Re: [asa] (macroevolution) The term Darwinism Inference examples

>Recently one friend suggested the idea that we can't directly
observe El Paso from here (San Antonio), so how do we know just how far away
it really is unless we drive there.

George,
If he really believes that then he really ought to be an atheist, don't you
think? Unless he has direct experience with god every day.
So how did he react to your suggestion?

Anyway, the real question maybe is why do so many people come to be
Christians? The answer is not in experience. It is in inference.

-Dave

On Wed, Jul 8, 2009 at 2:39 PM, George Cooper <georgecooper@sbcglobal.net>wrote:

> Perhaps the most dramatic inference is found in the claim for black holes.
> How would anyone ever "see" such a beast? Yet, the evidence is substantial
> to demonstrate its existence.
>
> I am puzzled how some of my YEC friends can be intelligent and so
> anti-science. Recently one friend suggested the idea that we can't
> directly
> observe El Paso from here (San Antonio), so how do we know just how far
> away
> it really is unless we drive there. I was surprised but told him we could
> simply communicate with them and asking how high the Sun was, or a star if
> at night. Knowing this angular difference (compared to our measured
> altitude angle), the circumference of the Earth, and the rotation rate of
> the Earth (or universe for the Geocentrists), then we can easily calculate
> the distance.
>
> A counter example, however, might be how physicists see Hawking Radiation.
> Is it inferred? If so, based on what observations? How much hand-waving,
> if any, causes concern about certain claims being made from science. Of
> course, these scientists have the advantage, once they start making black
> holes, either way I won't be able to criticize them. :) [Not that I am
> actually doubting them, but there is a dramatic point here.]
>
> "Coope"
>
>
> Your exoplanet example, Bernie, is a nice one. There are about 10
> different
> ways exoplanets can be discovered based on substantial inference. [There
> are
> now at least four exoplanets out of 353 (currently)that have been directly
> observed, I think. Fomalhaut b had been inferred since 2005 based on the
> configuration of the star's dust belt. It was the first exoplanet seen
> (last November) in visible light (Hubble Telescope). The others were in IR
> (Keck & Gemini) also in Nov. 2008. Interestingly, for over 50 years
> exoplanets were sought by the method of astrometry, and they have now found
> their first exoplanet as of a month ago.]
>
>
>
>
> -----Original Message-----
> From: asa-owner@lists.calvin.edu [mailto:asa-owner@lists.calvin.edu] On
> Behalf Of Dehler, Bernie
> Sent: Wednesday, July 08, 2009 12:43 PM
> Cc: asa
> Subject: RE: [asa] (macroevolution) The term Darwinism
>
> I think one of the best examples of inferred things (vs. observed) relates
> to the super collider experiments. As I understand it, there are certain
> particles that are inferred to exist because they observe particles before
> the collision and see the ones after the collision- so the in-between
> particles are inferred to exist (they don't last long enough to observe
> directly).
>
> YEC's tend to go too far when they preach the "no one was there so no one
> knows" line of defense.
>
> Another example is to know there are planets circling a far away star,
> because the star has a certain wobble (can't see the planets directly).
>
> ...Bernie
>
> -----Original Message-----
> From: asa-owner@lists.calvin.edu [mailto:asa-owner@lists.calvin.edu] On
> Behalf Of Iain Strachan
> Sent: Wednesday, July 08, 2009 4:57 AM
> To: Cameron Wybrow
> Cc: asa
> Subject: Re: [asa] (macroevolution) The term Darwinism
>
> Cameron,
>
> I agree with you that "how it happened" is a very different question
> from "that it happened". But in your third paragraph, you seem to
> imply that the "that it happened" question is debatable because it is
> an inferred rather than an observed process.
>
> I think I differ here. Maybe it's because I always tend to think in
> terms of probabilities - I would say that making a (probabilistic)
> inference with a high degree of confidence is pretty much equivalent
> to observing (albeit indirectly).
>
> In my work, I have implemented a probabilistic technique for measuring
> Electrocardiogram (ECG) waveforms. Each beat of the heart on a normal
> ECG is divided up into a number of features (waves corresponding to
> waves of electrical activity on the heart), which are traditionally
> labelled P,Q,R,S and T, each caused by a different physiological
> process. If you look at a graph of the waveform, you can observe
> these directly by eye.
