Catch up on stories from the past week (and beyond) at the Slashdot story archive

 



Forgot your password?
typodupeerror
×
Science

Moore's Law and the Origin of Life 272

DoctorBit writes "MIT Technology Review is running a story about an arXiv paper in which geneticists Alexei A. Sharov and Richard Gordon propose that life as we know it originated 9.7 billion years ago. The researchers estimated the genetic complexity of phyla in the paleontological record by counting the number of non-redundant functional nucleotides in typical genomes of modern day descendants of each phylum. When plotting genetic complexity against time, the researchers found that genetic complexity increases exponentially, just as with Moore's law, but with a doubling rate of about once every 376 million years. Extrapolating backwards, the researchers estimate that life began about 4 billion years after the universe formed and evolved the first bacteria just before the Earth was formed. One might image that the supernova debris that formed the early solar system could have included bacteria-bearing chunks of rock from doomed planets circling supernova progenitor stars. If true, this retro-prediction has some interesting consequences in partly resolving the Fermi Paradox. Another interesting consequence for those attempting to recreate life's origins in a lab: bacteria may have evolved under conditions very different from those on earth."
This discussion has been archived. No new comments can be posted.

Moore's Law and the Origin of Life

Comments Filter:
  • No. (Score:4, Interesting)

    by ljhiller ( 40044 ) on Tuesday April 16, 2013 @12:59PM (#43464167)
    " If true, this retro-prediction has some interesting consequences in partly resolving the Fermi Paradox."

    A single base pair is not alive, not even in a primitive way. The extrapolation is invalid. A more interesting statement would be the minimum complexity of the first living things 3.5-4.0 billion years ago.

    • As anyone who is familiar with interpolation knows, extrapolation is a very risky business that provides little statistical confidence and error bounds in the prediction.

      Of course, that doesn't prevents some from trying to use it to win the lottery anyway. Sure you get a prediction, but there is virtually no way to assign useful error bounds to the prediction.

    • > partly resolving the Fermi Paradox

      Another problem not even mention is that the Fermi Paradox is based on lack of information; it is a pseudo Paradox become people don't understand all the variables. In 10 years this paradox will become moot as new information is made available on a new discovery.

      --
      Science is not about a path towards Truth, but a path of removing ignorance.

  • by Anonymous Coward on Tuesday April 16, 2013 @12:59PM (#43464169)

    This is a fine example of how not to use arXiv as a news source. This old yarn has been trotted out before, and it is based on bad assumptions about complexity and offers a handy False Dilemma Fallacy.

    Either
    1+1=6 or
    1+1=8.
    1+1=6 is disproved, so 1+1 =8!

    Or your math is wrong.
    Complexity != genome size.
    See c-value enigma.

    • This is a fine example of how not to use arXiv as a news source.

      You don't understand what peer review is about. Peer review doesn't guarantee that a paper is true or even reasonable. Peer review, in general, just says that a paper is of sufficient interest to be published.

      and it is based on bad assumptions about complexity and offers a handy False Dilemma Fallacy.

      The paper doesn't make any "assumptions" about complexity, nor does it pose a "dilemma". It just measures a number associated with genomes and ex

      • This paper wouldn't pass peer review (at least in any not-completely-flaky-pseudodcience-field; there's probably a "genetic semiotics and wild-ass futurism" journal where this would fit right in). One key thing that immediately entirely disqualifies it: there is absolutely no discussion of how/why they selected the six data point categories on their main plot ("prokaryotes," "eukaryotes," "worms," "fish," and "mammals"), or even what the points specifically refer to (what the hell are "worms"? there's a doz

        • One key thing that immediately entirely disqualifies it: there is absolutely no discussion of how/why they selected the six data point categories on their main plot

          There is a reference to a published paper that explains it, which is the way this sort of thing works in the sciences.

          I'm not defending the paper (there are lots of things wrong with it), but both "anonymous" and you seem to be having real trouble reading scientific papers and understanding peer review.

          • Ahh, I see, a reference to the author's own previous paper, in which he says basically the same stuff with a bit more detail. I like that the journal this one is published in shows the "open peer review" criticisms of the paper, including this statement from the second reviewer which neatly sums up the issues:

            This paper is an example of how not to analyze data.

    • This is a fine example of how not to use arXiv as a news source. This old yarn has been trotted out before, and it is based on bad assumptions about complexity and offers a handy False Dilemma Fallacy.

