a record of themselves (a record that, importantly, would reveal that their origins were noticeably different from the origin of life of which we know), that doesn't mean that they never existed.

But there's no reason to assume they did exist either?

 

[paranoid marvin]

Yet there are no two snowflakes alike? No two sets of DNA alike? That is what nature shows us ...

It shows us that it is highly unlikely, but given enough time and enough snowflakes ...

My assertion is mathematics based. Given that something (in this case life) is not impossible, it comes down to frequency. Frequency depends on time frame and volume. The motevplanets there are,the greater the time period given, the more likely something - anything- is likely to reoccur.

And theres nothing to saty that we need the precise circumstances that occurred on Earth for life to occur elsewhere. 4x4=16, but so does 129-113.

 

[RJM Corbet]

My assertion is mathematics based. Given that something (in this case life) is not impossible, it comes down to frequency. Frequency depends on time frame and volume. The motevplanets there are,the greater the time period given, the more likely something - anything- is likely to reoccur.

Perhaps not. A spiral never comes back on itself

Does the mathematical logic lead to the emotional conclusion that there are almost infinite copies of yourself, or close to yourself, out there?

 

[Ursa major]

But there's no reason to assume they did exist either?

1) The absence of proof is no proof of absence.

2) What is wrong with keeping an open mind?

2supplemental) What is the point of having a closed mind?

 

[RJM Corbet]

1) The absence of proof is no proof of absence.

2) What is wrong with keeping an open mind?

2supplemental) What is the point of having a closed mind?

Would you apply the same reasoning to the existence of werewolves?

 

[BAYLOR]

Heyt RJM , how are you , haven't seen you here in

Perhaps not. A spiral never comes back on itself

Does the mathematical logic lead to the emotional conclusion that there are almost infinite copies of yourself, or close to yourself, out there?

And if someday, we build ships that can go. between stars at less then the speed of light, given the time it takes to travel, we may arrive at given star which may have given rise t to intelligent species but we may are after they've come and gone .

If we could only go faster then light.

 

[Ursa major]

Would you apply the same reasoning to the existence of werewolves?

I'm someone who doesn't go into believing things, i.e. accepting** something as true (or false, for that matter) without sufficient evidence for it being so. If I don't know, one way or the other, I keep an open mind.

Werewolves, as usually depicted, couldn't exist in the real world: almost instantaneous (and reversible) metamorphoses are simply impossible, as are the similarly reversible changes in mass involved. (Even on the level of the small details, it's nonsense: even if the hair/fur could grow that quickly, where does it all go when the werewolf returns to its human form?)


** - I do, of course, resort to the balance of probability when I need to make a decision on something and have no means of determining the truth of the matter in the short time available. The matter we're discussing is not something to which that need applies.

 

[RJM Corbet]

Heyt RJM , how are you , haven't seen you here in


And if someday, we build ships that can go. between stars at less then the speed of light, given the time it takes to travel, we may arrive at given star which may have given rise t to intelligent species but we may are after they've come and gone .

If we could only go faster then light.

Thanks @BAYLOR
Am enjoying reconnecting

Yes. So the reasoning is whether intelligent life (probably) exists in the observable universe? Because anything could exist in an infinite universe -- flying teapots and upside down trees?

I'm someone who doesn't go into believing things, i.e. accepting** something as true (or false, for that matter) without sufficient evidence for it being so. If I don't know, one way or the other, I keep an open mind.

Werewolves, as usually depicted, couldn't exist in the real world: almost instantaneous (and reversible) metamorphoses are simply impossible, as are the similarly reversible changes in mass involved. (Even on the level of the small details, it's nonsense: even if the hair/fur could grow that quickly, where does it all go when the werewolf returns to its human form?)


** - I do, of course, resort to the balance of probability when I need to make a decision on something and have no means of determining the truth of the matter in the short time available. The matter we're discussing is not something to which that need applies.

Obviously there can be no prediction of chance from a singular occurrence. But conversely the fact a thing happened once does not make it any more likely to happen again?

 

[BAYLOR]

Yes. So the reasoning is whether intelligent life (probably) exists in the observable universe? Because anything could exist in an infinite universe -- flying teapots and upside down trees?

Obviously there can be no prediction of chance from a singular occurrence. But conversely the fact a thing happened once does not make it any more likely to happen again?

Glad you're back.


If we exist then , it's not inconceivable that other intelligent life forms exist in the universe.

 

[RJM Corbet]

Glad you're back.


If we exist then , it's not inconceivable that other intelligent life forms exist in the universe.

But not definite, or even probable within the observable universe limited by the speed of light from Earth?

To repeat (concerning the OP)
Quoting from Nick Lane
The Vital Question
(2015)

"Life arose around half a billion years after the Earth’s formation, perhaps 4 billion years ago, but then got stuck at the bacteriological level of complexity for more than 2 billion years, half the age of the planet. Indeed bacteria have remained simple in their morphology (but not their biochemistry) throughout 4 billion years.

In stark contrast, all morphologically complex organisms – all plants, animals, fungi, seaweeds and single-celled ‘protists’ such as amoeba – descend from that single ancestor about 1.5 to 2 billion years ago.

This ancestor was recognisably a ‘modern cell’ with an exquisite internal structure and unprecedented molecular dynamism, all driven by sophisticated nanomachines encoded by thousands of new genes that are largely unknown in bacteria.

There are no surviving evolutionary intermediates, no ‘missing links’ to give any indication of how or why these complex traits arose, just an unexplained void between the morphological simplicity of bacteria and the awesome complexity of everything else. An evolutionary black hole."

 

[Ursa major]

Obviously there can be no prediction of chance from a singular occurrence. But conversely the fact a thing happened once does not make it any more likely to happen again?

And...?

If one does not know something and not knowing it makes no practical difference, why the insistence that one has to come down on one side or the other? It's irrational.

 

[RJM Corbet]

And...?

If one does not know something and not knowing it makes no practical difference, why the insistence that one has to come down on one side or the other? It's irrational.

It comes back to the OP?

We’re all alone: Oxford study says chance of intelligent life elsewhere very low

Paper uses statistics to examine how long it took life to evolve on Earth and how likely each step was; concludes highly unlikely other intelligent civilizations out there

www.timesofisrael.com

 

[Ursa major]

You mean the "the chance of intelligent life elsewhere is low"...?

"Chance" indicates a lack of definitive evidence/knowledge and "Low" is not "Zero".

 

[RJM Corbet]

You mean the "the chance of intelligent life elsewhere is low"...?

In the observable universe vanishingly so, in the estimation of experts...

Chance" indicates a lack of definitive evidence/knowledge and "Low" is not "Zero".

Ok