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Study Puts Hole In Comet Theory Of Life's Origin
Astervitude writes "A new study by US and Japanese scientists has put a serious dent into one version of the popular panspermia theory that credits comets for bringing the seeds of life to Earth. Surveys conducted by the University of Arizona, the National Astronomical Observatory of Japan and others now show that objects from the main asteroid belt between Jupiter and Mars were largely responsible for the period of Late Heavy Bombardment that ended 3.9 billion years ago. UA Professor Emeritus Robert Strom believes that no more than 10 percent of the Earth's water comes from comets and any oceans then extant would have been 'vaporized by the asteroid impacts during the cataclysm.'" Interesting, because this directly contradicts the Nova mini-series Origins that just finished running on PBS. Science never stops moving.
Increasingly complex molecules competed for energy and material to form larger and more sustainable molecules. The molecules that arranged themselves by chance to absorb the most energy and strongest structure surivied the longest, and this process continued until basic structures combined in a symbiotic relationship that would help sustain the period of those structures existance. This process continues until basic cell structures formed, and again combined by chance to form larger structures. Eventually the strongest and most energy effecient structure was developed by chance through the process of natural selection until we had basic repoductive structures. Mutations which led to longer life and thus more chance of reproduction continued until movement and adaption were constituents, from there entire structures began to work together to from basic cells, which over time developed processes for reproduction and survival through chance combination and mutation. Cells began to grow in complexity in a bid for survival, by chance some began working together to form multicellular groups, which became organisms with adaption relative to the abilities of each cell, then came encoded cellular variation to ensure multicellular groups continued to form by precedence. Over much time increased numbers of simple structures combined to form larger and more complex structures witht he ability for their own kenetic movement beyond growth, because of the natural selection of moveable multicellular organisms made them more adaptable then others and thus more likely to reproduce. Eventually all sorts of mutation and chance combination occured which would lead to ever more complex structures with better adaptability till the first regonizable biological systems formed. From there we have basic sea life and countless steps later down the evolution chain, human beings.
Of course, it might be out of order, and one would have to know that the time this would take would be immense.
For those who make the chance argument, stateing that such complex structures canot possibly arise by chance i say:
Look at the size of the universe, there must be at least 125 billion galaxies, each with roughly 100 billion stars, each with the possibility of terrestrial planetoids, each with a massive surface area with plenty or energy and materials for the possibility of forming the molecular strutuces by chance that are a prelude to life. Then take that number, and times it by the age of most galaxies.....All of a sudden the chance doesnt seem so small.
As for complexities, whos to say life is complex, its equally possible that life is mearly countless basic systems working symbiotically for the goal of survival and reproduction. I give the cargo cult as ana example: In World War 2 several tribes worshiped American cargo planes because the ability and complexities of human flight were so vast to them that the cargo planes could only be explained as items of a supernatural nature. It never appeared to them that these planes were not godly and no complex beyond their understanding, such is a cargo plane simply a number of systems discovered by humans by chance working in parrallel.
As for thurther complexity: If life is so complex that the possibility of chance is so small, then how does one explain oru manipulation of life, for example insulin producing bacteria, or the mapping of the genome. How does one explain the evolution and appearance of new viruses and bacterial strains by chance.
Life is beautiful, it is wonderous and magestic, but it is not beyond our understanding. It arose by chance, it's growth is determined by evolution and it is not complex. It just appears that way to some.
I always think, that maybe the reason ID and creationalists fight progress and science is they think that discovery is taking the magic and beauty away from life. But instead, what they dont realise, is that all it is doing it discovering more beautiful and wonderous details. We are not finding answers, only more questions. We are giving power to ourselves and whatever purpose we serve. There is no need to be afraid, no need to be ignorant, only a need to be open to the wonders that surround us and fuel the need for discovery that comes with conscienceness.
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Although the panspermia theory is intriguing, it does NOT answer the question of the origin of life -- was it from another planet that was inoculated by an even earlier comet..... It's like the theory that the Earth rides on the back of a giant turtle/ But what does that turtle ride on? Or is it turtles all the way down.
If we are to assess the probability that life is exogenous or endogenous to Earth, we must ask about the relative probability of: a) life forming on a planetary body versus b) life forming on a planetary body which then survives being blasted into space, travelling interstellar distances, happening to collide with another forming planet of just the right composition (without ever venturing too close to some hot star), and surviving that collision.
Even if the probability of life arising on a planet very very low, the relative probability of endogenous versus exogenous origin is very skewed toward endogenous origin. Because exogenous origin requires both endogenous origin (somewhere else) and then a low probability trip between planets, exogenous origin would seem to be very unlikely unless there are large numbers of planets with endogenous life that spew lots of interstellar-traversing chunks. But if there are large numbers of planets with with their own endogenous life, then the probability of life forming on Earth endogenously must also be high and trump the low likelihood of life just happening to make it from somewhere else.
Two wrongs don't make a right, but three lefts do.
Well, I will point out that the various theories of Creation in the last few hundred years has been far more stable than any scientific theory put forward.
That is because ignorance is stable.
Perhaps it would be better if science types started using rhetoric like "We Think" or "We Believe" instead of "We now know..."
We 'science types' usually do. The problem is that if we start saying 'we believe' too much in public, our ideas get attacked as 'just another form of religion'.
I mean, the version of Darwinism that was taught in my school has pretty much been shot to heck, but my Biology teacher sure enough said, "This is how it happened."
That is because the science taught at school has to be simplified hugely. The version of almost any scientific idea taught at school is largely wrong. The idea is to open minds to the principles of science.