>
> But if one wants to automate this on a computer, one performs signal
> processing which makes the most probable inference as to which parts
> are P,Q, etc. These are known as "latent variables", ie. ones whose
> value has to be inferred rather than being directly measured. The
> final goal is to measure the length of time from the start of Q to the
> end of T, the QT interval, which is used in determining the cardiac
> safety of drugs. [ Some drugs cause a lengthening of this interval,
> leading to a risk of cardiac arrhythmia].
>
> Now, because it is a probabilistic technique, not only can it measure
> (by inference) where these points are, it can also give a "confidence
> measure". The technique is calibrated with a database of normal ECG
> waveforms. One can get low confidence (low probability) if, for
> example the ECG is corrupted by noise (such as bursts of interference
> when the subject moves). In such cases, one disregards the
> measurements made. But in high confidence, we can use the
> measurements.
>
> I would say that if the probability is high enough, that one has
> "observed" the QT interval. In fact our system measures it with a far
> greater degree of consistency than expert cardiologists doing it
> manually on screen.
>
> Hence the "inferred" value where the inference is made with a high
> degree of confidence is, I would say, equivalent to an "observed"
> value.
>
> By the same token, the ECG itself is an indirect measurement of the
> electrical waves that pass over the heart - they are not a direct
> observation of it. And yet a cardiologist can easily diagnose such
> conditions as atrial fibrillation, post myocardial infarction (heart
> attack) etc. simply by looking at the shape of the ECG. If, for
> example the segment from S to T is highly elevated with respect to the
> baseline, then one can "know" with a high degree of confidence, that
> the patient has suffered a heart attack.
>
> I think a better example of an "inferred process" which one can't
> verify is the inference of Dark Matter, which is used to explain the
> rotation curves of galaxies - dynamical simulation implies that there
> is not nearly enough (visible) matter to account for the data. Hence
> scientists infer the existence of "Dark Matter" which is completely
> invisible, in that it doesn't interact with EM radiation. Moreover,
> the inference is that there is much more of it than there is visible
> matter. But we don't know anything more about the Dark Matter, what
> it is, what kind of particles (various speculations have been made
> with fanciful names such as WIMPs and MACHOs) etc. Furthermore, it
> appears they would be extremely difficult to detect.
>
> Now I would have said that "knowing" is always probabilistic, and that
> Bernie's example of the chromosome fusion has a MUCH higher degree of
> confidence than I would put into the existence of Dark Matter. Indeed
> there are alternative theories that don't invoke Dark Matter, such as
> the Modification of Newtonian Dynamics (MOND).
>
> Now, one could argue that the chromosome fusion was down to God
> deciding to put two subroutines in the same file. But one doesn't
> have any evidence to support that one-off arbitrary act. (And one
> wonders why God might do something that looked like strong evidence of
> evolutionary processes).
>
> Iain
>
>
> On Wed, Jul 8, 2009 at 1:03 AM, Cameron Wybrow<wybrowc@sympatico.ca>
> wrote:
> > Bernie:
> >
> > Of course it is often possible to know that something happened without
> > knowing how it happened. Every time someone does a card trick for me, I
> can
> > never guess how they did it, but I know they did it.
> >
> > But do you understand the difference between an observed process and an
> > inferred one? If I observe a card trick, or a helicopter flying, or any
> > other process, then the question whether or not the process is occurring
> > does not arise. The only question that arises is how the trick was done,
> > how the helicopter flies, etc.
> >
> > Macroevolution, however, is not an observed but an inferred process.
> > Therefore, not only "how it happened" but "that it happened" are
> debatable
> > questions. Further, even granting "that it happened", macroevolutionary
> > theory does not merely infer a process but offers a mechanism to explain
> the
> > inferred process, and the two things are intrinsically tied together.
> Darwin
> > did not merely infer that macroevolution had taken place. Further, he
> > explicitly disclaimed any originality in making that inference. He
> > acknowledged that others had made that suggestion before him. He
> believed
> > that his original contribution was the *explanation* of the evolutionary
> > process -- i.e., accumulated tiny variations, pruned by natural
> selection.
