Quotes 12-13-2013
by Miles Raymer
“Unlike mutation, the rapid acquisition of new, highly refined traits by acquisition and integration of former strangers confers immediate selective advantages on protoctist, plant, or animal captors. Often the association begins as predatory: One organism attempts to ingest and digest the other, which resists. The subdued prey or undigested bacterium leads to a trapped population. The inheritance of trapped populations, especially in the form of microbial genomes, creates novel evolutionary lineages that display genuinely new strategies worthy of study. Of course random mutations occur––in both predator and prey––and of course they are important aspects of the evolutionary process. But mutations refine and hone. In eukaryotes, by themselves, mutations do not create new species or important positive inherited variation. Genomes, on the other hand, come neatly packaged with long histories of heritable virtuosities and synthetic tricks. They provide just what is needed for an organism to change drastically and yet remain coherent and viable. Good documentation in the science literature shows that mobility, food-making ability, or novel metabolic traits (vitamin production, extraction of nitrogen from air, detoxification of oxygen) may be appropriated in toto, like skillful workers of a previous business brought on board by an acquiring corporation.
And just as a marriage or corporate merger cannot be simply reversed, evolution by genomic acquisition is an irreversible process. After integration of smaller genomes into those of the partner, the once-external genome can no longer be released back into nature. There comes a point in the relationship where the former free-living form cannot, by exercise of will, be rejected or ‘unacquired.’ Examples exist of the rejection of long-standing partners but they result in streamlined and altered new beings, not a reversion to past forms.”
––Acquiring Genomes: A Theory of the Origins of Species, by Lynn Margulis and Dorion Sagan, pg. 72-3
“‘We live in the flicker––may it last as long as the old earth keeps rolling! But darkness was here yesterday.'”
––Heart of Darkness, by Joseph Conrad, pg. 7
Woah.
“And just as a marriage or corporate merger cannot be simply reversed, evolution by genomic acquisition is an irreversible process. After integration of smaller genomes into those of the partner, the once-external genome can no longer be released back into nature. There comes a point in the relationship where the former free-living form cannot, by exercise of will, be rejected or ‘unacquired.’ Examples exist of the rejection of long-standing partners but they result in streamlined and altered new beings, not a reversion to past forms.”
THAT is an intense relationship analogy in science form. What a powerful metaphor! An irreversible process–the genome might continue to change, but it is impossible to return to the original form.
And as to the Heart of Darkness quote… Thank you for bringing it back to my attention. Beautiful.
This is quite the pairing today!