Life may be 9 billion years old

[cosmicalstorm]

I just finished reading this newly published paper. I think it has some theories about the origin of life, the Fermi Paradox, a pretty sober take on the idea of technological singularity and the future of technology in general. The main argument is that you can use Moore's Law to backtrace the age of life, dating the emergence of the first replicators to a time several billion years before the solar system condensed. I'm not qualified enough to state if it makes any seriously testable predictions but I do believe it makes some.

http://arxiv.org/abs/1304.3381

An extrapolation of the genetic complexity of organisms to earlier times suggests that life began before the Earth was formed. Life may have started from systems with single heritable elements that are functionally equivalent to a nucleotide. The genetic complexity, roughly measured by the number of non-redundant functional nucleotides, is expected to have grown exponentially due to several positive feedback factors: gene cooperation, duplication of genes with their subsequent specialization, and emergence of novel functional niches associated with existing genes. Linear regression of genetic complexity on a log scale extrapolated back to just one base pair suggests the time of the origin of life 9.7 billion years ago. This cosmic time scale for the evolution of life has important consequences: life took ca. 5 billion years to reach the complexity of bacteria; the environments in which life originated and evolved to the prokaryote stage may have been quite different from those envisaged on Earth; there was no intelligent life in our universe prior to the origin of Earth, thus Earth could not have been deliberately seeded with life by intelligent aliens; Earth was seeded by panspermia; experimental replication of the origin of life from scratch may have to emulate many cumulative rare events; and the Drake equation for guesstimating the number of civilizations in the universe is likely wrong, as intelligent life has just begun appearing in our universe. Evolution of advanced organisms has accelerated via development of additional information-processing systems: epigenetic memory, primitive mind, multicellular brain, language, books, computers, and Internet. As a result the doubling time of complexity has reached ca. 20 years. Finally, we discuss the issue of the predicted technological singularity and give a biosemiotics perspective on the increase of complexity.

http://io9.com/moores-law-predicts-life ... -476129496

A new study co-authored by a geneticist at the National Institutes of Health concludes that life originated elsewhere in the Universe around 9.8 billion years ago – roughly five-billion years before the Earth was even formed. But how did the study arrive at this conclusion, and does it make any sense?

Life Before Earth

The study, conducted by NIH geneticist Alexei Sharov and theoretical biologist Richard Gordon, operates on a number of assumptions, but here's the big one: life adheres to something resembling Moore's Law, increasing in complexity over time at an ever-accelerating rate. By tracing the thread of genetic complexity back in time, the researchers argue, one can estimate when life originated

Moore's Law, specifically, states that computer performance will double every 18 months, giving rise to an exponential increase in technological complexity. This not only enables us to speculate about the capabilities of future tech, it also allows us to track computer performance back through time and arrive at when that technology first began. In the case of Moore's Law's application to the exponential increase of transistors on integrated circuits, this corresponds to the 1960s, when said number was... well... zero.

In a paper recently posted to the preprint database arXiv, Sharov and Gordon suggest that the origin of life can be estimated by examining genetic complexity through the lens of Moore's Law and backtracking to some point of temporal origin. By tracing the course of evolution over the last several eons – beginning with single-celled organisms and working up through increasingly complex species like fish and mammals – the researchers ultimately conclude that genome complexity has increased exponentially by doubling, not every 18 months as seen with Moore's Law, but every 376-million years.

"What is most interesting in this relationship," the researchers write "is that it can be extrapolated back to the origin of life. Genome complexity reaches zero, which corresponds to just one base pair, at time ca. 9.7 billion years ago... ±2.5 billion years."

Earth is on the order of just 4.5-billion years old. Ipso facto, say the researchers, life originated somewhere besides Earth, evolving not on a geologic time scale, but a cosmic one.