> > Later evolutionary biologists have accepted Darwin's basic mechanism,
> > tweaking it with other purported mechanisms. But at the heart and core
> of
> > modern evolutionary theory is the mechanism, not the mere fact of change.
> It
> > is upon evolutionary biology's claim to have isolated the mechanism of
> > evolution that its claim to be scientific rests. Neither Darwin nor any
> > evolutionary biologist since would have thought his work scientifically
> > respectable if it amounted to a mere inference of the fact of common
> > ancestry (based on homology in morphology or genetics or fossils). They
> > have all believed that they know *that it happened* and *how it happened*
> in
> > a tightly integrated way.
> >
> > If I do not *know* that the alleged mechanisms -- Darwin's, or those of
> > later biologists -- can do what they are said to be able to do, then at
> most
> > I can know only that macroevolution has taken place by means unknown.
> But
> > to say that macroevolution took place by means unknown is not to offer a
> > scientific hypothesis. For all I know, God directed the transformations
> in
> > an entirely supernatural manner. Only if I provide a naturalistic
> mechanism
> > am I offering a scientific hypothesis. (To avoid unnecessary
> > side-controversy, I'm using the narrow definition of "scientific
> hypothesis"
> > generally accepted here.) But if I provide a naturalistic mechanism,
> then
> I
> > must provide evidence for the capability of the mechanism. I must show
> that
> > the suggested means can turn a Mesonyx into a whale, a fish into an
> > amphibian, a shrew into a primate, etc. I must have a detailed account
> of
> > the genetic mechanisms of normal inheritance, plus a detailed account of
> the
> > possibilities that arise in the case of mutation, and I must understand
> all
> > the phenotypical ramifications of possible genetic changes throughout the
> > length and breadth of the living world.
> >
> > In short, in evolutionary theory, it is useless merely to know "that it
> > happened". An evolutionary theory that cannot explain "how it happened"
> is
> > close to scientifically worthless. You are putting the emphasis on what
> is
> > the least important part of evolutionary theory from a scientific point
> of
> > view.
> >
> > So, now that I've answered your question, answer mine: how do you *know*
> > that the suggested mechanisms are capable of delivering the
> > macroevolutionary goods? How do you *know* that they can produce
> anything
> > beyond what field and laboratory science have observed, i.e., antibiotic
> > resistance in one-celled animals, and longer beaks or different
> coloration
> > in multi-celled animals?
> >
> > Cameron.
> >
> >
> >
> >
> > ----- Original Message ----- From: "Dehler, Bernie"
> > <bernie.dehler@intel.com>
> > To: "asa" <asa@calvin.edu>
> > Sent: Tuesday, July 07, 2009 6:05 PM
> > Subject: RE: [asa] (macroevolution) The term Darwinism
> >
> >
> >> Cameron:
> >> " My last note was two short paragraphs comprising eight sentences. Was
> >> that not short and concise enough for you?"
> >>
> >> No- that was perfect- thanks. I just meant to please do more of the
> same.
> >>
> >> Please briefly answer the question I gave you- a simple question to see
> if
> >> we agree or not. Here it is again, quoting myself:
> >>
> >> "It seems your whole point is to argue that macroevolution doesn't
> happen
> >> because we can't describe how it happens. If so, that is false logic.
> We
> >> know it happened because of the DNA evidence. You don't have to know
> HOW
> >> something happens in order to know that it DID happen. Do you
> understand
> >> this point? Do we have agreement on this point?"
> >>
> >> Once we understand each other on this point, I can then address your
> "how"
> >> questions.
> >>
> >> ...Bernie
> >>
> >> -----Original Message-----
> >> From: asa-owner@lists.calvin.edu [mailto:asa-owner@lists.calvin.edu] On
> >> Behalf Of Cameron Wybrow
> >> Sent: Tuesday, July 07, 2009 2:40 PM
> >> To: asa
> >> Subject: Re: [asa] (macroevolution) The term Darwinism
> >>
> >> Bernie:
> >>
> >> My last note was two short paragraphs comprising eight sentences. Was
> >> that
> >> not short and concise enough for you?
