Having gotten a lot of intelligent and thoughtful mail following a recent column on Darwin, a bit of it telling me to read Richard Dawkins, the Amway Salesman of Evolutionism (I have read him, actually), I determined to respond here rather than individually. I promise to shut up on the subject for a long time hereafter.
The Argument from Time Even a Federal Bureaucrat Can Get A Job Done, Given Forever
A staple of evolutionary evasion is time, lots of it. This is particularly applied to the putative formation of the OC (Original Critter). One intones “billions and billions and billions of years,” the implication being that with so very, very, very much time, so many billions of gallons of sea water, surely an OC would have to form. Why, it could hardly help it.
Not necessarily. Probabilities can be more daunting than one might expect. Things that seem intuitively likely sometimes just flat are not. To illustrate the point:
We’ve all heard Sir James Jeans’ assertion that a monkey, pecking randomly on a typewriter, would eventually produce all the books in the British Museum. This may sound reasonable, even obvious, at first glance. But would the monkey in fact ever get even one book?
No. Not in any practical sense.
Consider a thickish book of, say, 200,000 words. By the newspaper estimate that there are on average five letters per word, that’s a million letters. What is the likelihood that our monkey, typing continuously (we ignore upper case and punctuation), will get the book in a given string of a million letters?
He has a 1/26 chance of getting the first letter, times a 1/26 chance of the second, and so on. The chance of getting the book in a million characters is therefore one in 26 to the millionth power. I don’t have a calculator handy, but we can get an approximation. Since 26 = 10(log 26), then 261,000,000 = 10(log 26 x 1,000,000). Since log 10 = 1 and log 100 = 2, log 26 has to be between, somewhere on the low end. Call it 1.2.
The monkey thus has one chance in 1 followed by 1,200,000 zeros. That is what mathematicians call a GBH (Great Big Honker). For practical purposes, one divided by that rascal is zero. If you had a billion billion monkeys (more monkeys than I want) typing a billion billion letters a second, for a billion billion times the estimated age of the universe (1018 seconds is sometimes given), the chance of getting the book would still be essentially zero.
Well, you might say, that is asking a lot of our monkey. How about the chance that the monkey would get the mere title of a book—say, On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life, the original title of Darwin´s book. If my finger count was correct, that´s 117 letters and spaces. Then the probability is 1 in 26117, or 10(log 26 x 117), giving 10140 and change. Now, again taking the age of the universe as 1018seconds, our monkey would have, sigh, essentially zero chance of getting even the title. Ain´t gonna happen.
Does the chance formation of an Original Critter involve such forbidding numbers? I don´t know that it does. Nor that it doesn´t. It is difficult to calculate the probability of an unknown process of unknown complexity under unknown conditions.
If it Looks Like a Duck, It Must Have Descended from a Duck
Another argument holds that the similarity of organisms establishes evolution from common ancestors. But similarity can equally result from modifications to a common design. Similarity in itself establishes neither.
Consider the automobile. In the Cambrian age of cars, the Model T appeared. It was primitive and poorly adapted, but under the selective pressure of the market cars became faster, more powerful, and more reliable. Some species died out—the Stanley Steamer, the Dusenberg. The survivors proliferated and became differentiated as they moved into different environmental niches: Dump trucks appeared, adapted to mines and construction sites. Ferraris learned to survive on race courses. Police cars developed the tools of predation, such as sirens.
Yet all share pistons, con rods, wheels, and cam shafts. Is this similarity due to biological evolution, or modification by engineers of an underlying design?
When I was fifteen I was an avid reader of New Scientist, which was then written in decent English. (It has since evolved backward.) In that publication I found from time to time articles on how life might have originated chemically. The question was always how, not whether. The suggested circumstances of this origination varied greatly. They never established how life actually did originate, or showed that it could be replicated in the laboratory, or calculated other than vaguely what the chance might have been, if any, of inadvertent origination.