Think that's wild? It gets weirder. Sharov and Gordon go on to draw connections to panspermia, the seeding of life by intelligent aliens, the failures of the Drake equation, and more:

This cosmic time scale for the evolution of life has important consequences: life took ca. 5 billion years to reach the complexity of bacteria; the environments in which life originated and evolved to the prokaryote stage may have been quite different from those envisaged on Earth; there was no intelligent life in our universe prior to the origin of Earth, thus Earth could not have been deliberately seeded with life by intelligent aliens; Earth was seeded by panspermia; experimental replication of the origin of life from scratch may have to emulate many cumulative rare events; and the Drake equation for guesstimating the number of civilizations in the universe is likely wrong, as intelligent life has just begun appearing in our universe.
What You Should Take Away

Look. This is a fun study. It's literally speculating on the origins of life itself – which, from an existential, cosmological, philosophical, religious, exobiological, and countless other perspectives, is kind of a big deal. Maybe the biggest deal. There's talk of panspermia, and aliens, and there's implications for life on other worlds throughout the Universe. It's all quite sexy and fun and interesting. But here's the big upshot, the one that you should keep in mind at all times: biological complexity is a remarkably complex subject.

One thing that worries me about this paper is that it makes no effort, as far as I can tell, to distinguish between complexity and progress, an important distinction that many people fail to recognize. Evolution has no aim, no directionality, no aspirations to "improve." Organisms have been shown to evolve to become more "complex," and they've been shown to evolve to become "simpler" (more on the use of quotation marks in a moment), but never in order to become better, by any objective sense of the word. And while most people who've thought about it probably recognize that complexity does not imply progress or improvement, one of the most common misconceptions about evolution is that it drives organisms toward some sort of ideal. A paper that hinges so fundamentally on a discussion of biological complexity would do well to acknowledge this non-sequitur in a prominent and unambiguous way.

Another issue: the idea that the complexity of life on Earth has increased at the same rate throughout history is highly suspect. The researchers acknowledge this themselves, writing that "there is no consensus among biologists on the question how variable are the rates of evolution." A popular hypothesis in biology known as Punctuated Equilibrium maintains that major evolutionary changes occur during short intervals, interspersed throughout long periods of relative stability. Sharov and Gordon concur that evolutionary rates fluctuate in time, but "strongly disagree" that punctuated equilibrium makes rates of evolution so unstable as to make "any extrapolation of them into the past... meaningless." They disagree so strongly, in fact, that they claim attempts to restrict "the presumed origin of life" to Earth with drastically fluctuating rates of evolution "are strikingly similar to stretching and shrinking of time scales in Biblical Genesis to fit preconceptions." Please.But the most important takeaway of all – one remarked upon by several peer-reviewed papers on the subject of biological complexity in recent years – is how little consensus there is on what complexity actually is. An excerpt from this 2002 review by Cal Tech's Christoph Adami, a renowned evolutionary theorist and nuclear physicist, summarizes the situation thusly:

Arguments for or against a trend in the evolution of complexity are weakened by the lack of an unambiguous definition of complexity. Such definitions abound for both dynamical systems and biological organisms, but have drawbacks of either a conceptual or a practical nature.
Another excerpt, taken from an article published in Nature in 2008, paints a similar picture of confusion:

In his book Programming the Universe, engineer Seth Lloyd of the Massachusetts Institute of Technology in Cambridge describes how he once compiled 42 definitions of complexity — none of which encompasses everything people mean by that word.
Biological complexity can be defined by cell number, cell type, body plans, gene content, or – in the case of the Sharov and Gordon's work – genomic complexity, "roughly measured by the number of non-redundant functional nucleotides." It can be defined by other things as well. In this sense, Sharov and Gordon's description of complexity as having been "roughly measured," seems rather apt. This study is a fascinating thought experiment, but it – and science's understanding of biological complexity in general – lacks the rigorous definitions necessary for a firm evolutionary hypothesis.

Images via Shutterstock; Log scale of genome size over time via Sharov and Gordon

[SilverWingedSeraph]

It's garbage.