> >>
> >> I do not know that I can make myself clear to you, because you do not
> seem
> >> to have a natural bent toward fundamental philosophical questions, such
> as
> >> the question, "How do I know what I think I know?" But I will try, one
> >> last
> >> time.
> >>
> >> How do you *know* that Darwinian mechanisms -- or any set of
> naturalistic
> >> mechanisms (drift, or whatever else you want to throw in on top of
> >> Darwin's
> >> mechanisms) -- can take a bacterium without a flagellum and give it a
> >> flagellum? Or take a fish and turn it into an amphibian?
> >>
> >> How do you *know* that naturalistic mechanisms *alone* were responsible
> >> for
> >> the chromosome 2 "fusion event"? Can you give a complete mechanical
> >> account
> >> of the chromosome 2 "fusion event"? Can you explain how it happened in
> >> molecular terms? The electrostatic forces involved, etc.? Can you
> point
> >> me
> >> to an article written by anyone who has explained these things? If not,
> >> how
> >> do you *know* that such a fusion event is physically possible? If it is
> >> not
> >> physically possible, then your historical inference of its occurrence is
> >> invalid, and the similarity/difference between the genomes must have
> some
> >> other cause.
> >>
> >> In short, do you have any substantial conception in your mind regarding
> >> the
> >> "how" of macroevolutionary change, or do you have only a vague
> conception
> >> of
> >> sequential transformations, and just take it on faith that the
> >> evolutionary
> >> biologists have worked out the details somewhere, perhaps in some
> obscure
> >> technical journals in the back of the Stanford or M.I.T. library?
> >>
> >> And if you don't have any substantial conception in your mind of the
> "how"
> >> of macroevolutionary change, why do you believe that the mechanisms
> >> proposed
> >> are adequate? Because the consensus of biologists tells you so?
> >>
> >> Cameron.
> >>
> >>
> >> ----- Original Message -----
> >> From: "Dehler, Bernie" <bernie.dehler@intel.com>
> >> To: "asa" <asa@calvin.edu>
> >> Sent: Tuesday, July 07, 2009 5:03 PM
> >> Subject: RE: [asa] (macroevolution) The term Darwinism
> >>
> >>
> >>> Cameron- please be short and concise- why do you need to know the
> >>> mechanisms for macro-evolution?
> >>>
> >>> Is it to convince you that macroevolution occurs? If you are looking
> for
> >>> evidence that macroevolution actually happened- it is plain in the DNA
> >>> record.
> >>>
> >>> If you want to know exact ways macroevolution happened, one thing that
> >>> Dr.
> >>> Campbell mentioned is that it can take millions of years and so it is
> >>> hard
> >>> to piece together. There are some things we can't comprehend because
> of
> >>> vast scales of time and/or distance involved- however, we have the
> >>> evidence that it actually happened.
> >>>
> >>> It seems your whole point is to argue that macroevolution doesn't
> happen
> >>> because we can't describe how it happens. If so, that is false logic.
> We
> >>> know it happened because of the DNA evidence. You don't have to know
> HOW
> >>> something happens in order to know that it DID happen. Do you
> understand
> >>> this point? Do we have agreement on this point?
> >>>
> >>> Cameron said:
> >>> "My question is: "Supposing that macroevolution occurred, can it
> >>> be explained *entirely* by chance and necessity, or does it *also*
> >>> require
> >>> the input of intelligence?" (which is the ID/Darwinist debate)"
> >>>
> >>> Don't you think that aspects of 'natural selection' also involve
> >>> intelligence, on the part of animals? For example, animals (and humans)
> >>> may select mates based on their thinking (which is intelligence). The
> >>> 'intelligence' component depends on the complexity of the organisms.
> The
> >>> component is extremely high with humans (including genetic
> engineering),
> >>> and low (non-existent) with plant life.
> >>>
> >>> ...Bernie
> >>>
> >>> PS: thanks for the short reply.
> >>>
> >>> -----Original Message-----
> >>> From: asa-owner@lists.calvin.edu [mailto:asa-owner@lists.calvin.edu]
> On
> >>> Behalf Of Cameron Wybrow
> >>> Sent: Tuesday, July 07, 2009 1:30 PM
> >>> To: asa
> >>> Subject: Re: [asa] (macroevolution) The term Darwinism
> >>>
> >>> Bernie:
> >>>
> >>> I did not speak of "believing in macroevolution". I asked for a
> detailed
> >>> genetic pathway -- even a merely hypothetical pathway -- for any major
> >>> change in organs, systems, etc. I said that I have seen no such
> pathway
> >>> provided in the evolutionary literature.
