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

[RJM Corbet]

I don't understand the question.

Would you care to link the research papers you're referring to? Or are you just going by opinions in newspaper articles?

 

[Swank]

Would you care to link the research papers you're referring to? Or are you just going by opinions in newspaper articles?

I'm not "going by" any opinions. I haven't taken a position, other than pointing out that if a scientist who studied something calls it "probable", that scientist has a more informed opinion than someone who has not studied the topic in any depth.

Informed skepticism comes from the same place as informed opinion.

 

[Swank]

One thing that I think gets ignored is that adaptation is a response to some sort of upheaval. Long periods without major evolutionary change might be long periods of environmental stability - which shouldn't count against the likelihood of intelligence emerging any more than a rain delay means that noone is scoring a home run in baseball.

Why have turtles changed so little? Because it is a boringly stable strategy, not because there was a lack of time or opportunity.

 

[Vertigo]

Yes, it's not a concrete piece of research. It's a thought piece where they sketch out a response to what I believe is another thought piece that expanded on the "hard step model". Which is a highly simplified model of evolutionary processes and history. (I had a look a few papers suggested!)

All I take from the Penn state people is that they are saying, evolution 'hard steps' may not really be hard steps. Just when the conditions are right life 'finds a way' quite quickly and things like eukaryotes will appear, or complex multicellular life, photosynthesis, abiogenesis etc.

But then, taking into account all the various elements that life hard steps would need to be present - say astronomical and geological considerations, or previous developments having run long enough to change geochemical conditions (say built up an oxygen atmosphere) may very well return the probability of each hard step as a whole to be unlikely and take much longer.

They post no hard evidence, in fact they end with saying the following three basic lines of attack:

Earth and life scientists could work together to determine when Earth’s surface environment first became supportive of each proposed hard step

Evolutionary biologists and palaeontologists could better constrain how many times each hard-step candidate occurred.

Lastly, astronomers could use data from planets beyond the solar system to figure out how common life-hosting planets are, and how often these planets have hard-step candidates, such as oxygen-producing photosynthesis and intelligent life.

Needless to say, the last point all I can say, is

duh, yeah. That'd be handy data to have

Yes, that's a more articulate expression of my own take away from this!

 

[Brian G Turner]

I'm afraid I still don't buy it. It all seems more like speculation than a concrete piece of research.

Agreed, but in the absence of evidence speculation helps. After all, the hard steps model is also speculation.

I really don't think humanity changed the ecological or chemical conditions significantly until the last 10k years and probably only really in the last 4-5k years.

My original reading was that they were talking about the emergence of new lines from endosymbiotic events?

One thing that I think gets ignored is that adaptation is a response to some sort of upheaval. Long periods without major evolutionary change might be long periods of environmental stability

Quite true.

Perhaps the bigger problem with the whole discussion is the focus on intelligence - as if measuring life according to a human-centric view. I wonder if the discussion would be different if it focused more on complexity? Am simply thinking aloud.

 

[Vertigo]

Agreed, but in the absence of evidence speculation helps. After all, the hard steps model is also speculation.


My original reading was that they were talking about the emergence of new lines from endosymbiotic events?


Quite true.

Perhaps the bigger problem with the whole discussion is the focus on intelligence - as if measuring life according to a human-centric view. I wonder if the discussion would be different if it focused more on complexity? Am simply thinking aloud.

I tend to agree; I still think complexity was likely the hardest step. But as you say it's only speculation.

I agree the hard steps model is also only speculation, though the apparent low frequency still makes it feel more likely to me. Really, in the absence of a time machine or more examples, which both seem pretty remote at the moment, all of this will only ever be speculation.

 

[Venusian Broon]

I tend to agree; I still think complexity was likely the hardest step. But as you say it's only speculation.

What do you mean by complexity? It seems that if you have cells with a heredity mechanism like DNA, evolution will give rise to complexity of some form inevitably, IMO. Multicellular life is thought to have arisen independently at least 25 times from what we know. (But that might not be what you meant!)

 

[Vertigo]

What do you mean by complexity? It seems that if you have cells with a heredity mechanism like DNA, evolution will give rise to complexity of some form inevitably, IMO. Multicellular life is thought to have arisen independently at least 25 times from what we know. (But that might not be what you meant!)

I was thinking of the evolution of eukaryotes and on up from simple microbes. But mainly the eukaryotes.

 

[Swank]

Perhaps the bigger problem with the whole discussion is the focus on intelligence - as if measuring life according to a human-centric view. I wonder if the discussion would be different if it focused more on complexity? Am simply thinking aloud.

I don't think there has been a lack of complex life on earth since well before the dinosaur. What people seem to get worked up about here and everywhere else in the universe is that animals like us - that write, make complex tools and broadcast I Love Lucy - aren't common. And that seems to be the thing this study is trying to address - that the timescale is perfectly valid to get one "intelligent" genus in a billion years, given that it is just a single solution to the adaptation problem.

And all the handwringing comes because we haven't found fossils of anything we think is sufficiently intelligent (even though there is no reason to think we would ever find fossils to all life), and that we haven't seen evidence of intelligence elsewhere, despite the fact that we expect to find it within a 100 year window AND normal radio broadcasts aren't necessarily powerful enough to detect. All of which is short sighted, impatient and perhaps juvenile. Like a child having a fit about a lost toy after 30 seconds of searching.