      Either 1+1=6 or 1+1=8. 1+1=6 is disproved, so 1+1 =8!

      Or your math is wrong. Complexity != genome size. See c-value enigma.

      Is "so 1+1 =8!" meant to be read as: "so one plus one equals eight... NOT"?

  • oblig xkcd (Score:5, Funny)

    by Anonymous Coward on Tuesday April 16, 2013 @01:04PM (#43464219)

    http://xkcd.com/605/

  • by MetalliQaZ ( 539913 ) on Tuesday April 16, 2013 @01:05PM (#43464229)

    All of this assumes that the complexity of life, as he defines it, increases at a relatively constant rate. There is no reason that this has to be true. Environmental effects on organisms increases selective pressure and causes evolution to progress at a faster rate. Cataclysmic events happen every now and then and causes extinctions and hardship on surviving organisms. Seems pretty uneven to me...

    • by ThorGod ( 456163 ) on Tuesday April 16, 2013 @01:19PM (#43464385) Journal

      You said it better than I was going to say it.

      The way I see it, they:
      a.) Plotted some data
      b.) Extrapolated a simple trend from that data
      c.) Forecasted, using the trend function, before the point of data collection
      d.) Came up with some wild conclusions from that forecast (or "beforecast"?) that rely heavily on the validity of the simple trend.

      It kind of smells like bad science...or at least risky science.

      • What's wrong with connecting dots? We project the past into the future routinely and reliably. Why can't it run backwards? Epidemiologists certainly do that. Consider today's cinema ... audience sizes, production cost, production values, censorship, graphic content, crew size, number of awards. It scarcely matters which parameters are picked as long as they can be measured. Next, examine those parameters for the 1990s, 1970s, and 1950s. From those data points, you can infer trends. From those trends, y
        • What's wrong with connecting dots?

          Well, for one thing, there's zero explanation of why/how they chose the particular dots they connected (or even precisely what they refer to), other than "hey, if we cherry-pick these particular 6 points, they lie on a line that proves our hypothesis!".

        • Re: (Score:2, Insightful)

          by Anonymous Coward

          Here's the problem: reasonable functions exist which behave completely differently from what goes on inside the data set.

          Let's take the article before us as an example. If x(t) is the average number of functional base pairs in an organism as a function of time, the article's authors are asserting that x'(t) = kx(t), or rather that the rate at which more base pairs are generated is proportional to the existing amount of base pairs.

          But what if we change this just a tiny bit? What if x'(t) = kx(t) + C, where C

    • by Kjella ( 173770 )

      All of this assumes that the complexity of life, as he defines it, increases at a relatively constant rate. There is no reason that this has to be true. Environmental effects on organisms increases selective pressure and causes evolution to progress at a faster rate. Cataclysmic events happen every now and then and causes extinctions and hardship on surviving organisms. Seems pretty uneven to me...

      All that aside, is there even a good logical reason to think the bootstrapping has much to do with the later processes? In the beginning a single mutation to a primitive life form is a much bigger deal than to a large, complex organism. Many bacteria have a life span of 20 minutes, that's 25000+ generations in a year so big positive or negative mutations would spread like wildfire. Meanwhile us humans have a regeneration cycle of 20-30 years and being large, complex organisms most of us carry a ton of posit

    • Cambrian Explosion (Score:5, Insightful)

      by femtobyte ( 710429 ) on Tuesday April 16, 2013 @01:33PM (#43464523)

      The assumptions in the article are especially suspect, given the large number of quite well documented "explosions" of genetic diversity in Earth's history (see, e.g., the Cambrian Explosion [wikipedia.org] for the biggest example, though there are plenty of lesser events), where gigantic leaps in genetic diversity appeared over (geologically) short timescales. An extrapolation assuming a generally smooth growth rate is simply untenable.

    • by Okian Warrior ( 537106 ) on Tuesday April 16, 2013 @01:45PM (#43464655) Homepage Journal

      ... Cataclysmic events happen every now and then and causes extinctions and hardship on surviving organisms

      Indeed, it appears that periodic cataclysmic events are required in order to keep evolution going.

      We've seen several eras in Earth's history where life appears to "stagnate" at some level, proceeding with little-or-no change for long periods. The last of which was the "age of dinosaurs", which lasted 170 million years or so, depending on how you define the starting point. It ended with the Chicxulub impact.