> >>>
> >>> My question is not: "Did macroevolution occur?" (which is the YEC/TE
> >>> debate). My question is: "Supposing that macroevolution occurred, can
> >>> it
> >>> be explained *entirely* by chance and necessity, or does it *also*
> >>> require
> >>> the input of intelligence?" (which is the ID/Darwinist debate) The
> >>> genetic
> >>> evidence that you cite merely provides more evidence that
> macroevolution
> >>> has
> >>> occurred, or at best, that *some* of its causes are contingent
> >>> (accidental
> >>> fusing of chromosomes, etc.). It does not provide anywhere near a full
> >>> or
> >>> convincing account of the construction of major new organs or body
> plans
> >>> via
> >>> Darwinian means, or any other set of naturalistic means. When you find
> >>> an
> >>> evolutionary book that does this, let me know and I will read it.
> >>>
> >>> Cameron.
> >>>
> >>>
> >>>
> >>> ----- Original Message -----
> >>> From: "Dehler, Bernie" <bernie.dehler@intel.com>
> >>> To: "asa" <asa@calvin.edu>
> >>> Sent: Tuesday, July 07, 2009 12:20 PM
> >>> Subject: RE: [asa] (macroevolution) The term Darwinism
> >>>
> >>>
> >>>> Cameron said:
> >>>> "My point exactly. And the logical follow-up question is: if
> >>>> evolutionary biologists are lacking the above knowledge, how can they
> be
> >>>> so *certain* that microevolutionary processes can simply be
> extrapolated
> >>>> to generate macroevolution?"
> >>>>
> >>>> You don't need to extrapolate to believe in macroevolution. The
> >>>> evidence
> >>>> is in DNA (pseudogenes and fused chrpomosome #2) that humans evolved
> >>>> from
> >>>> apelike animals- that is macroevolution. Because of this DNA
> evidence,
> >>>> one can be certain.
> >>>>
> >>>> ...Bernie
> >>>>
> >>>> -----Original Message-----
> >>>> From: asa-owner@lists.calvin.edu [mailto:asa-owner@lists.calvin.edu]
> On
> >>>> Behalf Of Cameron Wybrow
> >>>> Sent: Monday, July 06, 2009 9:40 PM
> >>>> To: asa
> >>>> Subject: Re: [asa] The term Darwinism
> >>>>
> >>>> David:
> >>>>
> >>>> Your eloquent answer below makes my point far better than I could have
> >>>> made
> >>>> it.
> >>>>
> >>>> You have in essence argued that we cannot give full evolutionary
> >>>> pathways --
> >>>> not even full hypothetical evolutionary pathways -- for major organs
> and
> >>>> systems, for several reasons, notably (1) we simply do not yet have
> the
> >>>> understanding of the genome necessary for the task, and (2) we cannot
> >>>> reconstruct the environments accurately enough to be sure how
> selection
> >>>> would have operated.
> >>>>
> >>>> My point exactly. And the logical follow-up question is: if
> >>>> evolutionary
> >>>> biologists are lacking the above knowledge, how can they be so
> *certain*
> >>>> that microevolutionary processes can simply be extrapolated to
> generate
> >>>> macroevolution? It is one thing to say that macroevolution *may* be
> >>>> explicable via roughly Darwinian processes; it is another thing
> entirely
> >>>> to
> >>>> say that "science" has proved this, or that the extrapolation is so
> >>>> unproblematic it does not even need to be critically analyzed.
