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Scientists Offer 'Overwhelming' Evidence Terran Life Began in Space
An anonymous reader writes "Using data from recent comet-probing space missions, British scientists are reporting today that the odds of life starting on Earth rather than inside a comet are one trillion trillion (10 to the power of 24) to one against. That is, we're not originally from around here. Radiation in comets could keep water in liquid form for millions of years, they say, which along with the clay and organic molecules found on-board would provide an ideal incubator. 'Professor Wickramasinghe said: "The findings of the comet missions, which surprised many, strengthen the argument for panspermia. We now have a mechanism for how it could have happened. All the necessary elements - clay, organic molecules and water - are there. The longer time scale and the greater mass of comets make it overwhelmingly more likely that life began in space than on earth."'" jamie points out that the author of this paper has many 'fringe' theories. Your mileage may vary.
That's where God lives.
The great anthropologist Dr. Douglas Adams already showed that we did not originate here. In fact, we were passengers on the 'B' Ark that crash-landed here. Our ancestors come from an ancient civilization called Golgafrinchans. It is a shame that Dr. Adams's work is so widely ridiculed as a "humorous" bit of "fiction" in wider scientific circles.
I for one welcome... uh, myself.
Dewey, you fool! Your decimal system has played right into my hands!
In a manner of speaking, didn't everything start in space?
In an ironic statement, they also claim Protoss life began on Earth...
There was never a better time to tag a story nevertellmetheodds!
Is it just my observation, or are there way too many stupid people in the world?
Soooooo, they used two numbers (mass of clay & # of comets) to generate a 1e24 to 1 odd against life having started here? Seems like they might have left one or two variables out of their equation. Hopefully this is just junk reporting rather than junk science.
1984 was supposed to be a warning, not an instruction manual.
So the odds of a combination of clay + radiation was only to be found inside comets and the chances of that surviving a fiery impact at many kilometers per second are _higher_ than the same combination occurring naturally, peacefully, here on earth ? Somehow my bullshit meter goes all bananas.
Religion is what happens when nature strikes and groupthink goes wrong.
Please before you mod me troll, listen. The Theory of evolution does not explain the origin of life, just the origin of species. Most folk who believe in things like ID (I= intelligent or idiotic depending on your perspective) confuse the issue and attack science. Let us not make the same mistake on the science side. Even the most ardent supporters of the Theory of evolution, like Dawkins, have only proposed very tentative speculation about the origin of life. They readily admit that right now science does not have any definitive theories about the Origin of Life.
This has nothing to do with evolution. Let us keep the discussions straight.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
Is there any evidence that comets have such isotopes at such concentrations? This sounds like the sort of thing Lex Luthor would be involved in.
What I'm listening to now on Pandora...
It's much worse than that. Like all panspermia advocates, and like a good many Creationists, they essentially crib the "odds" argument. This looks no different than any other pro-panspermia "study" in that it starts with a strawman of abiogenesis.
The world's burning. Moped Jesus spotted on I50. Details at 11.
When I was in grad school our group was trying to make a particular type of superconducting circuit. After many attempts we got one that worked, wrote it up, and presented it at a conference.
During the Q&A, someone asked my advisor what our yields were. "On a good day, 100%". The followup question was, "what's your yield on good days?"
It's not wasting time, I'm educating myself.
It's junk science. Wickramasinghe and Hoyle are the same two who concocted the absurd probabilistic "tornado in a junkyard" argument against evolution. Hell, during the SARS outbreak, Wickramasinghe suggested that SARS was an alien virus. Yep, it just happened to have a sequence remarkably similar to other earth-borne viruses, and just happened to fall to earth in a region where similar viruses infected wild animals. Yep, that's the ticket.
Hoyle at least used to be a real scientist. I'm not sure if Wickramasinghe ever was. He said "
"The chances that life just occurred are about as unlikely as a typhoon blowing through a junkyard and constructing a Boeing 747" in 1982, so he's been a crackpot for a long time. This guy's just one step less crazy than Behe and the other 'intelligent design' crackpots. The only difference is that the intelligent designer posited by Wickramasinghe and Hoyle is a natural one, not a supernatural one; all the other problems with their claims are the same.
want to tell us that life was created by random comet falls?
i demand equal time for the godly and righteous theory of intelligent comet placing!
comets did not just fall randomly to earth and create life!
god himself intelligently directed comets to come to the early lifeless earth 6,000 years ago!
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
British scientists are reporting today that the odds of life starting on Earth rather than inside a comet are one trillion trillion (10 to the power of 24) to one against.
That they can even presume to put a number on the probability of life is evidence enough that they have no idea what they're talking about.
Anyway, the odds of life are totally irrelevent to anything. See: anthropic principle.
Sometimes it's best to just let stupid people be stupid.
