Milton's "science"

[lucaspa]

This is an attempt to shorten the posts in the thread "Help on Shattering the Myths of Darwinism". This thread will focus on the "scientific" objections Milton and the Advocate raise.

 

Before I start addressing Milton, let's just do a reminder of the 5 different theories that Darwin proposed. These are:

 

"1. The nonconstancy of species (the basic theory of evolution)

2. The descent of all organisms from common ancestors (branching evolution).

3. The gradualness of evolution (no saltations, no discontinuities)

4. The multiplication of species (the origin of diversity)

5. Natural selection." Ernst Mayr, What Evolution IS. pg 86

 

Could part of the reason for this be that the core principle of natural selection cannot be studied in any experimental way. Milton claims that the celebrated principle of natural selection, formerly known as survival of the fittest, is in fact a tautology i.e. a statement of an inevitable (although previously unrecognised) relation.

 

This is one example of why I consider Milton a closet creationist. This is one of the standard creationist arguments against evolution. I find it in Henry Morris' 1974 Scientific Creationism. Milton is simply recycling it as tho it is valid.

 

First, let's look at that "natural selectio, formerly known as survival of the fittest". That's a misstatement of history. Darwin named the process "natural selection" in the first 3 editions of Origin. Then Herbert Spencer used the soundbite "survival of the fittest" and Darwin acknowledged it in the 6th edition of Origin. Like all soundbites of complex ideas, "survival of the fittest" does not represent the reality. So, let's do what we should do, critically examine the situation by going back and looking at the full description of natural selection:

 

"If, during the long course of ages and under varying conditions of life, organic beings vary at all in the several parts of their organization, and I think this cannot be disputed; if there be, owing to the high geometric powers of increase of each species, at some age, season, or year, a severe struggle for life, and this certainly cannot be disputed; then, considering the infinite complexity of the relations of all organic beings to each other and to their conditions of existence, causing an infinite diversity in structure, constitution, and habits, to be advantageous to them, I think it would be a most extraordinary fact if no variation ever had occurred useful to each beings welfare, in the same way as so many variations have occured useful to man. But if variations useful to any organic being do occur, assuredly individuals thus characterized will have the best chance of being preserved in the struggle for life; and from the strong principle of inheritance they will will tend to produce offspring similarly characterized. This principle of preservation, I have called, for the sake of brevity, Natural Selection." [Origin, p 127 6th ed.]

 

Now, look at this carefully. It is a deductive argument.

Premise #1: organisms vary.

Premise #2: there is a struggle for life, based on a geometric increase in numbers of individuals of a species combined with an arithmetic increase in resources.

Conclusion #1: Some variations will help the individual organism in the struggle for existence.

Conclusion #2: Such individuals, by inheritance, will produce offspring with the favorable variations.

 

If the premises are true, then the conclusions must be true. And Darwin spends 2 of the largest chapters in Origin demonstrating the truth of the premises.

 

It turns out that Darwinists are unable to specify any characteristic which would render an animal 'fit' or 'fittest' in advance. The old ideas of the fastest, strongest, most cunning, sexiest etc do not in any way predict the survival of an individual in a given experiment. It turn out that there is no accepted definition of 'fit' or 'fittest' other than the capacity of an organism to survive. Milton quotes George Simpson:

 

“To a geneticist, fitness has nothing to do with health, strength, good looks or anything but effectiveness in breeding.”

 

1. This inability to predict characteristics in advance is not totally true. What variation is "fit" depends on the environment. After all, a wing doesn't do a gopher any good. Environments are usually very complex and it is thus difficult to predict variations. But it has been done! Contrary to what Milton claims. This study did exactly that:

 

Evaluation of the rate of evolution in natural populations of guppies (Poecilia reticulata). Reznick, DN, Shaw, FH, Rodd, FH, and Shaw, RG. Science 275:1934-1937, 1997. The lay article is Predatory-free guppies take an evolutionary leap forward, pg 1880.

 

This is an excellent study of natural selection at work. Guppies are preyed upon by species that specialize in eating either the small, young guppies, or older, mature guppies. Eleven years ago the research team moved guppies from pools below some waterfalls that contained both types of predators to pools above the falls where only the predators that ate the small, young guppies live. Thus the selection pressure was changed. Eleven years later the guppies above the falls were larger, matured later, and had fewer young than the ones below the falls. The group then used standard quantitative morphology to quantify the rate of evolution.

 

So we have a study in the wild, not the lab, of natural selection and its results. In this study natural selection was measured quantitatvely, and even predicted since it was predicted that, in the absence of predators that fed on large guppies but in the presence of ones that fed on young guppies, the guppies would grow larger and mature earlier to avoid the predators. That is exactly what happened. Milton never mentioned this study, did he? Yet the book was published in 2001, nearly 4 years after the paper I cited.

