Can We Solve the Mystery of the Origin of Life by Creating Life in the Lab?
Denyse O'Leary March 24, 2014 4:19 AM
Francis Crick said in 1981, "Every time I write a paper on the origins of life I swear I will never write another one, because there is too much speculation running after too few facts, though I must confess that in spite of this, the subject is so fascinating that I never seem to stick to my resolve."1 He isn't alone. With unmistakable dejection, Christian de Duve listed a number of OOL theories -- pyrophosphate world, iron-sulfur world, thioester world -- adding, "opinions are divided on what has been accomplished by all this activity. While much has been learned, it is clear that we are still nowhere near explaining the origin of life."2 James Shapiro said bluntly in 2010 that origin of life theories are "still on the fringes of serious scientific discussion."
One group is charting a genuinely new path. Nobelist Jack Szostak seeks to construct an origin-of-life grade cell: "You want something that can grow and divide and, most importantly, exhibit Darwinian evolution. The way that we study that is by trying to make it happen in the lab." He thinks he has succeeded with the cell membrane but "genetic material is the harder problem; the chemistry is just more complicated." And well-known origin-of-life researcher Gerald Joyce thinks that "alien" (i.e., alternative) life forms will more likely be constructed in a laboratory than found in space. Richard Dawkins is optimistic about such efforts: "I watch from the sidelines with engaged curiosity, and I shall not be surprised if within the next few years, chemists report that they have successfully midwifed a new origin of life in the laboratory."
The lab may be the best bet. Science writer John Horgan assesses the current programs unsparingly (but doubtless correctly): "This is by far the weakest strut of the chassis of modern biology. The origin of life is a science writer's dream. It abounds with exotic scientists and exotic theories, which are never entirely abandoned or accepted, but merely go in and out of fashion." We are forever on the verge of a great discovery -- perhaps our hundredth such verge -- but there are no dates proposed for progress evaluation. We can, however, draw some conclusions at this point:
Life's origin on Earth may simply be impossible to determine. It was, after all, an event in time, in history, like the moment the last dinosaur died or the first human fashioned a wheel. If the origin is chance, as most models imply, it is all the more likely to be lost to follow-up.
Life produced in the lab would be a stunning feat but would not necessarily explain life's historical origin. As evolutionary biologist Jerry Coyne told New Scientist, "Even if we can create a 'second genesis' in the laboratory, that won't tell us exactly how it happened on Earth 3.8 billion years ago," adding "There are so many different scenarios for how life got going and they all involve molecules that don't get fossilized. It's a clear limit." Astrobiologists argue that life could get started a number of ways elsewhere. A successful lab experiment does not rule out other scenarios, on Earth or anywhere else.
Researchers who design their experiment so that life "just happens" a certain way in the lab are not ruling out design. A gaming commission designs a lottery to assign winning tickets randomly, using a computer algorithm. But the algorithm was designed to assign the numbers randomly. For example, a math genius might then game the algorithm by detecting the design and arranging his ticket purchases to greatly improve his odds. But, if so, he is substituting design for design, not design for chance. Indeed, one Toronto, Canada, statistician did something like that, demonstrating to the gaming commission a flaw in the algorithm for assigning the numbers, such that a design could be detected (and the game was changed as a result).
In short, setting ethical concerns aside for the moment, creating life from scratch in the lab is the only strategy that could, in principle, yield results that are subject to normal science investigation (controlled conditions in the present day). But it would not demonstrate either that life came into existence by that method or that it came into existence without design. Quite the opposite; we would now have a method of creating life by design -- but still no known methods that do not include design.
Could we at least apply what we learn from designing life ourselves to the lost events of deep time? Maybe. But the most reliable methods for producing life in the lab might require the most intervention or feature the conditions we think least likely on early Earth. On the other hand, we could at least test panspermia models. Best results stemming from Mars or asteroid simulations would support panspermia far more strongly than lack of success with Earth-based models (really, panspermia is then just an argument from desperation).
And -- some may think this benefit alone worth all the trouble, risk, and expense -- we could ignore dozens of sketchy model-of-the-month scenarios based on contested claims about Earth's history. Either a model creates life or it isn't ready for prime time. Science journals can then dispense with complex conditional tenses like "might have had," "could have had," and "would have had" when writing about the creation of life.
In short, the lab approach offers an all-science-and-no-religion way out of the present quagmire, with the likelihood of at least some useful answers. Why not just generally adopt it, or at least work toward it? One problem is that it doesn't support claims about the vast powers of randomness or the brute laws of nature. And no solution that dismisses both can be regarded as "science" today. So origin-of-life projects continue to head off in dozens of directions to nowhere instead.
But they at least remain free of any taint of design.
References:
(1) Francis Crick, Life Itself (1981), p. 153.
(2) Christian de Duve, "Mysteries of Life", in Bruce L. Gordon and William A. Dembski, The Nature of Nature: Examining the Role of Naturalism in Science (Wilmington, DE: ISI Books,
2011), p. 349.
2011), p. 349.
No comments:
Post a Comment