Also in the news this week is the opposite result: that life cannot exist in comets because of the radiation. So... it's not obvious (to me) that there is any scientific consensus on this topic.
Panspermia: When God masturbates.
What is an "old" comet? No comet we're going to encounter is going to be any older than the solar system itself. Most of these comets would, in fact, only be a few hundreds of millions of years older than the Earth itself, and quite likely would have spent a great deal of their time on the outer bounds of the solar system.
We know that life was here between 3.5 and 3.9 billion years ago, with some iffy evidence suggesting it was even older. That gives us a net time advantage for any given comet of no more than about 500 million years. That sounds like a lot, but in reality it really isn't that big a span. Beyond that, considering that our knowledge of cometary history is still rather sketchy, and that our sample size is exceedingly small, this is nothing more than a pretty substantial "what-if", itself based upon one particular abiogenesis theory, which has been somewhat supplanted in recent years.
If we're going to start talking about interstellar comets, to add more time to the equation, someone is going to have to a) provide evidence of such bodies and b) provide evidence that radioactive decay is going to produce heat long enough for liquid water within the body to act as an incubator for the VERRRY long stretches of time that some organisms or proto-organisms are going to survive.
Now, weight all of this against the fact that the early Earth had all the ingredients for life to develop; *plentiful* amounts of liquid water and lots and lots of energy (in the forms of solar radiation, atmospheric conditions like lightning and geothermal energy from oceanic vents and vulcanism). Can someone kindly explain to me how a comet, even with clays or clay-like crystaline minerals and some sort of low-level radioactive decay (it has to be pretty low-level too, because anything too energetic or in too high a quantity is more likely going to be delerious than helpful) is going to provide this more wonderful environment.
As with every generation of panspermia advocates, the underlying argument is essentially "We don't think there was enough time for life to develop on the early earth, so we've got to find a way to add more time." Even if we give them this part of the argument (and I frankly think even that is FAR too generous), they still have to explain how conditions elsewhere (comets, other planets orbiting other stars) are somehow more environmentally-friendly to abiogenesis than Earth was.
This is not to slight the largely unrelated idea that comets could have been the source of organic molecules that could have been some sort of organic "seeds" for early self-replicators to develop and to use as raw materials and energy.
The world's burning. Moped Jesus spotted on I50. Details at 11.
we-are-all-made-of-stardust dept... close, but Sagan's line ended with 'star stuff', which is actually more appropriate here.
As to the relative plausibility of comet-seeded or locally-formed progenitors to life, given that reactions propagate, commonly leading to repeating and self-feeding cycles of reactions, the only argument for extra-solar is the added timescale and potential additional area for productive area for pre-life to evolve in.
Given that the universe is 13.7 billion years old, and the earth is 4.5 billion years old, and life on the earth is nearly that old, and that the universe has only been cool enough to support planets or life for much of that time, I don't believe panspermia buys us that many more orders of magnitude of time to work with.
So, it doesn't buy us time, how about area? Again, I can only guess using very rough psuedo-numbers here, but the matter we could get from previously existing worlds or small super-fertile comets has to come from somewhere previous. Given the expanding nature of the universe, we're generally only going to be getting a pie-slice of potential sources for any life-by-projectile, and each of these sources has to have been fed by enough nuclear sources to make the building blocks of simple pre-life. I can imagine a multiplication of potential sources this way, and even though it would only take one source to seed the whole set... just imagining the mass that actually makes it into out solar system, and then actually hits our earth... that likelihood doesn't seem much stronger than the numbers we think of with abiogenesis via selective pressures here on earth.
Ryan Fenton
I had Prof. Wickramasinghe was one of my Pure Maths lecturers during my first year at Cardiff. He was dreadfully hard to understand.
t icity
My flatmate, who was a paleobotany postgrad at the time, had some very disparaging things to say about him. He had co-authored a few papers claiming the Archaeopteryx was a hoax, based on his poor understanding of the subject matter.
http://en.wikipedia.org/wiki/Archaeopteryx#Authen
I can't believe that they really can begin to propose odds like that on life's origin. What if life didn't begin with clays acting as catalysts for chemical reactions but instead required a reducing atmosphere? (Current thinking is that life originally used hydrogen sulfide as an energy source, possibly from undersea "smokers"). Can the comets provide that kind of environment? What would happen when the few nascent life forms that survive the planetary bombardment that they are part of are dumped from their interplanetary cocoons into the tremendously different environment of the early earth? Don't you think that there is a good idea that the life forms that survived that environment were the ones that evolved there?
Add to that the fact that we really don't have a clue as to how life started here (or anywhere else for that matter) and you really begin to question the judgment of giving odds to this sort of thing.
