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Your Environment May Change Your Genes
An anonymous reader writes "Recent experiments indicate that your environment alters your genes. The longer identical twins live apart, the more their "epigenomes" (genetic sequences that activate or suppress other genes) differ. This possibility could cause a radical shift in the assumptions of biological inheritance (namely that, with minor exceptions, an individual's genes do not change), and indicates the possibility of return of Larmarckian inheritance which had formerly been consigned to the dustbin of biology."
You've misrepresenting what the article says: Environment alters gene EXPRESSION, not genes. That makes the whole "Lamarckian" inheritance comment irrelevant, too.
You just need to learn more statistics.
Just imagine.
10 out of 100000 organisms get a light sensor.
They are better, so they become dominant.
Of the mutant offspring, lots do have a tendency to develop more than one light sensor.
More light sensors are better than one.
Now you have a fly-like eye.
Focusing lenses are easy.
The sensor must be protected by something, because it doesn't work otherwise, and the clearer the better, and those who have better focusing clear flesh covers for their eyes, can sense better their environment, and find better partners.
What you view as a huge advantage, can be broken into lots of incremental advantages that are easily explained by evolution.
Of course, it's almost magical that evolution can happen just by birth and death.
You never stop to think that all the tasks a modern computer can perform are just the result of the arrangement of "nand" gates, but there's no magic, and we understand it, because it's simple enough to be understood.
For evolution, it has the advantage of thousands of millions of years of incremental design.
There's another far more powerful effect going on in evolution that people rarely hear about in the common explanations of evolution. The common explanation of evolution is as a sequence of individual beneficial mutations, like climbing a ladder. If that's how it worked then critics would be right, evolution would not have been able to produce the incredible variation and complexity we see today. That kind of advancement is about the least powerful mechanism in evolution.
In fact I'll even assume that every single mutation that occurs is either neutral or harmful and we'll still get the real and powerful mechanism of evolution. I'll give a relatively brief and superficial explanation, but it's a huge topic and this is still going to be fairly long.
A good place to start is with the common complaint of creationists that mutation and evolution "cannot create information". Well in the initial mutation phase they are right. When a mutation occurs it introduces noise, it tends to degrade information. But look what happens the moment that mutation gets passed on to an offspring. That mutation is now no longer random noise, it now carries a small bit on information. It carries a little tag saying "this is a nonfatal mutation". The presence of this mutation in the offspring is new created information, the discovery living record of a new nonfatal mutation. Over time the population builds up a LIBRARY of nonfatal mutations. This library is a vast accumulation of new information.
That information actually undergoes even more processing and synthesis. Over generations beneficial mutations would obviously multiply, but we're assuming there are none of those here. However entirely neutral mutations will also tend to accumulate and multiply. Nearly harmless mutations would also accumulate and multiply to a lesser extent. Somewhat harmful mutations will even accumulate, and extremely harmful-but-nonfatal mutations will pop up and disappear at the rarest frequencies. So not only do we build up a library of nonfatal mutations, the mutations get tagged with a tagged with a frequency, the percentage of the population carrying that mutation. Each mutation is tagged with a measurement. Every mutation now carries a cost/benefit information tag at the population level. The best ones have a high percentage representation and the most harmful ones have a near zero representation percentage. Our library now contains far more valuable and sophisticated newly created information.
The individuals in the population are on average going to carry a roughly stable load of harmful mutations, a roughly constant "cost" in harmful mutations. Individuals loaded with more than the average cost are generally going to die and remove a more-than-average load of harm out of the population pushing the average up, and individuals with a less than average load will multiply and pull the population average upwards. The cleansing effect of selection removing "damage" from the gene pool will automatically scale to offset the exact rate that mutation is causing "damage". Harm/cost/damage will be weeded out by selection at the same rate it is added by mutation. Neutral mutations will steadily accumulate in the library, and negative mutations will remain at a roughly fixed level constantly measured and scaled by the cost of each. Some mutations will dissappear while new ones appear.
The real power in evolution is the recombination. Every offspring contains a random mixture of mutations from that library. every offspring is a test case searching for a jackpot beneficial combination of mutations. Lets assume an individual has a million random mutations across its entire code. There are 500,000,000,000 mutation-pairs being simultaneously tested within that individual in parallel. Perhaps one is a mutation creating a toxin and another mutation for mutant skin pores. Either mutation alone may be harmful, but the pairing could be breakthrough protecting against predators.
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