Since we have been talking about proteins, let’s back up to say a few things about their building blocks – the amino acids. Below is a figure of an amino acid.
Note the central carbon atom and how it is covalently bonded with four different groups. Three of these four groups are always the same in every amino acid used by life: the amino group (orange box), the carboxyl group (blue box), and the hydrogen atom. The R signifies the side chain, which differs for each amino acid.
Let me summarize some of the observations I have made with my recent focus on proteins and their role in the success of evolution. Consider the following:
To what degree is the design of a designer constrained by his/her building material? For example, imagine that we enlisted the service of the worlds most creative and brilliant engineers and tasked them to design a space craft that will carry men to Mars and back. Now, let’s add one constraint – the only material available to the designers is concrete. Would these brilliant designers be able to meet the design objective?
Below if a nice video about our modern understanding of evolution.
I especially enjoyed the comments from Sean Carroll (according to Michael Ruse, “Of all the scientists in the world today, there is no one with whom Charles Darwin would rather spend an evening than Sean Carroll.”):
So what this means is in some ways, some sense, evolution is a simpler process than we first thought. When you think about all of the diversity of forms out there, we first believed this would involve all sorts of novel creations, starting from scratch, again and again and again. We now understand that, no, that evolution works with packets of information and uses them in a new and different ways, and new and different combinations, without necessarily having to invent anything fundamentally new, but new combinations.
My, that’s a pretty radical change in the way we view evolution. The old way was far less friendly to teleology and also failed to prepare scientists for the more accurate understanding of evolution, an understanding that is now much more friendly to teleology.
This all raises some interesting questions. For example, without proteins, and their manufacturing process, what becomes of the blind watchmaker? Without proteins, and the latent functions contained within, might not the blind watchmaker exist as the impotent, crippled, blind watchmaker with no one to notice its existence? If so, how much credit does the blind watchmaker really deserve?
The vast and immense Tree of Life is a protein-dependent output. Point to
some evidence of evolution and I’ll point to the proteins that underlie it.
Without proteins, would there be a Tree of Life 3.5 billion years after the
RNA world took root? How do we know? If we believe so, would the Tree be
as immense and vast as it is today? A life form composed of nucleic acids,
carbohydrates, and lipids would suffice for the purposes of the blind
watchmaker. But could the blind watchmaker turn this material into
something that is analogous to an Ash tree filled with squirrels, beetles,
and birds?
Let’s get back to the observation that “most of the other known mechanisms of evolutionary change such as genetic drift, neutral mutation, gene duplications, transposons, horizontal gene transfer by plasmids, and others have no direction or goal at all and are in fact random.” As I explained, this is insufficient reason for declaring that evolution has no goal.
Nevertheless, some people may be troubled by the fact that the mechanisms of evolution are random (with regard to fitness). Not me.
All living things depend on proteins. Yet I sometimes wonder just how many people pause to consider just how amazing proteins are. Consider your own body. If you dig deep enough, it’s often as if a major organ system is centered around the function of a protein or small subset of proteins. Your muscles? Think of actin and myosin, the contractile proteins. Your brain and nerves? Think of the membrane receptors and channels that generate and transmit electrical signals. Your blood? Think of the hemoglobin that transports oxygen. Your digestive system? Think of the enzymes that break down all the food molecules (which, of course, include proteins). Your bones and joints? Think of collagen that binds things together. Your skin and hair? Think of that tough protein, keratin. Your glands? Think of hormones and the receptors that detect them. Your immune system? Think of the antibodies that guard your body.
See proteins as design material and suddenly you are struck by their immense versatility, as if they represent the ultimate, all-purpose substance for generating function.
They can generate light, detect light, or use light to generate ion gradients and chemical energy. They can act as a signal or detect a signal. They can impart movement and function as motors. You can use them to bind things together and to unbind things. They can be used to catalyze thousands of chemical reactions, transport tiny or bulky molecules, transmit signals across great distances, and/or proofread. They can exist as everything from a simple fiber to a complex, sophisticated molecular machine. They can function alone or as part of a circuit. Combine them with lipids, and you have a controllable barrier, perfect for compartmentalization. Combine them with DNA and you have a chromosome that can be regulated and packaged. Combine them with RNA and you have machines that can make proteins and perfectly splice genes. You can use them to evolve things, as the deeply influential processes of gene duplication, recombination, and horizontal gene transfer are dependent on, you guessed it, proteins. You can even use proteins to form the hard turtle shell, soft bunny fur, and the flight feathers of a duck.
In our science, there is no mention of, or mechanism for achieving, any long-term metaphysical or teological goals of form, complexity, or intelligence—as Gould has argued so eloquently. Most of the other known mechanisms of evolutionary change such as genetic drift, neutral mutation, gene duplications, transposons, horizontal gene transfer by plasmids, and others have no direction or goal at all and are in fact random (which natural selection is not) and therefore could not possibly give a particular direction to evolution.
Whenever someone says that something “could not possibly” happen, be careful, as the claim may be a cleverly disguised argument from ignorance. In this case, is it truly obvious that our understanding of evolution allows us to embrace the non-teleological perspective with such a sense of certainty?
Writing in the journal Outreach and Education in Evolution, David Zeigler asserts the following:
My “purpose” (we can create our own temporally and spatially limited purposes) in writing this piece is to point out one of the most important and real issues in the teaching of Darwinian evolution that so often goes unaddressed, or more amazingly—unrecognized, and this issue is really fairly obvious. Darwinian evolution by natural selection results in adaptations which increase the ability of the individuals to survive and reproduce successfully in their respective environments, or as biologists would say—adaptations increase the fitness of individuals. This is the only evolutionary goal or purpose for which science has found objective evidence.
In our science, there is no mention of, or mechanism for achieving, any long-term metaphysical or teological goals of form, complexity, or intelligence—as Gould has argued so eloquently. Most of the other known mechanisms of evolutionary change such as genetic drift, neutral mutation, gene duplications, transposons, horizontal gene transfer by plasmids, and others have no direction or goal at all and are in fact random (which natural selection is not) and therefore could not possibly give a particular direction to evolution. Numerous science writers have made the obvious point that had that asteroid not struck some 65,000,000 years ago and pushed the dinosaurs to extinction, we humans would undoubtedly not be here, for the evolution of mammals would have been constrained and altered drastically from what has come to pass (i.e., we humans were not destined to evolve).
I cite this because it is a nice, succinct description of the standard, non-teleological perspective shared by many. Yet how have teleologists reacted to this perspective?
May 17th, 2008 by 
Mike Gene 
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