I'm not saying they're wrong, I like panspermia theories as well. It's just for people to put some sort of numerical values on this kind of thing when we know so little is just well crazy. And what numerical values! Maybe after if we send out some cometary probes and find them teeming with primitive life could you claim such a thing. Even then do they use DNA or RNA? Any evidence of spectral emission lines of this from any of our flyby probes? (It would be even more earth-shaking if there was DIFFERENT life there!)
Still I enjoy reading ScienceDaily.com. (Daily in fact) It's a great site not like some pseudo New-Scien(tist) kind of site.
For those interested in why the tornado in a junkyard assembling a 747 is a useless analogy for the process of evolution, the simple explanation is that evolution works by a ratcheting effect: improvements are made one tiny step at a time, in sequence, for a cumulative effect of complexity. The selection process by which those steps are made - i.e. mutations that constitute an improvement in fitness survive and others die out - is simple and nonrandom. The tornado analogy implies instant emergence of full complexity, which is nothing at all like what actually happens.
A-Bomb
It's a main argument that might have made more sense half a century ago when our best data was limited and our experimental evidence was largely Urey-Miller. The growing body of evidence, while still woefully small, suggests that the kinds of chemical reactions that might be needed to go from prebiotic organic matter to some sort of proto-life may not require all that much time at all. What seems to take a lot of time is moving from more primitive prokaryotic organisms to eukaryotes, and on to the more complex plant, animal and fungal forms that we see today.
I think the most basic problem with panspermia is that it seeks to solve a problem that we don't even know exists yet. It seems to violate Occam's Razor by adding a good many entities to the abiogenesis argument, and still doesn't really answer the origins issue, merely pushing it back.
If, and I'll admit at this moment that it is an if (big or little), life requires water (or some liquid capable of dissolving and suspending molecules for more complex organic chemical processes to occur), along with energy, it would seem that the early Earth had both of these in abundance. There are problems with modern abiogenesis theories, there is no doubt about it, but the problem with panspermia models is that they do no better job of answering the real dilemnas than other abiogenesis theories, save perhaps that it adds more time, though in an environment that is extremely hostile to life, particularly over long periods of time.
Panspermia seems to commit essentially the same error as Intelligent Design, by insisting, with really no evidence at all, that there is something so inherently complex in life that the time between the formation of our planet and the cooling stabilization of the surface was insufficient to produce life. The problem here is largely in what these arguments tend to think of as life and what abiogenesis researchers are referring to. There seems to be this attitude that life must have, under terrestial abiogenesis theories, sprung up pretty close to being recognizably modern, when in fact, it seems far more likely that there was a progression from some sort of primitive self-replicating molecule through a number of evolutionary stages until we end up with the first primitive cells (which might not, other than being bags to isolate internal chemistry for the external environment) necessarily resemble modern life at all.
We do know that there was plentiful amounts of energy on the Earth at that time, and if energy is ultimately the major engine driving the evolution of life from organic molecules into forms we could confidently call living organisms, then time may not be that much of an issue at all. We're still talking about about a hundred million years or more here, and if life couldn't form in a hundred million years, how does increasing that by a factor of five make it that much more likely.
I won't even get into the really goofy trans-stellar or trans-galactic versions of panspermia, which are even harder to defend.
The world's burning. Moped Jesus spotted on I50. Details at 11.
"Either is happens, or it doesn't"
And there was a 50/50 chance that I'd get the punchline right, and I got it wrong thanks to a spelling mistake.
Either it happens, or it doesn't.
Saskboy's blog is good. 9 out of 10 dentists agree.
Spore delayed to add pre-cell comet level
I never got why panspermia was such a compelling theory. It just pushes the real question, "how did life begin", back a little. Maybe life on earth started from genetic material on a comet. That genetic material had to come from somewhere, so that just means that abiogenesis occurred on a planet other than earth. Why is abiogenesis elsewhere more likely than abiogenesis here?
Give me Classic Slashdot or give me death!
It's the 'separation from god' that really scares the suckers. I'm sure if 'hell' were a bottomless pit of fluffy pillows, there would be just as many believers.
Blar.
The thing to keep in mind here is what Creationists do when they come up with this "bazillion to one against x happening" claim is that they're usually trying to argue for the occurence of an entire novel feature out of some base system (ie. bacteria from an organic soup). Well of course, that's so unlikely as to be impossible (though I still think one should demand to see the work behind even this kind of claim). But that is nothing more than pushing over a strawman of what abiogenesis theories state. No modern theory claims that anything like a modern cell popped out of the first abiogenesis event. Quite the opposite, the basic notion is that the first products of such an event probably wouldn't even be considered life. They were replicating organic molecules. Abiogenesis wasn't one giant leap, but a series of intermediate steps that ended with something approaching what we would view as a cell.