      We also see numerous examples of species which are largely unevolved; for example, ants have been around for 120 million years and one species [americanscientist.org] of prehistoric ant is apparently still living in the Amazon. Coelacanths [wikipedia.org] have been around in their present form for about 400 million years.

      The overall impression is that life tends to "stagnate": once life evolves into an efficient survival mechanism, there's no pressure to evolve further. Evolution aims at being a better "fit" for the unchanging environment, but more complexity is simply not needed.

      This is why I believe the Drake equation [wikipedia.org] is overly optimistic. I think it omits the factor "fraction of star systems that experience occasional planetary meteor strikes". If we ever travel to another star, we're likely to find it teeming with life, but stagnated at some level.

      This may be one factor (of possibly several) that explains the Fermi paradox.

      The "doubling rate" identified in the article may be an artifact of Earth, and that's only if Genome complexity [fourmilab.ch] is even a reasonable measure to make. Lilies have 30x the genome size of humans - another explanation might be that genome complexity is related to genome size, which does not have much selection pressure. It's not a peer-reviewed paper.

      • ...another explanation might be that genome complexity is related to genome size, which does not have much selection pressure. It's not a peer-reviewed paper.

        To be clear, I mean to say "genome size is not related to species complexity". Genomic data may be complex simply because it's large and presents a large target for evolutionary change, but a large genome doesn't necessarily result in a complex organism.

      • by dargaud ( 518470 )
        Agreed. Also I don't think phenotype is very much related to genetic complexity. Before the 'Iced Earth' episode (not the band), life was basically stromatolites for 2 billions years. Then ice covered everything, keeping a few isolated pockets for a long time. This must have put a lot of selective pressure on those pockets of life. It must have been like extended development of /lib while not doing much on the main apps. Then when the ice melted there was all those varied building blocks available to use in
        • Similarly while the dinosaurs roamed the Earth the mammals were 'under the ice'; a lot of /lib changes, but no possibility to get big or more varied than your primitive rat because of the competition. Then once the big guys got wiped out all those ecological niches were available and filled out faster than one would expect from standard selection processes; simply because the genotype had lots of diversity already: it just needed to show in the phenotype and a few minor mutations did that.

          Nice metaphor ("under the ice").

          I like the explanation, where species have forced evolution to survive in a limited and changed environment, then fan out when new niches become available.

          I'm told that there are niches which aren't populated, such as birds making holes in trees for nests. (The niche is not populated everywhere.) This would neatly fit in with that explanation - the species doesn't *need* to fill new niches to survive, until some environment-limiting catastrophe puts pressure to evolve, then w

      • We've seen several eras in Earth's history where life appears to "stagnate" at some level, proceeding with little-or-no change for long periods. The last of which was the "age of dinosaurs", which lasted 170 million years or so, depending on how you define the starting point.

        Well that explains why we hardly saw anything interesting happen at all during the age of the... reptiles. [wikipedia.org] No real [wikipedia.org] change [wikipedia.org] at all [wikipedia.org]. Totally stagnant.

        Whoa whoa whoa, the drake equation deals with intelligence arising out of evolution. And you're arguing that there needs to be a rapid rate of evolution on a global scale to achieve intelligence? It doesn't quite work that way. Intelligence is not the goal of evolution. You don't build up a value of evolution points and exchange them for opposable thumbs and en

      • Well, the sun does move about the galaxy and complete an orbit about every ~220-250 million years. Realistically if there's some section of the galaxy where you're more likely to run into planet bashing meteors then all of the planets in the galaxy will pass through it over geologic time scales. Heck, maybe there's two such bands, roughly half a galaxy apart, and after we pass through three of them the complexity of life roughly doubles to compensate for these wild changes. So every ~370 million years we

    • Re: (Score:3, Interesting)

      by Anonymous Coward

      All of this assumes that the complexity of life, as he defines it, increases at a relatively constant rate.

      The paper merely states that given:
      1) Our current understanding of evolutionary rates,
      2) Our current understanding of the age of the earth,
      3) Our current understanding of the origin of life ...at least one of the above has serious flaws.

    • by jovius ( 974690 )

      Take this gem for example from the article:

      For example, the doubling time of the number of scientific publications from 1900 to 1960 was only 15 years (de Solla Price, 1971). Interestingly, extrapolating the exponential increase of scientific publications backwards gives us an estimated origin of science at 1710 which is the time of Isaac Newton.