These different theories often required different sorts of primeval ocean, easy enough because no one really knew what the primeval oceans were like. Thus any ocean within easy rifle shot of reason could be assigned to undergird a preferred theory. Callow youth that I was, I began to suspect that the authors didn´t know what they were talking about.
That was a tad over fifty years ago. Today, glancing at “abiogenesis” in the Wikipedia, I find the same thicket of desperate hypotheses, though amplified by decades of imagination. Peruse the following list of hopeful originations and see whether it gives you a warm sensation of certainty.
- Current models
- 3.1 Origin of organic molecules
- 3.1.1 “Soup” theory
- 3.1.2 Eigen’s hypothesis
- 3.1.3 Hoffmann’s contributions
- 3.1.4 Wächtershäuser’s hypothesis
- 3.1.5 Zn-World hypothesis
- 3.1.6 Radioactive beach hypothesis
- 3.1.7 Ultraviolet and temperature-assisted replication model
- 3.1.8 Models to explain homochirality
- 3.1.9 Self-organization and replication
- 3.2 From organic molecules to protocells
- 3.1 Origin of organic molecules
One hypothesis, so help me, is that life began on Mars (where it conspicuously has not been discovered by a platoon of itinerant Mars landers) and drifted to the earth. That is, life began where apparently there has never been life. The flexibility of evolutionary thinking is greatly to be admired.
Note that biochemistry is no longer a new science. Lots of biochemists have passed under the bridge by now. Much research on the matter has taken place. Results: nothing. This is curious since the Original Critter, or replicating gadget, would have to have been relatively simple, no? The more complex, the less likely, with probability probably diminishing exponentially with complexity.
So, one asks grumpily, why has some chemical ubergeek with an overhanging IQ not come up with it? If he did, it would be—God help us—Intelligent Design, but it would at least be proof of principle.
To sleep, perchance to dream….
Obama Got the Peace Prize, Didn´t He?
I subscribe to the DNA-First model. However, it is not the formation of DNA that is hard to explain, but its replication. Given the enormous times involved and a chemically complex sea, it would be surprising if the necessary nuclear bases, adenine, guanine, thymine, and cytosine, did not appear in small amounts. The only other components needed would be a pentose sugar and phosphate groups.
These are not complex and would bind to the nuclear bases to form nucleotides, as they do in the laboratory. But they would have existed in very low concentrations and had short half-lives. The question is how they got into sufficient proximity to form DNA, which is rather more compex.
I propose a new model: PCR, Paleopolymerase Chain Reaction. (No, it does not mean Politically Correct Rumination. But it could.)
Think of tidal pools along the shores of newly-formed continents. These would naturally serve to concentrate substances in the primeval ocean as the sun evaporated the water. Thus the free-floating nucleotides, though at low concentration in the ocean as a whole, would reach more-reactive levels. Given the vast times involved, very likely DNA would end up forming in these pools. Even so, concentrations would be low.
Now, these pools would get very hot in the relentless sun of those times, hot enough to beak hydrogen bonds and produce single-stranded DNA. Then, as high tide brought cooling water to the pools, the free nucleotides would bind to the single-stranded DNA. Thus the original double-stranded molecule would have become precursor to two double-stranded daughter molecules.
The only component lacking for the synthesis would be DNA polymerase. This would almost certainly be present in the oceans, probably having come in on an asteroid. This should not be surprising. It is known that organic molecules have been found in meteorites, notably carbonaceous chondrites. It is further known that the asteroid that produced the Cretaceous-Tertiary extinctions brought iridium which spread over the earth. Polymerase dispersal would seem equally likely.
The paleopolymerase would catalyze the formation of the new DNA. Every tide would carry some of the synthesized DNA into the oceans, and bring in more components to be concentrated by the sun. Cycle after cycle, the level of oceanic DNA would increase. It may well be that actual islands of DNA formed. It is not unreasonable to suspect that the primeval forests of later times grew first on these nutrient-rich islands.
I think the foregoing is brilliant. It has all the requisites of a major evolutionary theory, being irreproducible, implausible, unlikely, and based on improbable assumptions. I await my Nobel.