In short, these great big statistical arguments against abiogenesis aren't even arguments against any hypothesis that scientists are putting forth.
The world's burning. Moped Jesus spotted on I50. Details at 11.
We can start with the fact that macro-evolution (as defined by biologists, and not creationists) has been observed (that is to say, evolution beyond the species level).
There is a fairly (and far beyond me to explain) statistical aspect to evolutionary biology, but the main thing to keep in mind is that modern evolutionary theory predicts that all life, extant or extinct, will fit into a nested hieararchy. The bonus of the Modern Synthesis and of the last thirty or forty years of genetic research has given us a twin-nested hiearchy; not only do the fossils give us a pretty good notion of the faunal succession, but the genetic data, by and large, confirms and extends those observations.
This is the root of why evolution is a well-supported scientific theory. It's nice to have a single line of data, but when you get to evidentiary lines that fit together as well as the fossil and genetic data does, I don't think it's any great leap of any kind to state "Here is evidence for common descent".
Let's remember the flip side of all of this, and that's falsification. For common descent to be falsified, one need only provide some examples of organisms that fall outside of the twin-nested hieararchy, or of fossils that violate the faunal succession. So, if you can produce some bacteria that uses an entirely different genetic scheme that is not related in any way to the way life as we know it does, then common descent has been falsified (though, you'll note, evolution has not). As to the faunal succession, if you pull a rabbit fossil out of strata, say, 3 billion years ago, where bacterial colonies represented the most complex organisms around, then we have a very serious problem.
Now, how do we falsify a common Creationist retort; that God (or the Designer(s) or whatever) used a common toolkit, and that's why all life uses the same basic nucleotide system, or genetic language if you will. On the face of it, it seems a reasonable retort, until your factor in that said Designer likely could use any genetic he/she/it/they pleased, and there's every reason to expect that there might be a half a dozen, or a hundred or any number you like (and can expect to be likely to be useful for inheritance) such systems as there is just one. In short, any and all observations are essentially compatible with the claim "God did it" (or whatever formulation of God/designer/alien scientist/etc. you want to invoke).
The reason Creationists are picked on for their "million to one, 747 out of a scrapyard" arguments is because those arguments do not in fact address anything that modern evolutionary theory or Common Descent states, but rather knock down oversimplified and rather silly strawmen of what those theories claim happened. There's nothing positive in their claims, simply just fallaciously-formulated arguments against everything from the Big Bang to the formation of the first cell.
If one observers that all extant organisms fit into a hieararchy, then I don't think it's an inference too far to state that that relationship is more than just happenstance. If that observation fits within the predictive nature of a specific theory, then is it unreasonable to state that that observation is in fact a piece of evidence for that theory?
The world's burning. Moped Jesus spotted on I50. Details at 11.
The conditions of early Earth can be determined to some degree, and the time between Earth forming and the earliest known signs of life can also be determined. Any theory which states that life began on Earth has to explain how said conditions lead to life in said timeframe. This far none has.
Panspermia, on the other hand, claims that life was born somewhere else at some point after the Big Bang and earliest signs of life on Earth. "Somewhere else" doesn't constrain the possible set of circumstances nearly as much as "on Earth", and the timeframe is far longer too. It is also impossible to prove false.
Given the choice between lots of time-consuming chemistry reasearch and a hypothesis which is impossible to falsify or really even research but allows a lot of poetic pseudo-philosophical nonsense in the vein of "we are children of the stars", "cosmic bortherhood", and "the thrut is out there", which do you think people will choose ?
Forget magic. Any technology distinguishable from divine power is insufficiently advanced.
Space is very big, and planets are very small. Given enough time (billions of years), any rogue comet may eventually be influenced by a planet's gravity. But that doesn't mean it will hit it. Gravity doesn't work like a frog catching a fly; chances are the gravitational influence will merely change its course. And chances are that influence will be small, unless it passes close to a large planet. The comet would have to be heading pretty much straight at a planet in order to hit it. Even if it were to skim the outer atmosphere, it's unlikely that it would enter a terminal orbit.
Consider this: The Earth is 8000 miles in diameter. The distance from the Earth to the moon is 239,000 miles. The distance to the Sun is 93,000,000 miles. To put this into perspective, imagine a walnut on your desk. That's the Earth. The Moon is a blueberry on the other side of your desk. The Sun is a car three blocks away. Jupiter is a pumpkin a mile from the Sun Car. Mix in the other planets at their proportional distances, and you still have a lot of space in which a comet (anything from a grain of sand to a pea at this scale) can miss everything as it passes through the solar system.
The only object that will definitely have a strong influence is the Sun, and even it may or may not pull the comet into orbit.
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That would be why the moon is perfectly smooth and fully dent free then yes?