dubois@uwmacc.UUCP (Paul DuBois) (04/28/85)
> In article <330@iham1.UUCP> rck@iham1.UUCP writes: >> >> >> THE SCIENTIFIC CASE FOR CREATION: 116 CATEGORIES OF EVIDENCE >> >> I. (Life Sciences): THE THEORY OF ORGANIC EVOLUTION IS INVALID. >> >> A. EVOLUTION HAS NEVER BEEN OBSERVED. >> >> 6. No known mutation has ever produced a form of life having >> both greater complexity and greater viability [a,b] than >> any of its ancestors [c-f]. > [Stanley Friesen] > Incorrect, mainly because increased viability is a function of > envitonment. A mutant that is disadvantagous in one enviromnment may > be advantageous or even necessary in another. For instance the > vestigial-wing mutant in fruit flies. This form cannot fly, and under > standard lab conditions it does not breed well, since "normal" fruit > flies prefer to mate with other "normal" flies. *But*, when a styeady, > high wind is present "normal" flies are blown away by the wind; the > vestigial-wing, flightless flies are *not*, thus they are the *only* > ones to breed. This is *clearly* greater viability in this environment. You give an example of a mutation which leads to loss of a morphological character. If evolution proceeds on the basis of loss of function, I would not wish to place much confidence in it. Where are the new and useful characteristics? Also, it would appear that a mutation such as the example given is not really a serious entry for consideration. If it was really more greatly viable, natural selection would result in it being found in wild form, right? (Otherwise natural selection doesn't work.) Is it found? I suppose it might be, but since you talk about "standard lab conditions", I am led to think otherwise... -- | Paul DuBois {allegra,ihnp4,seismo}!uwvax!uwmacc!dubois --+-- | "There are two sides to every argument, until you take one." |
rlh@cvl.UUCP (Ralph L. Hartley) (04/29/85)
> You give an example of a mutation which leads to loss of a > morphological character. If evolution proceeds on the basis of loss > of function, I would not wish to place much confidence in it. Where > are the new and useful characteristics? How about resitance to DDT? > Also, it would appear that a mutation such as the example given is not > really a serious entry for consideration. If it was really more > greatly viable, natural selection would result in it being found in > wild form, right? (Otherwise natural selection doesn't work.) Is it > found? I suppose it might be, but since you talk about "standard lab > conditions", I am led to think otherwise... WAIT A COTTON PICKIN MINUTE! If no improved mutations occur, then ther is no basis for evolution. If improved mutations DO occur, natural selection dosn't work (because the change should have taken place in the wild). You can't have it both ways. Ralph Hartley rlh@cvl
mrh@cybvax0.UUCP (Mike Huybensz) (04/29/85)
> [Paul DuBois to Stanley Friesen] > You give an example of a mutation which leads to loss of a > morphological character. If evolution proceeds on the basis of loss > of function, I would not wish to place much confidence in it. Where > are the new and useful characteristics? Numerous mutations have been found in Drosophila which add morphological characters. There are genes that can cause formation of a second pair of wings out of what would have been calypters, genes that can cause formation of legs out of antennae, and genes that can cause formation of extra bristles. Conceiveably, these could be useful characteristics in some environment. Natural selection could then modify the new structures to more specialized forms. > Also, it would appear that a mutation such as the example given is not > really a serious entry for consideration. If it was really more > greatly viable, natural selection would result in it being found in > wild form, right? (Otherwise natural selection doesn't work.) Is it > found? I suppose it might be, but since you talk about "standard lab > conditions", I am led to think otherwise... It's been well known for about a century that flightless forms are most frequently found on islands. Birds and insects come readily to mind. -- Mike Huybensz ...decvax!genrad!mit-eddie!cybvax0!mrh
ward@hao.UUCP (Mike Ward) (04/30/85)
> Also, it would appear that a mutation such as the example given is not > really a serious entry for consideration. If it was really more > greatly viable, natural selection would result in it being found in > wild form, right? (Otherwise natural selection doesn't work.) Is it > found? I suppose it might be, but since you talk about "standard lab > conditions", I am led to think otherwise... We seem to be changing the rules here. Now it is not only neccessary to observe evolution happening, but we must observe the exact changes that already occured in nature? An evolutionary change is an evolutionary change. The conditions created in a laboratory are not likely to generate a change that would be found in nature. The expense involved in setting up a natural environment, then ensuring that populations remained pure, would be enormous. I doubt that anyone would go to the trouble, just to satisfy a few people whose religion would prevent them from accepting the evidence anyhow.
keithd@cadovax.UUCP (Keith Doyle) (04/30/85)
[..................]
Ok, I'd like to tirade a bit about mutations. Several people on the net
seem to think that the only way evolution could occur is via major mutations
that generate wonderful new features (*poof* instant wings!). Actually,
partially due to the fact that evolution seems to take millions of years,
slight mutations are probably more useful than gross ones. An example
might be a bird who feeds on insects that like to hide in certain flowers.