[Dr. Trainwreck]

Seriously, beyond the crappity crap this article is, how the hell can one calculate a biological equivalent of Moore's Law? And just how complete does the fossil record have to be?

Somebody might as well take this to SLAM, assuming it's not locked anyway.

[Simon_Jester]

They're trying to apply a smooth curve-fit to data which defy measurement, let alone accurate measurement, then project that backwards into time.

This is roughly as stupid as saying "my house was struck by lightning in 1994 and again in 2004, therefore it will be struck by lightning again in 2014."

[Omeganian]

Accurate to within an order of magnitude? Not bad.

[Ziggy Stardust]

They're trying to apply a smooth curve-fit to data which defy measurement, let alone accurate measurement, then project that backwards into time.

This is roughly as stupid as saying "my house was struck by lightning in 1994 and again in 2004, therefore it will be struck by lightning again in 2014."

This is roughly why anytime you hear someone like Ray Kurzweil talk about "technological singularity" you know they are a fucking moron. I mean, you can come to any conclusion you want if you cherry-pick data to fit to a curve and then extrapolate based on that.



EDIT: I mean, fuck, this sentence ALONE demonstrates that these people are pulling this out of their asses: "Linear regression of genetic complexity on a log scale extrapolated back to just one base pair ..." Always be suspicious of extrapolated log scales, they are a wonderful tool for people to use to "prove" relationships that don't exist.

[Simon_Jester]

The trick is to recognize the cutoff points. For example, the cutoff point in Moore's Law is likely to show up when we reach the limit on how small we can miniaturize an integrated circuit- getting past that point will take a breakthrough in theory, not practice, and one which Moore's Law cannot predict.

Likewise, the minimum genetic complexity of an organism is probably N thousand base pairs, and any curve-fit to the complexity of organisms probably has to stop at N thousand base pairs. The human genome contains about 3.2 billion base pairs, so... hm.

Now, we might extrapolate from the curve we're faced and the known span of existence of life on Earth, that... [does math with logarithms in]... five hundred thousand base pairs. The simplest known bacteria actually have 150 thousand, so that doesn't sound too impressive- we're positing that the earliest known bacteria had genomes three times longer than some which are alive today.

[Feil]

Some advice for the future.

When you encounter a paper or a news article about a scientific study, follow the following process.

1: If it's in a news article, and it seems interesting, immediately ignore everything the news article says, look up the original paper (or at least its abstract), and read the abstract. Even if you only have a high school science education, you're better off doing this, because the person who wrote the news article isn't any better qualified than you AND they're trying to sell copies or pageviews, so they have an incentive to sensationalize. For instance, every year or so, some otherwise reputable mainstream news outlet falsely reports that scientists have disproved Relativity. Simply glancing over the abstract of the study referenced is usually enough to figure out if the news article and the scientific paper actually say the same thing.

2: Before you read past the abstract, find out if the paper is published in a peer-reviewed scientific journal. Alas, there is no "OFFICIALLY PEER-REVIEWED" stamp, so do this by finding out who published it, then looking up that publisher. If it isn't, ignore both the news article and the paper, and get on with your life, because if it's not peer-reviewed, there's probably a reason.

3: If it is peer-reviewed, read the abstract and introduction, skim the body and the diagrams, and read the conclusion. Pay close attention to qualifiers on the results, margins of error, etc.

[Dalton]

Moved this to SLAM.

[The Xeelee]

Even if their theory was accurate, this would be off due to natural disasters and the like surely?

[Dr. Trainwreck]

They say give or take 2.5 billion years. This is an error margin that is close to 13% the age of the universe. Guess there are things for which there is no reliable estimate.

[Singular Intellect]

This is roughly why anytime you hear someone like Ray Kurzweil talk about "technological singularity" you know they are a fucking moron. I mean, you can come to any conclusion you want if you cherry-pick data to fit to a curve and then extrapolate based on that.

