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The
Atheist Devotional: Timeless Meditations for
the Godless by M. Moore
Copyright ã 2008 M. Previous: Reading Number 11: Dawkins: Blind Faith in a Blind Watchmaker
-Reading Number Twelve -
Dawkins: The Selfish—but Very Confused—Gene
Excerpted from: Dawkins, The Blind Watchmaker, Chapter 7*
The title of this reading is a play on the title of Dawkins’ book The Selfish Gene, in which he claims that all organisms, including we humans ourselves, are merely tools of our genes, nothing more than biological robots that our genes have created in order to propagate themselves. Just one more inspiring and uplifting thought to meditate on for us atheists. But now back to The Blind Watchmaker.
Natural selection selects genes for survival according to their fitness for their environment. “But from each gene's point of view, perhaps the most important part of its environment is all the other genes...in the cells of the successive individual bodies in which it finds itself.” A gene needs to be able to cooperate with the other genes it gets combined with as it is passed on through the generations.
In other words, genes should make some useful contribution. Genes for feathers wouldn’t be very welcome in a dolphin.
“...It is most directly seen in the case of biochemical pathways. ..suppose that Pathway 1 needs the succession of enzymes Al, Bl and Cl, in order to synthesize a desired chemical D, while Pathway 2 needs enzymes A2, B2 and C2 in order to arrive at the same desirable end-product.”
It’s so nice that that end-product is only “desirable,” and not indispensable to life—otherwise those organisms would have a tough time waiting around for the right enzymes to evolve! And I think we can confidently say that that most of our enzymes, and whatever other little doohickeys make up our bodies, are merely desirable and not essential, right? Of course.
...Whether evolution chooses Pathway 1 or Pathway 2 is a result of “each gene being selected by virtue of its compatibility with the other genes that already happen to dominate the population. If the population happens to be already rich in genes for Bl and Cl, this will set up a climate favouring the Al gene rather than the A2 gene.”
So A1 came to prominence because there were already a lot of B1 and C1 waiting around for it? But what were those two doing while they waited, since there was no A1 to complete the pathway? B1 and C1 must have served some purpose, otherwise they wouldn’t have evolved to the point of dominating the population. Well, they must have had some other job that was given them in the meantime, something to keep them busy until A1 came along. This we believe by faith.
“It will not be as simple as that, but you will have got the idea...”
Yeah, the idea being that I have to have a lot of blind faith in what people like Dawkins tell me.
The same applies to the genes that work together to make up things like eyes and ears and legs. “Genes for making teeth suitable for chewing meat tend to be favoured in a 'climate' dominated by genes making guts suitable for digesting meat.”
Sure, if there are a lot of meat-digesting guts around, then meat-chewing teeth would definitely come in handy! ...Unless, of course, plant-eating is being favored at that moment in “evolutionary history,” because meat is not readily available, but plants are. You just never know... And how did those guts get there in the first place, without the teeth already being there too? What good is a meat-digesting gut without meat-chewing teeth? Now if it was a gut that could digest both meat and plants, then maybe it could muddle along until the teeth arrived. But then there would be no clear preference for adaptations for meat-eating, since the gut can digest both meat and plants... Dawkins makes it sound so cut and dried until you really start to think about it. Maybe we atheists should just avoid thinking too much.
“But once one lineage had begun to build up a team of genes for dealing with meat rather than grass, the process was self-reinforcing.”
Um... in what way? If carnivorous genes have just “begun” to accumulate, that means there are still a lot of herbivorous genes around too (actually more of them than the carnivore genes that have just “begun” to build up). So any new gene coming along is going to be mighty confused about which “environment” it’s supposed to fit into: the herbivorous genes or the carnivorous ones! Well, maybe our confusion will clear up if we persevere. The story continues in the next reading. * “Excerpts” are paraphrased, except for “words in quotation marks and italics,” which are direct quotations from the excerpted work.
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