James Q. Wilson explains it as clearly as is possible:
The other meaning of theory is the popular and not the scientific one. People use “theory” when they mean a guess, a faith or an idea. A theory in this sense does not state a testable relationship between two or more things. It is a belief that may be true, but its truth cannot be tested by scientific inquiry. One such theory is that God exists and intervenes in human life in ways that affect the outcome of human life. God may well exist, and He may well help people overcome problems or even (if we believe certain athletes) determine the outcome of a game. But that theory cannot be tested. There is no way anyone has found that we can prove empirically that God exists or that His action has affected some human life. If such a test could be found, the scientist who executed it would overnight become a hero.
Evolution is a theory in the scientific sense. It has been tested repeatedly by examining the remains of now-extinct creatures to see how one species has emerged to replace another. Even today we can see some kinds of evolution at work, as when scholars watch how birds on the Galapagos Islands adapt their beak size from generation to generation to the food supplies they encounter.
***Proponents of intelligent design respond by saying that there are some things in the natural world that are so complex that they could not have been created by “accident.” They often use the mousetrap as a simile. We can have all of the parts of a trap–a board, a spring, a clamp–but it will not be a mousetrap unless someone assembles it. The assembler is the “intelligent designer.”
***What schools should do is teach evolution emphasizing both its successes and its still unexplained limitations. Evolution, like almost every scientific theory, has some problems. But they are not the kinds of problems that can be solved by assuming that an intelligent designer (whom ID advocates will tell you privately is God) created life. There is not a shred of evidence to support this theory, one that has been around since the critics of Darwin began writing in the 19th century.
Some people worry that if evolution is a useful (and, so far, correct) theory, we should still see it at work all around us. We don’t. But we can see it if we take a long enough time frame. Mankind has been on this earth for about 100,000 years. In that time there have been changes in how people appear, but they have occurred very slowly. After all, 1,000 centuries is just a blink in geological time.
Of course, those observations are pointless when dealing with the ‘young earth’ crowd, and all ID proponents are doing is providing creationists with cover. Thank goodness, people are beginning to see through it.
As a side note, did any of you have to read James Q. Wilson’s texts as an undergrad?
Zifnab
Um… no. Evolution, and evolutionary models are very key and very fundamental to a number of different wide-ranging fields. Probably my favorite field in which evolution has played a crucial role is in computer software architecture. The “genetic algorithm” along with a number of other very successful and widely used computer proceeders hinge strongly on the concept of success by trial and error and evolution of a data structure.
Just check out http://www.pandora.com to see an example of evolution at work in the modern world. Admittedly, it’s not an organic system, but such algorithms can be used to debunk the mousetrap paradox and the irreducibly complex system.
Zach Wendling
Not in undergrad, but the textbook he wrote with John DiIulio was my high school government textbook, and I remember it quite fondly as being excellent.
Mike Quinlivan
Yep, I had a couple of his books for college. I believe they were “Crime and Human Nature” and “Fixing Broken Windows”. Maybe the second was not his; I can’t remember at the moment.
Jack Roy
Yup. Although Mr. Wilson definitely seemed to be retained reluctantly, and gradually replaced with more… modern viewpoints. I think the tendency is unfortunate, but no one even reads V.O. Key anymore in poli sci classes.
And Zifnab, I’m a devout Darwinist, but Pandora makes me suspect divine intervention. That site is teh roxxorz.
BrianOfAtlanta
But can evolutionary models explain Coelacanths, which don’t seem to be very well adapted to their current environment, yet refuse to evolve?
Evolutionary models are one thing. Evolutionary reality is another. I’ll side with Mr. Wilson in saying that evolution is a useful theory, but how it should work and how it does work are still two very separate things.
capelza
Sincerely just asking here, but on what information do you base your statement that coelacanths are poorly adapted to their conditions?
Neo
The truth is out there.
Ba'al
Capelza’s remark about coelacanths is to the point. They live quite deep (usually), mostly in caves adjacent to undersea volcanoes. The details of their habitat are not well known, so it is impossible to say that they are not well adapted to their environment. One can say that it is unlikely to be an environment with a large number of species. The fact that they have found such a remote niche could well explain their survival. Their behavior has only been observed once (in a submersible). They appear to be opportunistic bottom feeders, and they have an electroreceptor in their tail that they may use to detect prey species. Interestingly, they were not observed to use their “legs” for walking.
We can still find lampreys too (which are an even older distinct lineage). We still find lots of them (at least 200 species) because they are sufficiently good at what they do to continue to survive long enough to reproduce.
A common misconception is that evolution always leads to greater and greater complexity (sometimes the opposite occurs) or that it is a single line leading ultimately to us (nope) or that natural selection is the only force at work (nope, there is sexual selection and various forms of isolation coupled with genetic drift).
There are way too many people making comments about this who have no clue what they are talking about. Mostly wingnuts.
Ba'al
For those who worry if evolution is “useful”, or if “it is at work around them”, then I say that if you die of an opportunistic infection in a hospital that is resistant to all of the known antibiotics, then you will see evolution in action.
By the way, the CDC in Atlanta works closely with outstanding evolutionary biologists (several at neighboring Emory University) to understand this very thing, as well as the population dynamics that underlie spread of infections.
demimondian
Indeed. Coelacanths are almost a stereotypical example of a evolution in action: they’re not competitive against modern bony fish, but they can survive in an environment where bony fish cannot, and so they have retreated to that environment. They may not be terribly well-adapted to the benthic conditions in which they seem to live — but they are better adapted than anything else, and, therefore, they survive.
That’s survival of the fittest in a nutshell: you don’t have to be terribly fit to be the fittest; you just need to be better than the competition. (“Why are you tightening your sneakers? You can’t outrun a bear!” “You’re right. Fortunately for me, I just need to outrun *you*”)