Except Kurzweil has dealt with this claim on multiple occasions and even has had numerous experts submit their own independent data sets and demonstrated how they still yield exponential curves of progress.

However, that would require an honest review and actual understanding of Kurzweil's arguments and positions. Ergo, I understand your temptation to just lie about his position, not investigate if he's addressed a specific criticism and then just appeal to personal incredulity about his conclusions.

If you're going to criticize Kurzweil's position and arguments, by all means feel free to do so. Just don't submit an objection that is the hilarious equivalent of a theist who thinks they're proposing a clever god argument when it's one that has been addressed and shut down countless times already.

[Zinegata]

As a rule of thumb, anyone who predicts "Technological SIngularity" is just spouting unfalsifiable horseshit on the same level as force-fitting Nostradamus "predictions". Kurzweil belongs to this category.

[Straha]

Prepare for a partial thread hijack, but I think the data does pose an interesting thought experiment, namely backward projection and understanding of development and an attempt to understand the past through the present.

One of the interesting thoughts I've been toying with, and it's explored (if only tangentially, briefly, and in a most unsatisfying way) by the paper here. I think that there's ample ground for a reverse Fermi's Paradox. If we take for granted that humans are an evolutionary product, and nothing more, and that intelligence is favored, if only partially, by evolution then it makes no sense for humans to be the only intelligent species to have evolved on Earth. The biological span that it has taken to develop the distinctly homo sapiens species is negligible in face of the grand history of Earth, and the noted biological diversity found throughout Earth's history. Humans have gone from negligible 'development' to space flight in a time frame measured in millenia, an eye-blink of the world. So the question: Where are the other terrestrial 'intelligent' species who developed and passed away? Is there evidence to be found of their existence or has it been destroyed in the (tens of) millions of years that have passed since their existence? Did they explore space and we just haven't found the evidence/mistake it for natural geological development? Or is there something else afoot that we don't realize?


Or maybe this is a better short story. Apollo 19 lands on the moon and finds a lander built and designed for reptilians, and a bronze plaque of the Earth as it was ninety million years ago.

[madd0ct0r]

that is fermi's paradox. no need to add 'reverse' to it.

A truly reversed fermi paradox would be life everywhere, communicating happily when there's no intelligent observer to note it (a paradox in itself)

[Straha]

that is fermi's paradox. no need to add 'reverse' to it.

A truly reversed fermi paradox would be life everywhere, communicating happily when there's no intelligent observer to note it (a paradox in itself)

Not quite.

Fermi's paradox is that if the drake equation holds true the universe should be teeming with intelligent* extraterrestrial life and we should see signs of them, so where are they? That's an interesting question but, for a variety of reasons, irrelevant to my concerns**.

My question is to reverse the focus of the Paradox. Given how quickly intelligent life develops and the apparent evolutionary advantages of intelligent life: where's the sign of intelligent life on Earth prior to humans? Surely intelligent life has developed on Earth in its history, probably multiple times before humans sprang onto the scene. So where are the signs that they existed?



*I use the term intelligent colloquially, and in a way I personally disagree with solely to further the conversation in the quickest possible way.

** For example, I think the question of intelligibility renders the possibility of recognizing, much less understanding, alien communication moot. The rare Earth hypothesis also poses a considerable problem here. With regards to my question both these issues should be mitigated or irrelevant, respectively.

[Formless]

Your paradox is non-existent. Hominids already fill the niche of pre-human intelligence. We have plenty of evidence for their intelligence, such as the tools they left behind and in some cases (the Neanderthals) more than that. Of course, the only hominid still standing is Homo Sapiens, and that may not be a coincidence. Species often evolve into exclusive ecological or morphological niches, because competition tends to drive out all but the most well adapted form.

