Weekend Humor #3
I linked to this post a long time ago, but that was when I was the only one reading my blog. I think this is still my favorite Scrappleface post on the evolution debates. It begins:
Elderly residents still recall stories of the dust clouds that rolled through Salina as herds of Darwinists thundered across the Kansas plains unchallenged by competition -- unquestionably dominating, and some say destroying, their environment.But as selective pressures mounted, Darwinists forced to fend for themselves in the natural arena of logic
often fell prey to scrappy skeptics who contended
Some celebrate the success of the skeptics as healthy for the overall environment, while concerned conservationists race against the clock to raise funds and public awareness to rescue and shelter the Darwinist.
As they were driven from the public square in recent decades, Darwinists sought shelter in classrooms where they received protection from competing species and intellectual predators.
posted by Lawrence Selden @ 4:14 PM
4 comments
4 Comments:
Alexandra it's painfully obvious from your two posts that you are unfamiliar with the scientific use of the term "theory" and the actual nature of irreducible complexity. You've swallowed Christian pop culture tracts from ideologues like Michael Behe hook, line and sinker, and have not put them to the test of scrutiny that your human brain can afford.
If you knew about the differentiation between evolution and natural selection, you would know that the former is a scientific fact and the latter is the method by which the former operates, and is the thing that is continually qualified and reclarified. You would also recognize that Michael Behe conflates objections to natural selection into objections to evolution.
But you've read a handful of texts by authors with a religious agenda, and now you have a completely distorted view of what evolution by natural selection is, and what it isn't. Hopefully a college level bio couse will straighten this out.
alexandra
I literally let out a gasp when I read what you just wrote. Despite that, I think I have a really interesting and educational post for you - I hope you read all of it. But I do have one paragraph of caveats:
By introducing the pejorative term "tautology" you've demarcated your inquiry as a completely loaded question, and now I have to clean up the mess. Imagine if I said "your pleonasm is appreciated." Also, a phrase like "clarify your tautology" is not really a common use of term, and sounds distantly familiar from some ID tome by Behe or someone, but unforuntately I can't remember or pinpoint its origin right now. It suffices to say that you're repeating bilge that you've read by authors with a strictly religious agenda, and it sounds from the terse phrasing of your request that you're carfully wading through unfamiliar waters. That makes sense, if all you've read about the subject is from sophists like Behe and Dembski. I suggest that you approach with an open and inquisitive mind a bio major or professor with such questions.
Alright, I'll explain the notion of evolution and natural selection separately. For further reading, Ernst Mayr, author of the 2001 book "What Evolution Is" was an excellent expositor of all this.
The term "evolution" refers to the fact that organisms and forms change over time and evolved from a common ancestor. That is where it ends. It does not pose how they change, and it does not name the mechanism which would allow or force them to change. "Evolution" only refers to the fact that things change. It does not say whether or not things evolve gradually or in fits and spurts, just that they do.
The terms "theory" and "law" are inapplicable to the term "evolution" as it is not a regular, consistent, predictable force, just a thing that happens. It's just a fact, and we know it happens by the evidence of living things from microbes to large animals to diseases evolving.
The phrase "the theory of evolution" is used as shorthand to say "the theory of evolution by natural selection." It's just easier to say "the theory of evolution" but, as I said before, "evolution" itself is not a theory, and it's not a law. It's just a thing that happens.
Before I get in to the theory of natural selection, you need to be educated about the scientific term "theory." The following is a surprisingly excellent definition of the terms from http://wilstar.com/theories.htm (but you can check them from many, many other sources online):
Scientific Law: This is a statement of fact meant to explain, in concise terms, an action or set of actions. It is generally accepted to be true and univseral, and can sometimes be expressed in terms of a single mathematical equation. Scientific laws are similar to mathematical postulates. They don’t really need any complex external proofs; they are accepted at face value based upon the fact that they have always been observed to be true.
Some scientific laws, or laws of nature, include the law of gravity, the law of thermodynamics, and Hook’s law of elasticity.
Hypothesis: This is an educated guess based upon observation. It is a rational explanation of a single event or phenomenon based upon what is observed, but which has not been proved. Most hypotheses can be supported or refuted by experimentation or continued observation.
Theory: A theory is more like a scientific law than a hypothesis. A theory is an explanation of a set of related observations or events based upon proven hypotheses and verified multiple times by detached groups of researchers. One scientist cannot create a theory; he can only create a hypothesis.
In general, both a scientific theory and a scientific law are accepted to be true by the scientific community as a whole. Both are used to make predictions of events. Both are used to advance technology.
The biggest difference between a law and a theory is that a theory is much more complex and dynamic. A law governs a single action, whereas a theory explains a whole series of related phenomena.
An analogy can be made using a slingshot and an automobile.
A scientific law is like a slingshot. A slingshot has but one moving part--the rubber band. If you put a rock in it and draw it back, the rock will fly out at a predictable speed, depending upon the distance the band is drawn back.
An automobile has many moving parts, all working in unison to perform the chore of transporting someone from one point to another point. An automobile is a complex piece of machinery. Sometimes, improvements are made to one or more component parts. A new set of spark plugs that are composed of a better alloy that can withstand heat better, for example, might replace the existing set. But the function of the automobile as a whole remains unchanged.
