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How Lamarckian!

See also: Genomes 2nd Ed 2002, T. A. BROWN, Department of Biomolecular Sciences, Manchester UK 14.1. Programmed mutations? Excerpt

In 1988 startling results were published suggesting that under some circumstances Escherichia coli bacteria are able to mutate in a directed way that enables cells to adapt to an environmental stress. The randomness of mutations is an important concept in biology because it is a requirement of the Darwinian view of evolution, which holds that changes in the characteristics of an organism occur by chance and are not influenced by the environment in which the organism is placed. In contrast, the Lamarckian theory of evolution, which biologists rejected well over a century ago, states that organisms acquire changes that enable them to adapt to their environment. The Darwinian view requires that mutations occur at random, whereas Lamarckian evolution demands that programmed mutations occur in response to the environment.
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The results of Cairns et al. 1988 showed that when the lactose auxotrophs were plated onto a minimal medium containing lactose as the only sugar - circumstances that require that the bacteria must mutate into lactose prototrophs in order to survive - then the number of lactose prototrophs that arose was significantly higher than that expected if mutations occurred randomly. In other words, some cells underwent programmed mutation and acquired the specific change in DNA sequence needed to withstand the selective pressure.
Since 1988, a number of examples of what appear to be programmed mutations have been published, but the notion that bacteria, and possibly other organisms, can program mutations in response to environmental stress is by no means accepted by the scientific community. It is quite possible that these mutations will eventually be disproved or be shown to have an orthodox basis. However, until this happens we are left with the tantalizing possibility that even at this fundamental level our knowledge about genomes might be far from complete.

BTW, I think Dr. James Shapiro may have suffered the ideational flu of hubris regarding the over-generaity of his findings on rates of mutants in single cell organizisms -- more complex organisms have even more magnitudes of layers to fight off mutations. AND while the bacteria are singleton cell organisms, in many ways the very environment in which they grow acts as a sort of super-organism, and with that super-organism more layers of mutation-resitance. Shapiro's studies perhaps may have provided the very type of unrealistic forced lab environment most condusive to permitting mutations and encouraging the vitality of mutants.