Thing is, 1) you are misrepresenting what the Drake equation is 2) the Drake equation doesn't work in the context of a single planet by design. We know for a fact just how little time multi-cellular lifeforms have existed for on Earth, let alone the animal kingdom. Hell, we can even pinpoint when specific adaptations took place like the evolution of the eye. The Drake equation doesn't have an input for time, but this would be like being able to say with precision just how many planets undergo abiogenesis, how many go onto develop intelligence, and precisely how many were able to leave evidence of their own existence. The Drake equation is a set of variables, not something with a computed value like the equations of General Relativity. Fermi's paradox is one of epistemology, so the instant you are actually able to gather the data the paradox resolves.

Besides which, your reasoning seems to assume intelligence happens spontaneously. In fact, the instant you say its an "evolved" trait you concede that the functions of intelligence built upon previous adaptions, which in turn were built upon previous adaptations (ad nauseum). Which means that the obvious solution is that humans were not a sudden development at all, but rather the result of many adaptations and features reaching a critical mass. A "Singularity" if you will. It could happen again (maybe), but there is no reason to believe it could have happened prior. And this conclusion requires no Moore's Law horseshit.

[LaCroix]

Besides which, your reasoning seems to assume intelligence happens spontaneously. In fact, the instant you say its an "evolved" trait you concede that the functions of intelligence built upon previous adaptions, which in turn were built upon previous adaptations (ad nauseum). Which means that the obvious solution is that humans were not a sudden development at all, but rather the result of many adaptations and features reaching a critical mass. A "Singularity" if you will. It could happen again (maybe), but there is no reason to believe it could have happened prior. And this conclusion requires no Moore's Law horseshit.

It has - we have multiple non-primate species on this planet that show tool usage. Given that we took about 4 million years to evolve from australopithecus to the "technological explosion" of bronze age till now, we might very well see stone-age technology reemerge in a million of years (If we don't fuck this planet up too much...)

[Straha]

Your paradox is non-existent. Hominids already fill the niche of pre-human intelligence. We have plenty of evidence for their intelligence, such as the tools they left behind and in some cases (the Neanderthals) more than that. Of course, the only hominid still standing is Homo Sapiens, and that may not be a coincidence. Species often evolve into exclusive ecological or morphological niches, because competition tends to drive out all but the most well adapted form.

This is the sort of answer that has its head so far up the ass of anthropocentrism that it loses all perspective. Hominids have tool using intelligence, that's fine but I think irrelevant. In the grand scheme of things we're part of that hereditary group and thus I lump their experiences, or at least 'our' direct ancestors' experiences, in with 'our' experiences. What you're missing is that that hominid line took about four million years to get to this point (in fact I think it took far shorter, we can see all sorts of examples of non-human tool building and language use in contemporary species. The question, I think, is the development of the cultural, dare I say memetic, passing on of the skills of tool, in which case the distinction I'm probing here is not biological but social and dates back in the tens of thousands of years.), in the biological history of Earth that goes back 500 millions that's nothing. Why didn't other species to develop?

Or, let me boil this down even more. Hominids have developed for 60 million years (give or take) since the K-T event essentially reset most biological life on Earth. The Mesozoic period, by contrast, saw roughly 150 million to 200 million years of more or less stable development of life after the Permian-Triassic extinction event until the K-T event. Given our contemporaries it's fair to say that at least a degree of intelligence, communication, and tool use must have existed. So why do we not have evidence of a dominantly intelligent species during the Mesozoic period? Nothing in your answer touches on this.

Besides which, your reasoning seems to assume intelligence happens spontaneously. In fact, the instant you say its an "evolved" trait you concede that the functions of intelligence built upon previous adaptions, which in turn were built upon previous adaptations (ad nauseum). Which means that the obvious solution is that humans were not a sudden development at all, but rather the result of many adaptations and features reaching a critical mass. A "Singularity" if you will. It could happen again (maybe), but there is no reason to believe it could have happened prior. And this conclusion requires no Moore's Law horseshit.

I'm curious where you possibly get the idea that A. I discount the work of previous generations and/or B. like the Hegelian progressivist mysticism that is Moore's law. If life has existed for three hundred to four hundred million years I think it is the height of human exceptionalism to say that the sort of accrual of skills and knowledge that has led to modern hominids and humans could have occurred in recent history.