Any time a bird is born with slight mutations that cause a slightly longer
beak, this bird might have a better chance of survival if the food supply
is otherwise low. Initially, perhaps this new characteristic is not
a significant enough improvement so that all other bird die out, so our
mutant bird mates with a normal bird. The offspring then becomes a
'carrier' if you will, of this longer beak gene. Over a some period
of time, enough of these genes may accumulate so that the entire general
population has 'evolved' longer beaks. A similar situation has been proposed
as having happened to the moth which has changed its color for camoflage.
There's no particular reason to think that these type of cumulative effects
are prohibited from changing a snake into a lizard, a fish into a frog,
etc. given enough time. Many mutations may be minimal to the point of being
unnoticed. And in fact mutations may not be uncommon. In addition, it may
be possible for a certain mutation to occur that has several effects, some
positive and some negative for a certain environment. If the environment
suffers a significant change, it may be that a large part of the general
population might die out, thus leaving only a few organisms who have
accumulated certain 'mutant' characteristics. Thus, these characteristics
could effectively become the 'status quo' in very few generations. And,
it may be possible for a positive mutant 'trait' to carry with it some
negative 'trait'.
What I'm really trying to get at though, is that not all mutations are
dramatic and debilitating. In fact, I think you'll find that mutation is
going on all the time, most of them having very minor effects that
accumulate over time.
Keith Doyle
# {ucbvax,ihnp4,decvax}!trwrb!cadovax!keithdgordon@uw-june (Gordon Davisson) (05/14/85)
>>>[rck@iham1.UUCP] >>> THE SCIENTIFIC CASE FOR CREATION: 116 CATEGORIES OF EVIDENCE >>> >>> 6. No known mutation has ever produced a form of life having >>> both greater complexity and greater viability [a,b] than >>> any of its ancestors [c-f]. >> [Stanley Friesen] >> Incorrect, mainly because increased viability is a function of >> envitonment. A mutant that is disadvantagous in one enviromnment may >> be advantageous or even necessary in another. For instance the >> vestigial-wing mutant in fruit flies. This form cannot fly, and under >> standard lab conditions it does not breed well, since "normal" fruit >> flies prefer to mate with other "normal" flies. *But*, when a styeady, >> high wind is present "normal" flies are blown away by the wind; the >> vestigial-wing, flightless flies are *not*, thus they are the *only* >> ones to breed. This is *clearly* greater viability in this environment. > [Paul DuBois] > You give an example of a mutation which leads to loss of a > morphological character. If evolution proceeds on the basis of loss > of function, I would not wish to place much confidence in it. Where > are the new and useful characteristics? Patience, patience. The vestigial-wing mutation is just one of the possible mutations which are advantageous in the new environment. Since it is a reasonably common mutation, one would expect it to happen soon, and then spread through the population. Other, less common, newly advantageous mutations are likely to take longer to occur. Let me try to generalize this: if a reasonably homogenous population is subjected to an environment somewhat different from the one if is adapted for, it will evolve in 2 ways: by loosing newly disadvantageous traits, and by gaining newly advantageous traits. (this is an oversimplification, but bear with me) I would expect that, in general, loosing a particular trait is more likely than gaining a particular new trait, because there is a fixed supply of old traits to loose, and an unlimited supply of new traits to choose from. (is this actually true? References, anyone?) Since adaptations tend to happen in order of likelyhood (simple probability here), the population will first loose complexity, then gain it back, but differently. Complexity, in this context, will have to stay fuzzily defined until we (I) learn more about genetic coding. Has anyone else proposed the above, or is it original (or wrong)? Your comments are solicited. > Also, it would appear that a mutation such as the example given is not > really a serious entry for consideration. If it was really more > greatly viable, natural selection would result in it being found in > wild form, right? (Otherwise natural selection doesn't work.) Read what he said, Paul. "Increased viability is a function of environment. A mutant that is disadvantagous in one enviromnment may be advantageous or even necessary in another." The vestigial-wing mutant is more viable under the experimental conditions, but less viable under most/all "natural" conditions. No contradiction here. > Is it > found? I suppose it might be, but since you talk about "standard lab > conditions", I am led to think otherwise... I would expect it to be found, but very rarely. (You see, they aren't very reproductively successful, and they die off just as fast as they mutate in) -- Human: Gordon Davisson ARPA: gordon@uw-june.ARPA UUCP: {ihnp4,decvax,tektronix}!uw-beaver!uw-june!gordon ATT: (206) 527-0832 USnail: 5008 12th NE, Seattle, WA, 98105 Earth: 47 39' 55" N, 122 18' 46" W Reality?: An unimportant member of an unimportant species residing in an unimportant area of an unimportant planet circling an unimportant star partway out one arm of an unimportant galaxy in an Einsteinian, but otherwise unimportant universe.