 

2. Mendelian genetics gives us an objective means of measuring fitness. The mathematics of Mendelian genetics leads to the Hardy-Weinberg principle which, briefly stated, says that in the absence of outside influence, the allele frequency in a population stays constant. So fitness is the ratio of the progeny actually produced to the progeny expected from Mendelian inheritance. Fitness is therefore always relative (Understanding Evolution, pp. 153-154.) We can also get a selection coefficient that measures the selective advantage, or disadvantage. S = 1.0 - fitness.

 

Now, to get into greater detail, there are some things that can perturb a Hardy-Weinberg equilibrium. A very small population will do so, in which case genetic drift comes into play as significant. Gene flow from other populations will also cause a shift in allele frequency, as will non-random mating. So all these have to be eliminated before a conclusion of natural selection can be made. However, those factors are eliminated in hundreds of studies in the field of population genetics. The Grant study of the beaks of the Galapagos finches did so.

 

“Darwinists are now reluctant to try and explain any particular characteristic as being responsible for the giraffes evolution – even regarding its long neck – because they would have to show how and why that characteristic has favoured the Giraffe over other animals, some of which are extinct."

 

Not true. The evolution of the long neck is explained by lengthening of the individual vertebrae. And the reason is simple: being able to get to a food source no other mammal in that ecosystem can reach. Also Milton is mistaking evolution here. He refers to "favoured the Giraffe over other animals". That isn't how natural selection works. Natural selection works in favoring individuals over other individuals in the same species. The competition is not against other species primarily, but against members of your own species.

 

The problem of the failure to find transitional forms has bedevilled Darwinism since it was first proposed and until recently was all but swept under the carpet. For over 100 years, the question of the complete absence of transitional species was justified on the basis that the probability of an intact fossil surviving must be vanishingly small.

 

This is another recycled creationist argument. Duane Gish's book Evolution? The Fossils Say NO! from 1979 is based on this. Note the claim "complete absence" and "transitional species". It is false. There are 3 types of transitional fossils:

 

1. Transitional individuals. These are individual organisms that connect one species to another. Some fossil records are so complete that transitional individuals can be traced from species to species to new genera, family, order, and even class! I've posted a partial list of references that have such sequences elsewhere on the web: http://www.christianforums.com/t43227 I can recreate it here if you wish. And yes, I went and looked up the references.

 

2. Successive species. These are fossils of species connecting "higher" taxa. The horse lineage is mostly transitional species (altho there are instances of transitional individuals within it). The transition from amphibian to mammals thru the Therapsids is an example of transitional species. Many times individual paleontologists have transitional individuals but report successive species.

1. http://www.gcssepm.org/special/cuffey_04.htm

2. http://www.origins.tv/darwin/transitionals.htm

3. http://www.asa3.org/ASA/resources/Miller.html

4. Transitional fossils: http://asa.calvin.edu/ASA/resources/Miller.html

5. Horse evolution: http://chem.tufts.edu/science/evolution/HorseEvolution.htm

 

3. Successive higher taxa

 

4. Isolated intermediates. Archeopteryx was, for a long time, an isolated intermediate between reptiles and birds.

 

I found many of these types of transitionals documented in an article by RJ Cuffey in his chapter in Science and Creationism published in 1984. How could Milton miss this?

 

So the transitionals in the fossil record are there. Despite Milton's claims to the contrary. So why Punctuated Equilibrium?

 

What about Darwins original prediction of the eventual recovery of many examples of gradual evolution in the fossil record. “for one thing, Darwin mused, paleontology in his day was still in its infancy. Surely he wrote, paleontology would eventually provide full corroboration of his theory. “Darwin actually believed that his entire theory of “transmutation” (or descent with modification -he never called it “evolution” in the Origin) would stand or fall on the eventual recovery of many examples of gradual evolution in the fossil record.” - Niles Eldredge (emphasis mine)

 

It would be nice if you would give the WHOLE SOURCE, not just that it is "Niles Eldredge". We also need to check to see if Milton is quoting out of context.

 

However, Eldredge is quoting what "Darwin ... believed". That is different from what is actually necessary. Now, as I've shown above, there are "many examples of gradual evolution in the fossil record." But Darwin mostly argued for something called "phyletic gradualism" as the major mechanism of #2 and #4 theories above. Phyletic gradualism is the transformation of one large population (species) to another species over the course of generations. It is also called "anagenesis". You start with one species and you end with one species. If ALL speciation were by this method, of course, soon we would be out of species. After all, species go extinct. So gradually you would lose species until there were none left. Phyletic gradualism would leave many more transitional series in the fossil record than what we see.