More accurately I'm saying that your statement that "there is no reason to believe it could have happened prior" is a warrantless assertion. There's no reason to believe it couldn't have happened in the Mesozoic Era, or earlier. The climate was stable, there was certainly enough competitive impetus, braid development had occurred and we know from nesting sites that was social interaction throughout most of the time frame. The foundation is there, along with the timeframe necessary for development to occur many times over. Given that it'd require very strong evidence to prove to me it didn't happen, so why don't we have evidence of it?

[Guardsman Bass]

So the question: Where are the other terrestrial 'intelligent' species who developed and passed away? Is there evidence to be found of their existence or has it been destroyed in the (tens of) millions of years that have passed since their existence? Did they explore space and we just haven't found the evidence/mistake it for natural geological development? Or is there something else afoot that we don't realize?

Certain materials might survive in the sedimentary rock layers from that time period if a Mesozoic civilization advanced far enough technologically to make them. Plastics take extremely long to decay, and if they were buried properly, you might be able to find traces of them in the rocks. If you were fortunate (and the Mesozoic species unfortunate) enough to get a Pompeii-style event where a city was completely drowned in ash which then hardened into rocks/fossils, it might show up as a very unusually organized area of fossilization.

Other than that, I'm not sure. The massive coal layers dated to the Carboniferous Forest Collapse do not appear to have been tapped in any significant way before the rise of human coal extraction, which means that a hypothetical Mesozoic civilization either never got that far technologically speaking, mostly utilized other resources, or largely skipped the use of coal extraction on an industrial scale. I find the last one hard to believe for any industrial civilization, since you use a lot of coal for coke if you want to produce steel.

Or maybe this is a better short story. Apollo 19 lands on the moon and finds a lander built and designed for reptilians, and a bronze plaque of the Earth as it was ninety million years ago.

That would be awesome as a story.

As for the Drake Equation, who knows. I'm inclined to think that tool-using civilizations are scattered enough in time and space so that any contact between them is extremely unlikely, particularly since trying to find them by radio emissions is like searching for the proverbial needle, and interstellar travel is an extremely expensive trade-off between spending tons of energy and building super-complicated machines that can work for centuries in interstellar space. But that's purely speculative on my part.

[Guardsman Bass]

Sorry, edit time expired-

If an intelligent Mesozoic species had anything like the spread and impact of humanity on its environment even at a relatively low technological state compared to us (such as the equivalent of 2000 BCE, for example), I think it would be very strange not to see it in the fossil record. Just compare how many skeletons we find of Allosaurus individuals, another highly common dinosaur species. But so far, we haven't found any finds from the Mesozoic that would hint at advanced brain size or development, or exceptionally complex societal organization.

[Algebraist]

I think the answer to this is already alluded to earlier in the thread. There is no inevitable arrow of evolution, only a whole load of random genetic mutations where the benefical ones are usually selected for it that organism survives to breed (it only increases the likelihood). Thus the exponential extrapolation of complexity and evolutionary advance is rather meaningless.

Certain events in the evolution of mammals can have advanced intelligence, there is no guarantee that similar steps would occurr on a different line or at any where near the same pace.

[Formless]

I think the answer to this is already alluded to earlier in the thread. There is no inevitable arrow of evolution, only a whole load of random genetic mutations where the benefical ones are usually selected for it that organism survives to breed (it only increases the likelihood). Thus the exponential extrapolation of complexity and evolutionary advance is rather meaningless.

Certain events in the evolution of mammals can have advanced intelligence, there is no guarantee that similar steps would occurr on a different line or at any where near the same pace.