> >>>>
> >>>> Yes, a rudimentary version of an eye which actually *works* (however
> >>>> poorly), might be useful (e.g., a crude, light-sensitive spot on a
> >>>> one-celled creature), but an eye which depends on an arrangement of
> >>>> complicated parts (iris, cornea, retina, various fluids, a whole bunch
> >>>> of
> >>>> co-ordinated muscles, etc.), but is missing some of those parts or has
> >>>> some
> >>>> of those parts broken (so that the whole system cannot work) would not
> >>>> be
> >>>> useful. A computer with a keyboard which could only type the letter
> "e"
> >>>> would be useless for word-processing, for example, even though all the
> >>>> other
> >>>> components of the computer worked just fine. So anyone who believes
> >>>> that
> >>>> macroevolution produced the human camera eye must propose intermediate
> >>>> stages, describing all the organ parts necessary to each of those
> >>>> intermediate stages, and must also propose mutations that would allow
> >>>> one
> >>>> stage to progress to the next one, retaining all or most of the old
> >>>> function
> >>>> while adding new elements that would eventually lead to the new and
> >>>> improved
> >>>> function. So if the stages of the eye went from, say, 3 interacting
> >>>> parts,
> >>>> to 7 interacting parts, to 13 interacting parts, to 22 interacting
> >>>> parts,
> >>>> etc., a macroevolutionary account would set forth each of these stages
> >>>> in
> >>>> a
> >>>> separate chapter of a book, describing them anatomically and
> >>>> functionally,
> >>>> explaining the genetic basis of each stage, and then proceeding to
> >>>> explain
> >>>> the transition to the next stage. There would need to be as many
> >>>> chapters
> >>>> in the book as there were hypothetical stages. But this is not the
> way
> >>>> evolutionary biology is ever written. Or if it is written in this
> way,
> >>>> I
> >>>> have yet to see any examples.
> >>>>
> >>>> Regarding your final analogy, note that the question, "When Sally
> threw
> >>>> the
> >>>> ball on this particular date, where did it go?", contains a built-in
> and
> >>>> unproved assumption, i.e., that Sally in fact threw a ball. If we
> take
> >>>> "Sally" to be an analogue of "macroevolutionary processes", then we
> see
> >>>> the
> >>>> unstated assumption of macroevolutionary theory, i.e., that there
> exist
> >>>> entirely natural processes of biological change capable of building
> >>>> radically new organs and body plans. Yet if all we know is that
> >>>> macroevolution *happened*, but cannot account for *why* it happened,
> >>>> then
> >>>> it
> >>>> is premature to assume that the causes of the process were entirely
> >>>> natural.
> >>>> It is the presumption (without proof) that the causes of the process
> >>>> were
> >>>> wholly natural that ID proponents greet with skepticism. How can we
> >>>> know
> >>>> this, given the huge gaps in our understanding -- gaps just conceded
> by
> >>>> you -- regarding what genes control the various structures and
> >>>> functions?
> >>>> Wouldn't it be a more accurate -- not to mention scientifically modest
> >>>> --
> >>>> statement of our current knowledge to say that there *may* be a wholly
> >>>> naturalistic explanation for the fossil record, but that we are
> nowhere
> >>>> near
> >>>> having such an explanation in hand?
> >>>>
> >>>> Cameron.
> >>>>
> >>>> ----- Original Message -----
> >>>> From: "David Campbell" <pleuronaia@gmail.com>
> >>>> To: "asa" <asa@calvin.edu>
> >>>> Sent: Monday, July 06, 2009 2:56 PM
> >>>> Subject: Re: [asa] The term Darwinism
> >>>>
> >>>>
> >>>>>> 2. The reason I suggested a 500-page book is that 500 pages is the
> >>>>>> minimum that would be needed to document the changes for any major
> >>>>>> organ
> >>>>>> or system. Every step of the way -- and there would be hundreds of
> >>>>>> steps -- would need diagrams of the genome with explanations of the
> >>>>>> substitutions or deletions, diagrams of the proposed physiological
> >>>>>> changes corresponding to the genomic changes, a discussion of the
> >>>>>> environmental aspects (selection pressures acting on each change,
> >>>>>> etc.),
> >>>>>> and so on. I do not find it surprising that such detailed works
> have
> >>>>>> not
> >>>>>> appeared, as I believe that Darwinian explanation is mostly
> >>>>>> speculation,
> >>>>>> ad hoc non-mathematical reasoning, and bluff.<
> >>>>>
> >>>>> A more important reason for the absence of such works is that it is
> >>>>> technologically impossible. Such a description would only be
> possible
> >>>>> if we had full knowledge of all the genes influencing whatever
> >>>>> feature/organism and their exact functions. Bacterial genome
> >>>>> sequences were big news less than two decades ago; sequences were big
> >>>>> news three decades ago; computer power is also dramatically
> >>>>> increasing. The general coverage of genomic sequencing across the
> >>>>> eukaryotes is still very poor, and even in well-studied model
> >>>>> organisms such as fruit flies, humans, mice, nematodes, or yeast we
> >>>>> don't know what every gene does (particularly given that "gene" must
> >>>>> include stuff like microRNA, not just enzymes). There is rapid
> >>>>> progress ongoing in the field, and these data may be possible to
> >>>>> obtain before long, but at present it's just not possible.