 

So, what does Milton say?

Milton states that :

 

“Steven J Gould and Niles Eldrige of Harvard have proposed a theory of 'punctuated equilibrium', in order to account for the lack of fossil remains of transitional species. They have suggested that evolution is not a constantly occurring phenomenon; that species may have remained stable for long periods of geological history leaving many fossil remains, and that the periods of evolutionary change, when they came, did not last very long. This would account for the lack of transitional fossils.” (emphasis mine)

 

Now, before we get to PE, let's look at Darwin:

"Many species once formed never undergo any further change ... and the periods, during which species have undergone modification, though long as measured by years, have probably been short in comparison with the periods during which they retain the same form." Charles Darwin, Origin of Species, 4th and later editions, pg. 727

 

So Darwin wasn't totally committed to phyletic gradualism. His theory was dependent on it.

 

Another way to have speciation is cladogenesis. In this view a population splits into 2 or more species. You start with 1 species and end up with 2 or more. The most famous form of cladogenesis is allopatric speciation. In allopatric speciation, a small population gets geographically isolated from the large main population: across a river, over mountains, rise of the Isthmus of Panama, etc. The small population faces a different environment and transforms under natural selection to a new species. It can then migrate back into the range of the larger population and thus "suddenly" appear at that location.

 

"The modern theory of evolution does not require gradual change. In fact, the operation of Darwinian processes should yield exactly what we see in the fossil record. It is gradualism that we must reject, not Darwinism. ... Evolution proceeds in two major modes. In the first, phyletic transformation, an entire population changes from one state to another. If all evolutionary change occurred in this mode, life would not persist for long. Phyletic evolution yields no increase in diversity, only a transformation of one thing into another. Since extinction (by extirpation, not by evolution into something else) is so common, a biota with no mechanism for increasing diversity would soon be wiped out. The second mode, speciation, replenishes the earth. New species branch off from a persisting parental stock.

"Darwin, to be sure, acknowledged and discussed the process of speciation. But he cast his discussion of evolutionary change almost totally in the mold of phyletic transformation. ...

"Eldredge and I believe that speciation is responsible for almost all evolutionary change. Moreover, the way in which it occurs virtually guarantees that sudden appearance and stasis shall dominate the fossil record.

"All major theories of speciation maintain that splitting takes place rapidly in very small populations. The theory of geographic, or allopatric, speciation is preferred by most evolutionists for most situations (allopatric means 'in another place'). A new species can arise when a small segment of the ancestral population is isolated at the periphery of the ancestral range. Large, stable central populations exert a strong homogenizing influence. New and favorable mutations are diluted by the sheer bulk of the population through which they must spread. They may build slowly in frequency, but changing environments usually cancel their selective value long before they reach fixation. Thus, phyletic transformation in large populations should be very rare - as the fossil record proclaims.

"But small, peripherally isolated groups are cut off from their parental stock. They live as tiny populations in geographic corners of the ancestral range. Selective pressures are usually intense because peripheries mark the edge of ecological tolerance for ancestral forms. Favorable variations spread quickly. Small, peripheral isolates are a laboratory of evolutionary change.

"What should the fossil record include if most evolution occurs by speciation in peripheral isolates? Species should be static through their range because our fossils are the remains of large central populations. In any local area inhabited by ancestors, a descendent species should appear suddenly by migration from the peripheral region in which it evolved. In the peripheral region itself, we might find direct evidence of speciation, but such good fortune would be rare indeed because the event occurs so rapidly in such a small population. Thus, the fossil record is a faithful rendering of what evolutionary theory predicts, not a pitiful vestige of a once bountiful tale.

"Eldredge and I refer to this scheme as the model of punctuated equilibria." SJ Gould, The episodic nature of evolutionary change. In The Panda's Thumb, 1980, pp.179-185.

 

Thus Milton misstated PE!

 

“The difficulty with punctuated equilibria is that it is wholly speculative and has been introduced simply to account for the lack of fossils that ought to exist in the neo-Darwinist theory.”

 

Sorry, but again Milton is missing the literature. PE has been documented in the fossil record:

1. Williamson, PG, Paleontological documentation of speciation in cenozoic molluscs from Turkana basin. Nature 293:437-443, 1981. Excellent study of "gradual" evolution is an extremely fine fossil record.

2. A trilobite odyssey. Niles Eldredge and Michelle J. Eldredge. Natural History 81:53-59, 1972. A discussion of "gradual" evolution of trilobites in one small area and then migration and replacement over a wide area. Is lay discussion of punctuated equilibria, and does not overthrow Darwinian gradual change of form. Describes transitionals.

