Re: Evolution: A few questions

jason_r@www.wushuathletic.com wrote:
>Hi All,
>
>I stumbled upon this site last night and it seems that there are quite a
>few theistic evolutionists here (or is this group for theistic
>evolutionists?). If I had to classify myself, I'd say that I'm a
>progressive creationist -- I believe in an old earth holding the day/age
>view, etc. I'm skeptical (very skeptical?) of evolution, but I allow for
>the possibility of it. Anyway, maybe some theistic evolutionists here can
>provide some insight into some questions that I have (especially being
>that this list seems pretty civilized, as opposed to a lot of other
>message boards out there):

Hi, Jason

I'm in the process of slowly mutating from progressive creationist to
theistic evolutionist. I believe in an old earth and a day/age view of
Gen.1 and am very skeptical of the wider scope of the evolutionary
mechanisms. I consider all spontaneous-origin-of-life theories and most
of what is presented as origin-of-biological-information scenarios to be
speculative, up to now. But with the recent enormous increase in DNA
sequence data, a common descent of all species, including humans, now
seems to be proven beyond any reasonable doubt, if specifically
functionless features (not under _any_ selection pressure) are
considered. Thus: Has evolution occurred? Yes! Do we know how? No!

Does this mean that we have to postulate divine interventions? Surely,
God wants our decision for him to be voluntary, free, out of faith.
Therefore, I don't expect that there will ever be a scientific "proof of
God", as the Intelligent Design movement is trying to find (if
intelligent design in biology is necessary, either human or "natural"
extraterrestrial intelligences will never do - ultimately only God can
be an intelligent designer for life).

But God has plenty of opportunities to guide "natural" processes, such
as indeterminate outcomes of quantum events, to produce anything needed
in the biosphere, without science being able to trace it, even in
principle. I have called this God's "hidden options".

>1) Since evolution is not "conscious" how does it "know" that something is
>a benefit or a hinderance? The organism which experiences the change
>doesn't think, "Oh, wow, this <insert change> benefits my <insert feature>
>so I'm going to make sure I retain it!" And the process of evolution isn't
>isn't "conscious" so it doesn't consciously retain it, either. Or does it
>have to do more with the fact that the change isn't harmful to the
>organism (which would cause it to die without reproducing) therefore it's
>passed on? I imagine this is the case. If so, do we have any physical
>characteristics -- internal or external -- that developed by chance and
>that don't serve a purpose, but aren't harmful to survival, either so
>they're retained? I imagine organisms would randomly develop a number of
>these throughout the history of life.

We have lots of selectively neutral "building material" in our genomes,
which can be used by the process of evolution to "build" something
useful. Of course, it is under a constant turnover between being
produced by (random) mutations and being eliminated by (random) genetic
drift or occasionally by (randomly) acquired negatively selected
properties. The all-important question is the ratio of cases in which
such material accidentally acquires a positively selectable aspect and
the total neutral material. Tis ratio is completely unknown up to now,
so virtually all claims of spontaneous origins of truly novel
functionalities remain just-so stories. I don't call recombined
functional pieces of previously active molecules truly novel. It is true
that a given function can sometimes (often?) be performed by very
different sequences, i.e. molecular synonyms. But how often does this
occur? What we would need is a reasonable estimate of the density of
useful proteins (and/or RNAs) in the transastronomically huge sequence
space.

The spontaneous generation of information by means of natural selection
of random mutations does occur, but each such step of selection is just
a yes/no "answer" of the environment to the "question", "Is this ok?" of
the organism. The amount of information transferred from the environment
into the genome is 1 bit, at most, and fixation of any mutation in a
species is a very slow process. Considering the entire biosphere as a
unit: is this mechanism adequate to have produced our biosphere within
less than 4 billion years?

>2) What happens during the intermediary stages when a feature is evolving,
>but before it's fully functional? For example, I imagine it took an
>EXTREMELY long time before the wings of an insect or animal (which evolved
>from whatever they evolved from) were perfected and enabled them to fly.
>What happens during "however many generations" the organism exists with
>wings that were not yet functional? Wouldn't this be more detrimental thus
>causing the evolutionary process to drop the wings before they're useful?

