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Saturday, 7 October 2017

Out of retirement:It's the blind watchmaker again.

Return of the Blind Watchmaker
Evolution News & Views 

Oh, the power of metaphor. Richard Dawkins's "blind watchmaker" is back, tinkering in his workshop to make timepieces of elegant craftsmanship. Xiaojing Gao and Michael Elowitz from Caltech begin a piece in the science journal Nature like this:

Living cells keep track of time with exquisite precision, despite using molecular components that are subject to unavoidable random fluctuations, known as noise. For example, natural circadian clocks can track the time of day, even in single-celled cyanobacteria. Such clocks have been selected over evolutionary timescales for their precision, and thus can be thought of as a literal embodiment of the biologist Richard Dawkins' 'blind watchmaker' -- his analogy for evolution's ability to produce systems with astonishing capabilities. However, evolution is not the only way to make a biological clock. The field of synthetic biology is based on designing artificial genetic circuits to implement new functions in living cells. Can a synthetic clock rival the precision of its naturally evolved counterparts? Potvin-Trottier et al. demonstrate on page 514 that even a relatively simple synthetic clock circuit can be astonishingly precise. [Emphasis added.]
Just how precise the synthetic clock is we shall see in a moment, but we need to draw some distinctions first. The passage above confuses two very, very different concepts: intentionally designed things and "naturally evolved" things. Gao and Elowitz personify "evolution" as a maker -- a watch maker -- an entity with ability ("evolution's ability") and goal-seeking behavior ("to produce systems"). And they say that natural circadian clocks are not just a virtual instance of this phantom personage; they are a "literal embodiment" of him (or her). They have ascribed personhood to the clocks!

For clarity, we need to understand that the natural designer in this picture is not just blind. The "blind watchmaker" is also deaf, dumb, unfeeling, un-tasting, non-smelling, unthinking, careless, senseless, and dead. A more accurate analogy we used previously is to picture dead athletes on a track needing to run the high hurdles -- mile-high hurdles at that. The gun fires! They're off! But they won't get over the first hurdle unless a volcano erupts or an asteroid hits to launch them randomly into the air. You get the picture; adding "evolutionary timescales" to allow for more volcanos and asteroid impacts isn't going to help.

One cannot emphasize enough the distinction between natural processes and intelligent processes. This is where Dawkins and so many other evolutionists go wrong. They look backward from the finish line, see the scores on the scoreboard, and assume Darwinian processes won the race. They go to the jewelry store and see watches of exquisite precision, and assume the blind watchmaker crafted them. What we need to do is take them back to the starting line and ask them, "Using only the tools in your materialistic philosophy, can you get to the finish line?"

In Illustra's new film Origin, Paul Nelson explains the limitations of scientific materialism. To be consistent, materialists need to adhere to their own rules.

When you come to the origin of life, the rules -- and this is not the science itself, this is the underlying philosophy -- the rules say to solve the problem you can use matter and energy and natural law, natural irregularities and chance processes -- but that exhausts your toolkit. What you're not allowed to use fundamentally by the rules -- so-called rules of science -- is mind or intelligence.
These rules apply not just at the origin of life. They apply throughout the evolutionary story. Natural selection doesn't add something to these rules. It, too, is blind, deaf, dumb, and dead. When Gao and Elowitz say that "Such clocks have been selected over evolutionary timescales for their precision," they sneak intelligence back into their workshop, looking back from the finished product and envisioning their phantom designer, the blind watchmaker, having done the designing work. They fall into the same conundrum that plagued Darwin: how do I use terms that avoid design? Darwin was fully aware of the implied intelligence in his phrase "natural selection." For subsequent editions of The Origin, he was influenced by his friends to substitute "survival of the fittest."

Staying consistent with scientific materialism is hard. But to maintain clarity in the Darwin vs design debate, we must insist our colleagues on the Darwinian side use only their own tools. The moment they sneak intelligence or mind into the picture, an umpire must call foul. One of Dr. Phillip Johnson's key roles in the ID movement was to play umpire, calling out Darwinians who merely assumed that natural processes were capable of creating things that look designed. "Darwinists know that the mutation-selection mechanism can produce wings, eyes and brains not because the mechanism can be observed to do anything of the kind," he said, "but because their guiding philosophy assures them that no other power is available to do the job" (Darwin on Trial, p. 115).

As Gao and Elowitz describe the clever molecular timepiece that Potvin-Trottier et al. built, we find goal-directing intelligence at work. Here we observe living, breathing, thinking watchmakers, living athletes at the starting line, ready to leap the hurdles.

The starting point for the authors' work is a synthetic oscillating genetic circuit called the repressilator, now 16 years old. The repressilator, along with a contemporaneous synthetic toggle switch, showed that new genetic circuits could be designed from modular genetic elements and their behaviour analysed in living cells. More specifically, it showed that a totally synthetic circuit could generate dynamic oscillations in protein expression, making bacterial cells 'blink' on and off through periodic synthesis of a fluorescent reporter protein.
It's clever work, no doubt about it. We see the biochemical engineers tinker with elements to achieve greater precision. At the end of the story, they proudly show off their molecular oscillator, built with genes in a bacterial plasmid.

All told, in the most precise of Potvin-Trottier and colleagues' circuits, the standard deviation in period length was reduced from 35% of the mean to around 14%, with strikingly uniform pulse shapes and amplitudes observed. This repressilator generates a pulse of fluorescent-protein expression just once every 14 generations. Assuming a cell-cycle time of 1 hour, it would take around 7.5 days, or 180 cell cycles, for a colony of cells to accumulate a standard deviation of half a period of drift. This extraordinary precision means that even a large population of cells can remain in sync.
Well, compared to living cells, which remain in sync forever and calibrate themselves to the diurnal cycle, seasonal cycles and annual cycles, perhaps they boast overmuch. But it's a start.

Evidently, precision does not necessarily demand circuit complexity and, in this case, even seems to benefit from minimalism.
Yet this minimalism required the concentrated effort of four biophysicists from Harvard and Cambridge. While the feedback loops employ a relatively simple "scissors-paper-rock" concept, each component is made of complex genes encoding specified information. Each response must trigger the appropriate follow-up action. The concentration of each gene product has to be calibrated. Additional components have to be inserted to buffer noise in the circuit. There's a whole lot of design going on here.

That we can now design cells to operate with remarkable precision in the face of noise suggests that synthetic biologists are starting to become pretty good watchmakers, after all.
That's precisely the point. At the end of Origin, Timothy Standish makes the proper inference with simplicity and clarity.

There is nothing magical about living things. I'm a scientist. I don't really believe in magic. I believe in mechanisms and causes that are sufficient to achieve the phenomena that I observe. Intelligence is sufficient. Intelligence is necessary. Therefore, intelligence is the conclusion that I come to.

We know of a cause that can design circuits of remarkable precision, robust to noisy environments. That cause is intelligence. Synthetic biologists have it. Watchmakers have it. But the toolkit of scientific materialism lacks this crucial element.

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