 

Again, notice the dates. Looong before Milton wrote. So why is Milton writing statements that have already been refuted before Milton wrote them? Is Milton simply incompetent? Or does he have a secret agenda?

 

It is very clear to myself as an outsider that accepting Darwinism is no longer about accepting an elegant and simple theory backed up conclusively by evidence. Instead I am being asked to accept core hypotheses which cannot be proven along with hundreds of auxiliary hypotheses.

 

1. Darwinism is conclusively backed by evidence. Milton is wrong in his assertions.

2. You do the same thing in physics. The Standard Model of particle physics is also core hypotheses with hundreds of auxiliary hypotheses. So is quantum mechanics and relativity. So why does this not present a problem for you in physics but does in biology?

 

Just now I want to see if clear cut evidence can be produced which conclusively supports some historical adaption, any adaption; such as the Giraffes neck, the fiddler crabs big claw, etc. I want to know whether or not you consider these stories scientific and verifiable or not. I dont want speculation. Are they currently part of the Darwinian explanatory repertoire or have they been dropped as Milton claims?

 

Let's start with the last sentence. I made clear that the example of the giraffe's neck was never intended as solid evidence about evolution. It was intended simply as a means of illustrating the differences between Lamarckism and Darwinism.

 

Now, is there evidence supporting historical adaptation? Yes. Much of it comes from looking at living species that have intermediate features. For instance, the entire taxonomic family that contains skinks are intermediate between legged reptiles and snakes. Within that family you can find every intermediate between legs like lizards and legless like snakes. Here is one of the intermediates: http://www.kingsnake.com/oz/lizards/skinks/ldeserto.htm

 

Another example of evolution of adaptation in living species is the evolution of the placenta. The intermediates are in a living genera of fish:

1. David N. Reznick, Mariana Mateos, and Mark S. Springer Independent Origins and Rapid Evolution of the Placenta in the Fish Genus Poeciliopsis Science 298: 1018-1020, Nov. 1, 2002. Intermediate steps in same genus. http://www.u.arizona.edu/~mmateos/reznicketal.pdf News article at: http://www.sciencemag.org/cgi/content/full/298/5595/945a

 

The evolution of wings -- both insect and bird -- has also been studied. These are examples of "exaptation". This is when a trait evolves for one reason and then at some point acquires another function. In the interest of space, let's just do insect wings.

 

Insect wings are modified gills. Because they have lots of vasculature, gills out of water make very good heat exhangers:

5. Averof, M and Cohen, SM, Evolutionary origin of insect wings from ancestral gills. Nature, 385: 627-630, Feb. 13, 1997.

 

So now you have heat exchangers. It turns out that the bigger the modified gill, the better it is at being a thermoregulator.

JG Kingsolver and MAR Koehl Aerodynamics, thermoregulation, and the evolution of insect wings: differential scaling and evolutionary change, Evolution, 1985.

 

First, Kingsolver and Koehl examined the 3 categories of functional continuity: proto wings for gliding, for parachuting, and attitude stability. They then developed aerodynamic equations for exactly how proto-wings should help an insect under these 3 hypotheses. They then went on to construct insect models of flying and nonflying forms among early fossil insects. To these models they attached wings of various lengths and measured the actual aerodynamic effects for properties predicted by various hypotheses of functional continuity. The results of wind-tunnel tests were consistent: aerodynamic benefits of begin for wings above a certain size, and they increase as wings get larger. But at small sizes of insect proto-wings, aerodynamic advantages are absent or insignificant. Kingsolver and Koehl then tested their models for thermoregulatory effects. They achieved results symmetrically opposite to aerodynamic benefits: for thermoregulation, wings work well at the smallest sizes, with benefits increasing as the wing grows. however, beyond a measured length, further increase in wing size confers no additional thermo effect. These 2 effects can be graphed.

 

Interestingly enough, the size at which wings begin to lose any additional benefit to thermoregulation is the size at which aerodynamic effects begin to kick in. So, by actual measuring the functional shift, Kingsolver and Koehl have shown that incipient wings aid thermoregulation but provide no aerodynamic benefit -- while larger wings provide no further theromoregulatory benefit but initiate aerodynamic advantage and increase the benefits steadily thereafter. Cool, huh? Wings evolve as thermoregulators and, at a particular size, are good for flying. And all this is quantitatively studied in insect models.

 

Does this qualify as "solid evidence" for an historical adaptation? I would say that it is in the same league with the evidence for heliocentrism: no reasonable person could deny it.