Each macroscopic feature of an organism is the product of a large number
of genes interacting in a very complicated network of molecular
reactions. What changes by mutation are partial features of a molecule
(rather its gene), and what is selected are the viability and
reproducibility of the entire organism, and all such processes are
stochastic, in a very complex situation of a species in its environment.

This explains that now organs may very well be produced stepwise, and
through some intermediate functions, like the answers you already got
from others concerning wings. Another intermediate function for wings
would be gliding from trees, before full flight is possible, cf. e.g. Xu
X., Zhou Z., Wang X., Kuang X., Zhang F., Du X., "Four-winged dinosaur
from China", Nature 421 (2003), 335-340; Prum R.O., "Dinosaurs take to
the air", Nature 421 (2003), 323-324.

>3) My last question concerns non-theistic evolution -- the belief/theory
>that there's no God, that life occurred purely by chance, etc: The purpose
>of organisms is to survive and reproduce -- but why? If there's no purpose
>for existing and reproducing then what difference does it make if they do
>so or not? Why do organisms, from simple celled life-forms to plants to
>animals, have an innate need to survive and reproduce if there's no point
>to it?

Of course, non-theists say that there is no purpose. If there happens to
be (having evolved) a reproducing organism, it just reproduces, without
any purpose, and those that reproduce better will produce more
descendants, without any purpose. The same argument applies to the
origin of life: if there happens to occur a self-sustaining
autocatalytic chemical cycle, it just reproduces and increases. It all
reduces to the one question: why is there any life at all? We are back
to pure speculation - at least the non-theists.

>4) Ok, one last question :p . This is another one concerning non-theistic
>evolution and has to do with design -- specifically bodily symmetry. It's
>hard to understand how blind chance produced such a symmetrical body. Take
>the eyes for example. I followed a link from this list to
>http://www.genesisproclaimed.org/resources/articles/0018.htm . Under the
>progressive creationism section the article briefly describes how eyes may
>have evolved: "[A] few light-sensitive cells form an eyespot, the eyespot
>becomes recessed to increase the light-gathering area and to allow
>directional sense, the opening narrows to create a "pin-hole camera" eye,
>fluid fills the space for protection, the fluid becomes a lens." (the
>comment "the eyespot becomes recessed to increase the light-gathering
>area" makes it sound like it's a conscious decision, but I already asked
>about this in question 1). It's hard to understand how there just happened
>to be two areas containing light sensitive cells that were so
>symmetrically and "strategically" placed on the head. It seems more likely
>that organisms would have one eye on the side of the face, or two or three
>eyes placed randomly on the face. Another example are ears. I imagine the
>ears evolved in the same way the eyes did -- starting with an area of
>sound-sensitive cells. Again, though, it's so hard to imagine that two
>sound sensitive cell areas on the head happened to be so symmetrical --
>being at the same distance from the center of the head, the same distance
>from the top of the head, that they both evolved the exact same way, etc.
>It seems more likely that blind chance would result bodies being more
>asymmetrical and random. Can anyone comment on this?

As soon as you have at least two distinct body polarities in an organism
(i.e. head-to-tail and left-to right), the simplest forms of the
developmental program will produce left-right symmetry. What is more
difficult to produce is left-right asymmetry, e.g. for the position of
internal organs in vertebrates, cf. Monk N., "Asymmetric fixation",
Nature 427 (2004), 111-112; Denker H.W., "Early human development: new
data raise important embryological and ethical questions relevant for
stem cell research", Naturwissenschaften 91 (2004), 1-21.

>Oh, finally, does anyone have testimonies online? I'd be interested in
>reading how believers dealt with and reconciled evolution and the Bible
>including the fall of man, the introduction of sin into the world causing
>the need for a savior, etc. Like I said above, I'm skeptical of evolution,
>but I do allow for the possibility of it so I want to hear some thoughts
>from Christian evolutionists.
>
>I look forward to any resonses.
>
>
>Thanks a lot!
>Jason

About two years ago, someone asked whether those actively participating
on this list could provide their bio's. Various people did so. My bio
appeared on 8 Aug 2002. It should be in the list's archive,
http://www.calvin.edu/cgi-bin/archive

Peter

-- 
Dr. Peter Ruest, CH-3148 Lanzenhaeusern, Switzerland
<pruest@dplanet.ch> - Biochemistry - Creation and evolution
"..the work which God created to evolve it" (Genesis 2:3)