Friday, December 20, 2002

Robert Wright, Call Your Office

An update of sorts on a past blog post. Evidence that the male perception of feminine beauty is changing as reported by the British Medical Journal:
The assertion comes from two psychoanalysts who pored over every Playboy from December 1953 and calculated the body mass index of every centrefold. Over 577 issues, the models became taller and their waist increased, while their hips became narrower and their bust became smaller. If Playboy is any guide, the needle on the male sexual compass has switched from Marilyn Monroe to Eva Herzigova, the scientists say.

The body of evidence is a slap to evolutionary biologists who contend that men have always preferred women with big curves because of the association of breasts and hips with health and fertility.
Not to worry. I'm sure that a theory that so obviously explains everything will have no problem incorporating this.

Thursday, December 19, 2002

What is Evolution? (again)

Doing some research on the conventional thinking on human origins, I happened across the Becoming Human web site. I noticed that this traditional darwinian-oriented site included a glossary of terms. I checked their definition of Evolution:
A change in a population over time. Genetically, this means a change in the frequency of certain alleles over many generations.
An allele is the alternate form of a gene or trait. For example, A, B, and O are the possible alleles of the gene for human bloodtype. If this is evolution, I can't think of anyone who would question it.

Friday, December 13, 2002

The Cliffs of Mount Improbable

Richard Dawkins has written four or five books with the same basic theme: Darwinism only looks impossible. If you break it down into small plausible steps, then seemingly complex systems can be built up one tiny piece at a time. In Dawkins words, from the title of one of his books, darwinism “climbs Mount Improbable” by taking the back way up the gentle slopes. The problem is that these gentle slopes don’t really exist. Darel Rex Finley makes this point nicely and gives a name to the real topography: the Benefit Cliff. I can’t do graphics here, so be sure to take a look at Darel’s essay for a more thorough discussion of this point.
On paper, evolution assumes that the beneficial function of a complex system can be slowly accumulated, as the parts of the system are accumulated. This concept is vital, because for complex systems to arise by the guidance of natural selection, the accumulating parts of the system must provide a benefit which natural selection can select.

Empirical studies of biology show that all life forms, from the simplest microbes to humans, are filled with complex systems that do not appear to be amenable to this evolutionary requirement. Instead of a smooth path from nonexistence to the modern state, most biological systems exhibit what might be described as a "benefit cliff," impassable by chance mutation.

To illustrate — consider the car. There are many parts on the car which are beneficial, but not strictly necessary. It is safer to drive with a rear-view mirror, but we could still drive without one. It is comfortable and fun to have air conditioning and a stereo, but we could still drive from one city to another without those things.

Suppose we remove all of these frills, stripping the car down to only what is absolutely necessary to drive from point A to point B, at a level of utility greater than could be provided by a bicycle. The car would still be very complex. A large number of critical parts (particularly in the engine) could not be removed.

The obvious problem is that natural selection doesn't even get to start selecting until a rather large amount of complex functionality is achieved. But if natural selection didn't design the complexity, then what did?

Most evolutionists today are aware of this problem, but insist that the incremental path required by evolution… does exist; it just "hasn't been discovered yet." Of course, any false theory could be defended this way: "It only looks false; its truth hasn't been discovered yet."

It is conceivable that a beneficially-neutral part could arrive, and stick around until — by unbelievably spectacular chance — other parts arrived that would work together with that one. But then we should expect to see most life forms rife with unused parts that may one day be beneficial in combination with as-yet-nonexistent parts. We do not observe anything of the sort. Useless or apparently useless features, such as the human appendix, are very unusual exceptions, not the general rule.
I have tried, on various evolution discussion boards, to get an explanation on how a complex system could evolve under the Dawkins scenario. The quality of the responses, from some highly educated people, is basically on the level of a four-year-old describing how a computer works: “the electricity goes in here, it does something in this box, and that makes pictures on this screen.” Usually these discussions end with something like “we may not understand all the details of the mechanism but that does not invalidate the fact of evolution.” Yes, and this used car I’m selling you, even though I can’t seem to find an engine, is still a totally viable means of transportation.

Sunday, December 01, 2002

What is Evolution?