This. Straha's pleas of "anthropocentrism" shows he is just trolling (I mean, he did skip the meat of my post, and he misinterpreted my allusion to the OP as directed at himself so he can cry foul), or else doesn't understand the sciences at work here. There is nothing in our scientific theories or data that makes his speculations worthy of consideration-- no mysterious data points to require a hypothesis, no inconsistencies that would make make it more parsimonious than a planet where only hominids developed higher intelligence. In fact, the paleontological record is complete enough that its worthwhile to invoke "absence of evidence is evidence of absence", and leave it at that. Unless, of course, we are talking about our own ancestry, in which case there is no analogy to Fermi's paradox because we have already found evidence of other intelligences.

I suspect this is just one of those exercises where he tries to paint his opposition as somehow biased, even when that flies in the face of what his opponents have said. In this case, I stated at the end that an intelligence event could happen again (as the niche-locking hypothesis has not been proven for intelligence), a concession that the only thing making hominids special is their place in time. And if you take the Drake equation at the cosmic scales that it was intended to apply to, then yes humans arguably shouldn't be special, except insofar as we haven't found any of the civilizations that one would expect to find out there (hence Fermi's paradox). But the paradox stems from lack of data and the scale of the universe as much as it does from time. Straha is stuck on the time aspect, and completely ignoring the fac

[Formless]

Fuck, the edit function just shat on my post somehow. Here's the part that got deleted:

[...] But the paradox stems from lack of data and the scale of the universe as much as it does from time. Straha is stuck on the time aspect, and completely ignoring the factors of scale and data.

Put it another way, lets take his ideas and put them back onto a cosmic scale: taking the set of all planets where intelligent life arose, what should we expect is the average number of intelligent species that arose on those planets? One, or more than one? For fairness, lets discount the fact that evolution necessitates ancestral forms so that we're counting all branches of the hominid genus, and not homo sapiens only. Given that our data is constrained to just one planet, it is not unreasonable to assume an average of one like our own. This may not be true, but its does not break parsimony either when that is the data set. Additionally, we can take the evolutionary trend of niche-locking as evidence that it should be the norm, albeit not hard evidence either. And there is the fact that as quickly in geologic terms the hominid line evolved, the technology and civilization of our specific species evolved an order of magnitude faster still, which would tend to globalize any sort of niche-locking effect rather than keeping it contained to a single geographic location as normally happens in evolution. Like LaCroix pointed out, we may yet fuck this planet's ecosystem up enough that no further intelligence events can happen anymore.

For the record, I have always believed that the Fermi paradox is actually due to our own impatience with observation rather than a genuine inconsistency between expectation and observation. Our search for extrasolar planets alone (the first damn variable of the Drake equation) has only been done in earnest for a couple decades, and our search for civilizations has been so half assed it really shouldn't be a surprise we haven't found anything. These things take time and effort, no shit?

[Simon_Jester]

Prepare for a partial thread hijack, but I think the data does pose an interesting thought experiment, namely backward projection and understanding of development and an attempt to understand the past through the present.

One of the interesting thoughts I've been toying with, and it's explored (if only tangentially, briefly, and in a most unsatisfying way) by the paper here. I think that there's ample ground for a reverse Fermi's Paradox. If we take for granted that humans are an evolutionary product, and nothing more, and that intelligence is favored, if only partially, by evolution then it makes no sense for humans to be the only intelligent species to have evolved on Earth. The biological span that it has taken to develop the distinctly homo sapiens species is negligible in face of the grand history of Earth, and the noted biological diversity found throughout Earth's history. Humans have gone from negligible 'development' to space flight in a time frame measured in millenia, an eye-blink of the world. So the question: Where are the other terrestrial 'intelligent' species who developed and passed away? Is there evidence to be found of their existence or has it been destroyed in the (tens of) millions of years that have passed since their existence? Did they explore space and we just haven't found the evidence/mistake it for natural geological development? Or is there something else afoot that we don't realize?

Key possibilities:

1) We may be overestimating how easy it is to detect the evidence of civilizations that existed tens of millions of years ago.