> >>>>>
> >>>>> Even with full details on the living things, this does not give us
> all
> >>>>> the information that we would want about what happened in the past.
> >>>>> Gene sequences for ancestors can be modeled by comparing the
> sequences
> >>>>> in descendents and reconstructing a plausible ancestral form. This
> is
> >>>>> especially promising in cases where we have a good idea of the
> >>>>> ancestral function of a gene, e.g. where a gene unique to a
> particular
> >>>>> group of organisms shows similarity to another gene from a more
> >>>>> inclusive group of organisms, it's likely that the unique gene arose
> >>>>> from an ancestral form of the other. Such studies have been done for
> >>>>> a few specific genes.
> >>>>>
> >>>>> There are also a few credible reports of fossils preserving evidence
> >>>>> of molecular sequences, as well as a lot of non-credible ones.
> (Amber
> >>>>> seals water in, which is bad for DNA.) However, these will very
> >>>>> probably be limited to fairly durable molecules, especially ones
> >>>>> closely associated with hard parts.
> >>>>>
> >>>>> Reconstruction of past conditions can be done with varying degrees of
> >>>>> precision, depending on the quality of the fossil record. However,
> >>>>> exaptation shows that it's hard to be absolutely certain what the
> >>>>> precise selective factors involved in a particular situation might
> be.
> >>>>> Also, some key elements of the environment do not preserve well
> >>>>> (e.g., soft-bodied organisms, exact weather, regional-scale
> >>>>> geography), just as some environments do not preserve well.
> >>>>>
> >>>>> Yet another factor is that the market for such research is generally
> >>>>> poor. There are some applications to medical and biotechnical
> fields,
> >>>>> but as a whole it's entirely up to academia. Even within academia,
> >>>>> there's not nearly as much support for "academic" research as there
> is
> >>>>> for research that can bring in lots of money from medical or biotech
> >>>>> or even agricultural grants. The number of job postings for
> >>>>> paleontology or evolutionary biology is quite low, especially if you
> >>>>> remove positions for students to work on evolution within a model
> >>>>> organism or pathogen from the tally. (I'm also not counting "we want
> >>>>> someone to teach premedical courses and maybe do the evolution course
> >>>>> on the side.")
> >>>>>
> >>>>> Of course, anyone is free to set a level of proof desired for
> >>>>> something, but it is unreasonable to expect such a book to already be
> >>>>> available.
> >>>>>
> >>>>> That's not to say that we can't trace the basic evolution of a
> >>>>> particular organism or feature with a fair amount of detail. Eyes,
> >>>>> for example, are rather easy to explain. Plenty of organic molecules
> >>>>> absorb certain types of electromagnetic radiation, so finding
> >>>>> light-sensitive pigments is not too hard. Being able to detect and
> >>>>> respond to light levels is generally useful (e.g., getting light for
> >>>>> photosynthesis or keeping in the shadow to hide from heat, UV,
> >>>>> predators, etc.). Even a rudimentary version is useful. Increasing
> >>>>> complexity of the visual system is generally advantageous, so a
> >>>>> gradual accumulation of improvments is quite unsurprising. Details
> of
> >>>>> the color vision system in humans and related primates has been
> >>>>> studied in detail, since we have relevant gene sequences and a model
> >>>>> system in the South American monkeys, which are generally red/green
> >>>>> colorblind. On the other hand, people with all sorts of vision
> >>>>> deficiencies can function reasonably well-any problems with the
> system
> >>>>> are not automatically fatal.
