Science has determined that life arose and became complex through a process generally known as evolution, but biologists are engaged in an energetic debate about the form of that evolution. In essence, the argument centers on whether the biosphere should be characterized as a tree of life or an interactive web. In the tree construct, every living thing springs from a common ancestor, organisms evolve slowly by means of random mutations, and genes are passed on from parent to offspring (that is to say, vertically). The farther away from the common ancestor, generally speaking, the more complex the life-form, with humans at the apex of complexity.
The tree-of-life notion remains a reasonable fit for the eukaryotes, but emerging knowledge about bacteria suggests that the micro-biosphere is much more like a web, with information of all kinds, including genes, traveling in all directions simultaneously. Microbes also appear to take a much more active role in their own evolution than the so-called “higher” animals. This flies in the face of the more radical versions of Darwinism, which posit that the environment, and nothing else, selects genes, and that there is no intelligence, divine or otherwise, behind evolution — especially not in the form of organisms themselves making intentional changes to their heritable scaffolding. To suggest that organisms as primitive as bacteria are capable of controlling their own evolution is obviously silly.
Isn’t it?
I encourage you to read the article in full, but here's a bit more freakiness:
Bacteria, says Giovannoni admiringly, are marvels of engineering. “When it comes to biochemistry, they are much better than eukaryotes,” he says. “They don’t waste things. They’re very efficient, very clever. They keep it simple but very elegant and sophisticated.”
But just how smart are they, really?
Giovannoni stops short of claiming that bacteria are actually thinking. But the litany of bacterial talents does nibble at conventional assumptions about thinking: Bacteria can distinguish “self” from “other,” and between their relatives and strangers; they can sense how big a space they’re in; they can move as a unit; they can produce a wide variety of signaling compounds, including at least one human neurotransmitter; they can also engage in numerous mutually beneficial relationships with their host’s cells. Even more impressive, some bacteria, such as Myxococcus xanthus, practice predation in packs, swarming as a group over prey microbes such as E. coli and dissolving their cell walls.
At least one scientist was willing to allow for the possibility of bacterial thinking quite early in the development of microbiology: Alfred Binet, who invented the first reliable intelligence test and who published a book in 1888 called The Psychic Life of Microorganisms. And today the idea of thinking microbes is gaining ground. Marc van Duijn and colleagues at the University of Groningen in The Netherlands point out in the June 2006 issue of Adaptive Behavior that the presence of “the basic processes of cognition, such as perception, memory and action” in bacteria can now be “plausibly defended.” And bacteria that have antibiotic-resistance genes advertise the fact, attracting other bacteria shopping for those genes; the latter then emit pheromones to signal their willingness to close the deal. These phenomena, Herbert Levine’s group argues, reveal a capacity for language long considered unique to humans.
Whoa, as Keanu would say.
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And when we grow sick, that's simply the voice of the bacterium . . .
ReplyDeleteJeffery Hodges
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