I was asked, in response to one of my posts, where exactly I stood and to what, about ‘evolution’, did I object. That’s a fair question, but not an easy one since an answer requires first a clear idea of what is evolution. Talkorigins.org is one of the most influential promoters of evolutionary theory on the world wide web. Their site contains a collection of essays intended to provide a solid background in evolution for anyone who wishes to enter the various debates on the subject. Consider carefully these definitions from a Talkorigins essay entitled What is Evolution?
"evolution: The gradual process by which the present diversity of plant and animal life arose from the earliest and most primitive organisms, which is believed to have been continuing for the past 3000 million years." – Oxford Concise Science Dictionary

"evolution: ...the doctrine according to which higher forms of life have gradually arisen out of lower.." – Chambers Dictionary

"evolution: ...the development of a species, organism, or organ from its original or primitive state to its present or specialized state; phylogeny or ontogeny" - Webster's Dictionary
If you maintain a belief in evolution and if any of these definitions sound about right to you, then I am sorry to inform you that you are scientifically illiterate. That is not my assessment, but that of the essay’s author, Talkorigins contributor and scientist Laurence Moran, who says of the first statement: “This is not a scientific definition…inexcusable for a dictionary of science” while the other two are “simply wrong.” Please note that these statements have not been edited in any way by me as you can see here. Personally, I’ve never had a discussion about evolution with anyone who I think would seriously question the basic premises any of those definitions.

On the other hand, Moran quotes approvingly:
“Evolution is a process that results in heritable changes in a population spread over many generations.”

This is a good working scientific definition of evolution; one that can be used to distinguish between evolution and similar changes that are not evolution. Another common short definition of evolution can be found in many textbooks:

"In fact, evolution can be precisely defined as any change in the frequency of alleles within a gene pool from one generation to the next." - Helena Curtis and N. Sue Barnes, Biology, 5th ed. 1989 Worth Publishers, p.974
Based on these definitions, I would be a true believer in evolution. If you release a population of brown mice on a snow covered plain with an adequate food supply, little cover, and the occasional hungry hawk lurking overheard, I have no trouble with the idea that over time, either by recombination of recessive genes or an albino mutation, the population could turn from brown to white.

As usually happens, though, once we have the simple, clear, and innocuous concept of evolution in place, we move on to the shifting sands of darwinian speculation. Moran quotes how “one of the most respected evolutionary biologists has defined biological evolution:”
"In the broadest sense, evolution is merely change, and so is all-pervasive; galaxies, languages, and political systems all evolve. Biological evolution ... is change in the properties of populations of organisms that transcend the lifetime of a single individual. The ontogeny of an individual is not considered evolution; individual organisms do not evolve. The changes in populations that are considered evolutionary are those that are inheritable via the genetic material from one generation to the next. Biological evolution may be slight or substantial; it embraces everything from slight changes in the proportion of different alleles within a population (such as those determining blood types) to the successive alterations that led from the earliest protoorganism to snails, bees, giraffes, and dandelions."
- Douglas J. Futuyma in Evolutionary Biology, Sinauer Associates 1986
Most of this statement is more of what we see above; simple and straightforward. But the author finishes up in full darwinist mode: The process by which a population can become predominantly blue-eyed instead of green-eyed can account for the journey from protoorganism (I assume he means whatever is supposed to have preceded the first single cell organism) to the giraffe.

Moran journeys back to safer ground for his conclusion:
Recently I read a statement from a creationist who claimed that scientists are being dishonest when they talk about evolution. This person believed that evolution was being misrepresented to the public. The real problem is that the public, and creationists, do not understand what evolution is all about. This person's definition of evolution was very different from the common scientific definition and as a consequence he was unable to understand what evolutionary biology really meant. This is the same person who claimed that one could not "believe" in evolution and still be religious! But once we realize that evolution is simply "a process that results in heritable changes in a population spread over many generations" it seems a little silly to pretend that this excludes religion!

Scientists such as myself must share the blame for the lack of public understanding of science. We need to work harder to convey the correct information. Sometimes we don't succeed very well but that does not mean that we are dishonest. On the other hand, the general public, and creationists in particular, need to also work a little harder in order to understand science. Reading a textbook would help.
This reminds me a little of the fate of the Democratic Party in this last election cycle, blaming it on the failure to get their “message” out. The quality of the message does not seem to be a consideration. Well, I’ve read a few textbooks and I know a little about science, but I still don’t know what exactly ‘evolution’ means. I’m afraid that Dr. Moran’s essay has not really helped unless I’m free to pick the definition I like. If so, I’d take “a process that results in heritable changes in a population spread over many generations.” But protoorganisms to giraffes? Those two definitions can only be connected, at least for the non-scientist, by taking the most superficial view of the whole enterprise and/or stupendous leaps of faith and suspensions of common sense.