      That's not the origin of science, but it coincides with the industrial revolution, which sparked a new range of philosophical thinking from economy to nature. Besides printing press was readily established at that time to spread the news. There has always been science at some level. The selected viewpoint has an effect to the origin.

    • by idji ( 984038 )
      Be skeptical, but don't just be cynical. The Fermi Problem [wikipedia.org] may apply here!
    • What you are getting at is entropy and unpredictable events. And those factors are always averaged out through a proper application of the Scientific Method by having a large enough sampling size, a control group and testing alternative hypotheses.

      The larger the scope of what is being studied, the more entropy and unpredictable events factor into the sample size required. And computer models are incredibly bad at accounting for entropy and unpredictable events. A computer model with a mesh element cou
    • by Livius ( 318358 )

      I find the idea extremely cool.

      Of course, there's no rationale of any sort for the assumptions, so it's not science.

      But still cool.

  • How about a label for the supposed graph points before Prokaryotes?

    Otherwise one might conclude that they are simply assuming these "precursors" in the absence of even enough evidence such that they have a name--because that's what "must" have been the case per the assumed paradigm.

  • by Algae_94 ( 2017070 ) on Tuesday April 16, 2013 @01:07PM (#43464253) Journal
    This is just talking about exponential growth rates and using that to estimate the start of life. Apparently, the editors of /. can't understand exponential growth without thinking of Moore's law.
  • Look, we already know that genetic diversity doesn't increase at any predictable rare. For most pf life's existence on earth it was limited to anaerobic bacteria and that there was very little genetic diversity. Then the oxygen levels in the oceans and atmosphere reached saturation levels and aerobic live took over. And with the higher complexity of possible life forms, the increase in reproductive frequency, and the over-all speedup of this rocket-fueled form of life genetic diversity exploded.

    • Not true. Histones, the proteins that keep DNA ordered, are some of the earliest proteins. They provide an extremely accurate clock for when species diverged.

      While on a short term, a few million years, you are right when you say the rate of genetic drift is not predictable. However, over a longer period of time the rate SEEMS to be fairly consistent. That is the point of the article.

      You seem to be confusing genetic diversity with Phylogenetic diversity. Phylogenetic diversity describes how genes change

  • by Anonymous Coward on Tuesday April 16, 2013 @01:17PM (#43464361)

    "SARS and the Origin of Life"
    "Horny Rabbits and the Origin of Life"
    "Rice on a chess board and the Origin of Life"

    PROTIP: Just because there is exponential growth doesn't mean a subject has anything to do with Moore's "Law".

  • by mark-t ( 151149 ) <markt AT nerdflat DOT com> on Tuesday April 16, 2013 @01:27PM (#43464463) Journal

    "life as we know it originated 9.7 billion years ago."

    Uhmmm.... "life as we know it" happens to be limited to life that originated on Earth. Earth isn't 9.7 billion years old. I trust you can see the problem with this notion.

    Certainly the possibility exists that life on earth actually originated elsewhere and happened to land here after the earth was formed, this is far from an actual testable scientific theory until at least we find any evidence of life outside of this planet that we can verifiable say did not come from here.

    • mark-t wrote: ""life as we know it" happens to be limited to life that originated on Earth."

      They are not saying that, they are saying the opposite of that. That "life as we know it" here on Earth does not happen to be limited to life that originated on Earth, and that life not originated on Earth is, in fact, the life that we know.

      It may very well be completely wrong, but the premise per the summary is not inherently illogical.

      • by mark-t ( 151149 )
        They might be saying exactly the opposite, but saying doesn't make it so.

        Regardless of how probable life elsewhere might be, our limited knowledge of the universe right now is such that the life which is right here on Earth is genuinely the only life that we know exists in the entire universe. Sure there can be life elsewhere, but we don't actually know about it yet.

  • Extrapolation! (Score:5, Insightful)

    by nedlohs ( 1335013 ) on Tuesday April 16, 2013 @01:40PM (#43464597)

    what could possibly go wrong, particularly when you extrapolate twice as far as you actually have data for.

    • The extrapolation on the other axis is even more fun. "Let's extrapolate six orders of magnitude down from the simplest known life (twice the log range of the entire span of known life), assuming the mechanics of complexity works exactly the same in the region between 10^6 and 1 base pairs!"