A theory is like the automobile. Components of it can be changed or improved upon, without changing the overall truth of the theory as a whole.
Some scientific theories include the theory of evolution, the theory of relativity, and the quantum theory. All of these theories are well documented and proved beyond reasonable doubt. Yet scientists continue to tinker with the component hypotheses of each theory in an attempt to make them more elegant and concise, or to make them more all-encompassing. Theories can be tweaked, but they are seldom, if ever, entirely replaced.
I apologize for the quote's length, but it's necessary to understand all of that. It's interesting to note, as well, that the quote came from a self-described "Christian" and "family-friendly" website. Note also that they use the shorthand "theory of evolution."
Right. Anyway, the "natural selection" qualification on "evolution" is what is the theory. It's a complicated idea that actually has its origins in the writings of Thomas Malthus, an 18th-19th century political philosopher. In 1798, Malthus predicted population would outrun food supply, leading to a decrease in food per person. This prediction was based on the idea that population if unchecked increases at a exponential rate - e.g. 2, 4, 8, 16, 32, 64, 128, etc. - whereas the food supply grows at an arithmetic rate - e.g. 1, 2, 3, 4, 5, 6, 7, etc. He thought it would lead to a population/demographic catastrophe since population would outgrow resources, and people would necessarily die en masse. Obviously, this did not happen, thanks to technological advances, the expansion of the market economy, division of labor, and stock of capital goods.
How Malthus relates to natural selection, though, is that until he came along, most considered all resources to be unlimited, or at least growing at a rate commensurate with population growth, so in effect, inexhaustible. Charles Darwin (along with several contemporaries of his) picked up on Malthus, and took away from him basically that resources are not unlimited, and they actually could control population growth in a natural environment.
So, given that not every organism born will survive to maturity (because resources are finite), organisms which do survive to reproductive maturity must have a reproductive/survival advantage over those that don't - or conversely, that those who don't last long enough to reproduce had something going against them that their relatives (immediate or distant) didn't. But what was that thing they had going against them?
Darwin had observed from his famous Galapagos finches and other species that similar organisms in different locations had looked different. Most saliently in the shapes of their beaks. Some are long, some are short and stumpy, some are curved, etc. The curved ones all lived together, and the short ones all lived together, and so on, and they were all scattered about the islands, but the islands are all relatively close together. He put together, over a course of years, that these differentiations could be explained by the environment surrounding them. But how?
How could these beaks "know" to grow in to different shapes to suit their envionments? Maybe shoving them in to different shaped holes was warping them? No. It doesn't work like that.
For the finches, their evolution was all about diet. The islands' environments are all different, with a heterogenous variety of plants, animals and insects, all of which different finches were seen feeding on. On various islands, finch species have become adapted for different diets: seeds, insects, flowers, the blood of seabirds, and leaves. For example, If there were many cactuses on an island, but relatively few instects, the finches born with beaks well-suited for drawing nourishment out of cactuses would fare better than finches born with beaks which were better-suited to catching insects. The more successful varieties would feed better, and more would survive to sexual maturity, and consequently would reproduce in greater numbers than the varieties that were ill-suited to their surroundings, and thus their traits would become predominant in subsequent generations.
But why did the beaks differ at all in the first place? The answer lies in random mutation. When cells divide and genes replicate, or other biological reproductive processes take place, the replications are not always identical copies of their parent cells, genes, bodies or what have you. These variances are called mutations, and do not happen with any regular, predictable certainty. Genetic variance accounted for the variety of beaks, in finches, and accounts for the variety of life in general.
Now, this process of natural selection, again, is what is the theory. As you can see, it entails many different processes, and there are many different fine points and specifics involved which could all explain how it happens. But these differences do not disprove that it does happen, just that there are still questions as to what processes are employed at what points and to what degrees that lead to its happening. And natural selection is where all the new ground is being explored. There are many new ideas coming in on mutation, and gene flows, and all sorts of other things, so it's very exciting. Since the field is still being voraciously explored, however, there are necessarily going to be differing hypotheses on how various specifics work (with most of these specifics, a PhD is required just to understand what the question is about).
So that, in a nutshell, is a generalization of how evolution works, and how natural selection works. Evolution is just a fact of life that occurs every day, and the theory of natural selection is there to provide a mechanism by which evolution can occur. We know for certain that evolution happens, and we're really, really sure that it happens through natural selection, and we're still exploring just how exactly natural selection takes its course on the smallest and most specific levels.
I hope that this explains your short question, but I'll be happy to elaborate on any of these points if you'd like.
Please don't let Behe's talking points do your thinking for you...
http://www.nature.com/nature/journal/v415/n6874/full/nature716.html
And your equation is still wrong:
(Mutations+NS)time=Evolution by Natural Selection. It does not equal simply "Evolution." "Evolution" != "Evolution by Natural Selection," "Evolution"="Evolution."
stewie;
You idiot, you got it backwards. Natural selection is a fact that has been documented for 5000 years. Evolution is not a fact. Evolution is not even a theory. It cannot be falsified. Evolution is a "piss poor postulate" that has almost no science behind it.
We have documented billions of trillions of species reproducing their own species. We have no, none, nada examples of ANY species changing into another species.
With billions of trillions of the same scientific fact verses zero evidence of change of species only morons could believe in evolution.
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