2) We may be overestimating the importance of tool use, as opposed to intelligence. Humans evolved intelligence and tool use together; we needed tools because we are physically weak relative to the ecological niche our simian ancestors tried to occupy. Tool use gave us an edge we couldn't duplicate by natural means.

But what about, say, elephants? It is often speculated that elephants might be intelligent; they are relatively social animals, with complex behavior patterns, and some behaviors we otherwise only see around humans, such as 'funeral' practices. Elephants could well profit from intelligence (it makes them tougher targets than if they were solitary animals like the rhinoceros, and probably helps them keep track of social dynamics within the herd). But they don't benefit much from tool use, because they already have vast physical strength and toughness. Plus, unlike simians they don't have any body parts that could easily evolve into delicate tool-wielding members as the human hand did.

For all we know, elephants, whales, and a few other such species in the planet's history have been intelligent and it doesn't show in terms of permanent construction or toolmaking that might survive in the fossil record.

It has - we have multiple non-primate species on this planet that show tool usage. Given that we took about 4 million years to evolve from australopithecus to the "technological explosion" of bronze age till now, we might very well see stone-age technology reemerge in a million of years (If we don't fuck this planet up too much...)

Or not- tool use may have been around much longer than that, and we just haven't found the evidence because a monkey who picked up a sharp rock 20 million years ago leaves no evidence distinct from what we'd see anyway.

The jump to full tool use, I think, relies on a combination of two evolutionary pressures at once. On the one hand you need a creature that already has great intelligence and manual dexterity, because otherwise it won't start using tools no matter what: cows aren't going to evolve tool use any time soon. On the other hand, you also need the creature to be physically inadequate for purposes of coping with some threat in its environment: it has to profit from using sharp rocks instead of teeth and claws, or from using furs and fire for warmth, or something of that order.

Chimpanzees may be roughly as intelligent as ramapithecines, but it is NOT a foregone conclusion that they'll evolve a tool-using subspecies in a few million years if given the opportunity. Not if they're strong enough and physically equipped enough that they can do without the tools.

The question, I think, is the development of the cultural, dare I say memetic, passing on of the skills of tool, in which case the distinction I'm probing here is not biological but social and dates back in the tens of thousands of years.), in the biological history of Earth that goes back 500 millions that's nothing. Why didn't other species to develop?

Lack of the right combination of need and biological equipment? Dinosaurs, by virtue of being totally different in terms of metabolism, ecological role, and so on, would not feel the same evolutionary pressure to develop intelligence AND advanced tool use. Or might not. Likewise for, say, wolves. Or dolphins. Or other relatively smart animals who we might call 'candidates' as the potential ancestors of a fellow intelligent species.

I'm curious where you possibly get the idea that A. I discount the work of previous generations and/or B. like the Hegelian progressivist mysticism that is Moore's law. If life has existed for three hundred to four hundred million years I think it is the height of human exceptionalism to say that the sort of accrual of skills and knowledge that has led to modern hominids and humans could have occurred in recent history.

Flowering plants didn't evolve into the Cretaceous. Why? No obvious reason.

Multicelled life didn't evolve for four billion years. Why? No obvious reason; there was enough oxygen in the air and everything for a LONG time.

The fossil record is full of major evolutionary shifts that simply don't "happen to happen" until randomness and climate change and biological precursors are in place to make them possible. We may have a lot of information, but we have a staggering amount of ignorance about those preconditions, because we can't observe any of these organisms in their living habitat to understand the context of their existence.

More accurately I'm saying that your statement that "there is no reason to believe it could have happened prior" is a warrantless assertion. There's no reason to believe it couldn't have happened in the Mesozoic Era, or earlier. The climate was stable, there was certainly enough competitive impetus, braid development had occurred and we know from nesting sites that was social interaction throughout most of the time frame. The foundation is there, along with the timeframe necessary for development to occur many times over. Given that it'd require very strong evidence to prove to me it didn't happen, so why don't we have evidence of it?

Maybe you expect the evidence to be more visible than it really is.