  • What I'm interested in is how MIT came to be in possession of a Cornell paper. Were they strictly authorized to use the paper in such a manner? Did they actually use their proper login credientials? Did they tell Cornell in advance of the fact they wished to cross state lines with it? If the answer to any of the above is "no" can we hound them to death about it like they did to Swartz?

  • by cervesaebraciator ( 2352888 ) on Tuesday April 16, 2013 @01:54PM (#43464743)
    This is clearly a solid comparison since I found a related correlation between Moore's law and humanity. Having met humanity, I can definitively say that the software doesn't take full advantage of the hardware's advances.
  • This nicely explains where missing mass of the universe went - Dyson Spheres. I always thought "dark matter" suffered from Occam's Razor.

    • by dargaud ( 518470 )
      Missing mass ? I didn't even know matter was catholic, so how could it miss mass ?
    • Aside from the evidence (via gravitational lensing measurements) for dark-matter halos with distinctly different spatial distributions from known-matter galactic disks (loose "blobs" indicating different, extremely-weakly-interacting types of matter than the normal stuff that accretes into galactic disks). So, your "Occam's Razor" solution is that observed mass distributions (consistent with two types of matter, visible/interacting and "dark"/non-interacting except through gravity) are due to super-advanced

  • by femtobyte ( 710429 ) on Tuesday April 16, 2013 @02:12PM (#43464913)

    The critical "plot" in the article from which the age estimate is derived has 6 data points: "prokaryotes," "eukaryotes," "worms," "fish," and "mammals." Nowhere in the article is the selection criteria for these 6 particular categories explained. In other words, out of the hundreds of major categories of life which the authors might have chosen to plot, they arbitrarily pick 6 that vaguely fall on a log-linear line (with a bit of fudging for "functional, non-redundant genome"). Give me a big scattery cloud of hundreds of potential data points, and I can reach whatever conclusion you want with the proper selection of a half dozen.

  • by Anonymous Coward on Tuesday April 16, 2013 @02:38PM (#43465213)

    The article really is not convincing, for several reasons:
    Their graph, the one that supports the whole enchilada, has five data points. Color me unimpressed that they were able to fit a function to five data points. Furthermore, the specificity of classification even within the graph varies a lot- prokaryotes are a much broader classification than worms, fish, or mammals. Is there variance in the amount of functional base pairs within the prokaryotes? I don't know- I'm not a biologist. Their paper doesn't clarify this point at all. How do I know that they are not cherry-picking their organisms to fit an exponential curve?

    They're extrapolating backwards without good justification. Even if the growth is exponential, what affects the time constant? Some organisms reproduce slower than others, which surely affects the exponential rate of growth. If bacteria existed on space-bound pieces of rock, would they be able to reproduce at the same rate as a bacterium in a pond? Surely the microbiology of the "first organism" would be very different than that of organisms many billions of years following? Would mutations occur more rapidly in space, increasing the rate at which function base pairs would grow?

    They assume the origin of life had one base pair. I'm not a microbiologist- does it make sense for the DNA of the first organism to have one base pair? If the organism instead had 10 base pairs, their estimate for the origin of life is knocked forward by a billion years or so. Even without that, the error bars on their analysis are +/- 2.5 billion years, just due to statistical uncertainty.

    They reference a "Another complexity measure yielded an estimate for the origin of life date about 5 to 6 billion years ago." Why are the results so different? What were the error bars on their data? They claim that those results are incompatible with an origin on Earth, but if the error bars are similar to those on their claims, then that statement doesn't hold water.

  • Article says predecessors may have evolved around the predecessor star to our Sun, but given the time spans involved why just our sun? If early bacteria were ejected into space by vulcanism, solar wind would accelerate them outwards to ~400km/s, or about .1% speed of light. At that speed, you could cross the galaxy in a scant 100 million years.

    Depends on what happens to low-weight particles at the heliopause though, especially if they've become ionized during travel.

  • by tbird81 ( 946205 ) on Wednesday April 17, 2013 @01:21AM (#43469803)

    4000 transistors per IC in 1975, 2000 in 1973...

    The integrated circuit was invented in 1951.

    I'm sure this is scientifically sound.

"The vast majority of successful major crimes against property are perpetrated by individuals abusing positions of trust." -- Lawrence Dalzell

Working...