I think we are really deluding ourselves when we get frustrated by our seeming solitude. The universe isn't working well with the human timescale and we just aren't adapting.

 

[RJM Corbet]

Agreed, but in the absence of evidence speculation helps. After all, the hard steps model is also speculation.


My original reading was that they were talking about the emergence of new lines from endosymbiotic events?


Quite true.

Perhaps the bigger problem with the whole discussion is the focus on intelligence - as if measuring life according to a human-centric view. I wonder if the discussion would be different if it focused more on complexity? Am simply thinking aloud.

But in the the midst of speculation and absence of concrete evidence for multiple pathways, the evidence stands for a singlular LECA? Last Eukaryote Common Ancestor?

 

[Cthulhu.Science]

But in the the midst of speculation and absence of concrete evidence for multiple pathways, the evidence stands for a singlular LECA? Last Eukaryote Common Ancestor?

Yes, she called herself Eunice.

 

[RJM Corbet]

But the issue is that the single origin is encoded in the eukaryote cell. The evidence is there. And so if other pathways petered out, the fact remains that only one pathway succeeded in two billion years, although there has been lots of time since then for new pathways?

Unlike the evidence for singular origin, there's no evidence for these alternate pathways -- just speculation about specific conditions, and so on?

 

[Karapace]

But the issue is that the single origin is encoded in the eukaryote cell. The evidence is there. And so if other pathways petered out, the fact remains that only one pathway succeeded in two billion years, although there has been lots of time since then for new pathways?

Unlike the evidence for singular origin, there's no evidence for these alternate pathways -- just speculation about specific conditions, and so on?

A few things spring to mind.
1. the conditions on earth are particularly well suited to eukaryotic life and all other types were out competed very quickly
2. confirmation bias. We only find what we are looking for.
3. the high unlikelyhood of finding any fossil evidence for different types of early life.
4. early Archaic life killed off the rest (Great Oxidation Event - Wikipedia) edited: as I realised that Eukaryotes were not the earliest forms of life
Third edit (having just read up on it all, boy is it complex and full of speculation) there is the 5. possibility that there was no absolute universal ancestor but life arose out convergent evolution of several potential lines following a similar pathway

 

[Vertigo]

...and all other types were out competed very quickly

I'm not sure I'd describe bacteria as having been out competed!

having just read up on it all, boy is it complex and full of speculation

But you're absolutely right and therein lies the ultimate problem. All these other things are possible but really it seems unlikely we'll ever know definitively!

 

[BAYLOR]

A few things spring to mind.
1. the conditions on earth are particularly well suited to eukaryotic life and all other types were out competed very quickly
2. confirmation bias. We only find what we are looking for.
3. the high unlikelyhood of finding any fossil evidence for different types of early life.
4. early Archaic life killed off the rest (Great Oxidation Event - Wikipedia) edited: as I realised that Eukaryotes were not the earliest forms of life
Third edit (having just read up on it all, boy is it complex and full of speculation) there is the 5. possibility that there was no absolute universal ancestor but life arose out convergent evolution of several potential lines following a similar pathway

I'm not sure I'd describe bacteria as having been out competed!


But you're absolutely right and therein lies the ultimate problem. All these other things are possible but really it seems unlikely we'll ever know definitively!

Burgess Shales Weird wonders in Smithsonian Magazine. Interesting stuff there.

 

[Brian G Turner]

But in the the midst of speculation and absence of concrete evidence for multiple pathways, the evidence stands for a singlular LECA? Last Eukaryote Common Ancestor?

I suspect there's a misunderstanding about this in general, and that we're more likely looking at a wider population event rather than an individual event. In other words, that multiple instances could have happened at the same time, and that all later populations of eukaryotes evolved from these.

Additionally, when primary endosymbiosis happens, the newly formed organ loses it's own genetic diversity over time. So I would have thought it's actually impossible to define it as a single event involving one individual, as opposed to a population change.

Otherwise IMO looking for a single individual LECU or LUCA or similar is like assuming that once there were no humans and there was suddenly one, from which all humans sprang. That's generally not how evolution works as it presents a chicken/egg problem.

Additionally, I'm sure I've read that it is routine for microbes to absorb other microbes of the same or different species, and even steal their cell organs for their own use.

 

[Vertigo]

I suspect there's a misunderstanding about this in general, and that we're more likely looking at a wider population event rather than an individual event. In other words, that multiple instances could have happened at the same time, and that all later populations of eukaryotes evolved from these.

Additionally, when primary endosymbiosis happens, the newly formed organ loses it's own genetic diversity over time. So I would have thought it's actually impossible to define it as a single event involving one individual, as opposed to a population change.

Otherwise IMO looking for a single individual LECU or LUCA or similar is like assuming that once there were no humans and there was suddenly one, from which all humans sprang. That's generally not how evolution works as it presents a chicken/egg problem.

Additionally, I'm sure I've read that it is routine for microbes to absorb other microbes of the same or different species, and even steal their cell organs for their own use.

I'm pretty sure it's only the mitochondria that lost or gave up most of it's genetic data I don't believe the host cell did. Also if it was multiple cases of primary endosymbiosis then I would expect each to be very different based on different prokaryotes.