> >>>>>
> >>>>> Much of the evolution of the bivalve shell can be traced in detail.
> >>>>> Although genetic work is relatively limited, we do have good general
> >>>>> phylogenies of the group and some genetic data on some of the
> proteins
> >>>>> involved in early development of the shell. We can also trace the
> >>>>> origin of the bivalved shell from a single shell in the fossil
> record,
> >>>>> and we can trace changes in shell structure and form through the
> >>>>> fossil record.
> >>>>>
> >>>>>> even when 150 years later it still can't take us from point A to
> point
> >>>>>> B
> >>>>>> in detail, as virtually all other sciences can.<
> >>>>>
> >>>>> Actually, it's probably about on par with physics in this regard.
> >>>>> There are two major differences in the types of questions being asked
> >>>>> that make the comparison misleading.
> >>>>>
> >>>>> First, in evolution we are generally interested in a very complex
> >>>>> system. Even a very well characterized system like gravity can
> become
> >>>>> unsolvable in detail when you are dealing with three or more objects.
> >>>>> Many of the factors involved in evolution are well-characterized
> >>>>> mathematically, but many are either probabilistic or not readily
> >>>>> quantified. If you have a very simple system, then we can make
> rather
> >>>>> accurate and precise evolutionary predictions. Secondly, most
> >>>>> interest in evolution is in reconstructing the history of
> life-exactly
> >>>>> what happened in a specific example in the distant past-rather than a
> >>>>> general statement of average behavior of biological systems. Instead
> >>>>> of the intro physics question of "if you throw a ball with a certain
> >>>>> force and angle and ignore everything except earth's gravity, what
> >>>>> would hapen?", we are asking questions more like "When Sally threw
> the
> >>>>> ball on this particular date, where did it go?"
> >>>>>
> >>>>> --
> >>>>> Dr. David Campbell
> >>>>> 425 Scientific Collections
> >>>>> University of Alabama
> >>>>> "I think of my happy condition, surrounded by acres of clams"
> >>>>>
> >>>>>
> >>>>> To unsubscribe, send a message to majordomo@calvin.edu with
> >>>>> "unsubscribe asa" (no quotes) as the body of the message.
> >>>>>
> >>>>
> >>>>
> >>>> To unsubscribe, send a message to majordomo@calvin.edu with
> >>>> "unsubscribe asa" (no quotes) as the body of the message.
> >>>>
> >>>>
> >>>> To unsubscribe, send a message to majordomo@calvin.edu with
> >>>> "unsubscribe asa" (no quotes) as the body of the message.
> >>>>
> >>>
> >>>
> >>> To unsubscribe, send a message to majordomo@calvin.edu with
> >>> "unsubscribe asa" (no quotes) as the body of the message.
> >>>
> >>>
> >>> To unsubscribe, send a message to majordomo@calvin.edu with
> >>> "unsubscribe asa" (no quotes) as the body of the message.
> >>>
> >>
> >>
> >> To unsubscribe, send a message to majordomo@calvin.edu with
> >> "unsubscribe asa" (no quotes) as the body of the message.
> >>
> >>
> >> To unsubscribe, send a message to majordomo@calvin.edu with
> >> "unsubscribe asa" (no quotes) as the body of the message.
> >>
> >
> >
> > To unsubscribe, send a message to majordomo@calvin.edu with
> > "unsubscribe asa" (no quotes) as the body of the message.
> >
>
>
>
> --
> -----------
> Non timeo sed caveo
> (\__/)
> (='.'=)
> (")_(") This is a bunny copy him into your signature so he can gain
> world domination
> -----------
>
>
> To unsubscribe, send a message to majordomo@calvin.edu with
> "unsubscribe asa" (no quotes) as the body of the message.
>
>
> To unsubscribe, send a message to majordomo@calvin.edu with
> "unsubscribe asa" (no quotes) as the body of the message.
>
>
> To unsubscribe, send a message to majordomo@calvin.edu with
> "unsubscribe asa" (no quotes) as the body of the message.
>

To unsubscribe, send a message to majordomo@calvin.edu with
"unsubscribe asa" (no quotes) as the body of the message.
Received on Wed Jul 8 16:11:35 2009