Evolution is a basic, biological process

Boy, all this confusion just because of definitions.Strictly speaking, a law is just a theory. Some theories we call theories, some we call laws. There are no formal rules of nomenclature regarding whether a theory is referred to as a theory or as a law, but in general, the more mathematically and precisely a theory can be expressed, the more likely it will be referred to as a law.But this is not a hard and fast rule. We still refer to Newton's Laws, even though they were shown inaccurate for velocities above a significant fraction of c (speed of light) by Einstein's theory of relativity. Imagine that, a law superceded by a mere theory. Of course, it's incorrect to characterize it this way. We call them Newton's Laws because we've always called them Newton's Laws, and we're not going to stop calling them Newton's Laws just because they were found lacking under some circumstances.Because laws are just theories that we happen to call laws, there are no special rules regarding them. One cannot claim that theories can be challenged and laws cannot. Whether we call them laws or theories, they're both just tentative frameworks of understanding built upon a body of data. Conflicting data can invalidate a law as easily as a theory.That's not to say that some theories are not more firmly established than others. Geocentric theory (the sun and planets orbit the earth) has no remaining evidence whatsoever and has been completely invalidated. String theory (from particle physics) is still struggling to produce sufficient evidence to become accepted, and it might yet end up on the scrap heap of scientific history. Einstein's theory of relativity is extremely well established and very widely accepted because it has made predictions that have been verified at every turn. (And yet we still don't call it a law!) Thermodynamic laws are extremely well established and verified, and are also very mathematical, and calling them laws seems to make sense.You could further verify how irrelevant the theory vs law label is by finding how various theories and laws are referred to in other languages. I'll bet you'll find a great deal of variation, that in some languages some theories that we call theories are called laws, and vice-versa. Some languages might have fewer or greater labels of distinction. But theories and laws are like snow. Whether you call it hardpack or powder or mash potatoes or any of a number of different terms, it's still snow.In other words, the hierarchy of certainty that would place law above theory does not exist.And finally, to bring this back on topic, this discussion of theory began when you responded to JonF with "Allegedly and Theoretically" in the other thread. I responded in Message 262, and I hope you had a chance to read it because it contains some useful information regarding the nature of theories, and some suggestions for how to respond constructively to JonF.--Percy

Unless things have changed dramatically since I was in school, only the lower ranks of colleges have teachers without doctorates, and they're not called professors. If this American student had attended Middlesex Community College or Daniel Webster College or the like (hopefully the names are indicative of these institution's lack of prestige and high academic standards), then many of his teachers probably didn't have doctorates, and it is unlikely that he called them professors.But if he went to any respected academic institution, and not just MIT and Stanford and Carnegie Mellon and Michigan and Harvard and Princeton and Yale and Cal-Tech and so forth, but also the University of Massachusetts and Lehigh and Texas A&M and the University of California and on and on, then he had professors with PhD's. This is probably true of at least the top couple hundred colleges and universities in the US.The more prestigious the university, the more stringent the requirements upon professors to engage in research and publish in the journals, from which derives the old saw, "publish or perish". Professors without PhD's would never be hired into any college or university with research aspirations, because a PhD is how one demonstrates his potential for carrying out original research.--Percy

Just so I can make sure my kids never apply to any institutions that hire people without PhD's into professorial positions, what were these universities? --Percy

We know that the mutations occurred during the bacterial reproductive process because these experiments have also been performed on bacterial populations raised from a single bacteria. Any genetic differences in the population had to have arisen through mutation, in other words, inaccurate copying of the DNA during reproduction. And the DNA has been sequenced to find the precise mutations that confer the resistance. What part of bacterial evolution don't you accept? That mutations happen? Or that the bacteria best suited for the environment are more likely to reproduce and least likely to die?Just to confuse the issue, let me also comment on this: Experiments indicate that some organisms increase their mutation rate in response to environmental stress. And some mutations are more likely to occur than others simply because of the gene's particular location on a DNA strand. For example, nucleotides that occur at tight bends in the DNA can be more prone to copying mistakes.--Percy

He meant perspicacity.--Percy

You don't quote what you're responding to, Message 1 doesn't specifically mention natural selection, and no recent post mentions it, so it's hard to tell who you're correcting.Anyway, I agree with you that it would be an error to call natural selection evolution. Natural selection is an aspect of evolution. When there's a desire for brevity, evolution is often described as descent with modification through natural selection. Of course, there's more to it than that, but it's a good starting point. By "kind" I'm guessing you mean the Biblical kind from Genesis. The term "kind" has no formal definition within biology, so before I'd feel comfortable in a discussion using that term you'd have to provide a firm definition. The definition of species is complicated enough without introducing a term with no formal definition.If we define macroevolution as change from one species to another, then macroevolution has been observed, both in the wild and in the lab. But if we define macroevolution as change from one kind to another, then I have no idea what that means.You can't define kind by simply providing examples, such as dogs and hyenas are different kinds but dogs and wolves are the same kind. That doesn't help. As an example, the definition of species when sexual reproduction is involved says that a species is a breeding population of organisms, and that species boundaries occur when the organisms are incapable of interbreeding. The full definition is more detailed, of course, since dogs and wolves are different species but can interbreed. Anyway, we'd need a similarly detailed definition of kind. It would have to have a set of criteria that we can apply to organisms in general to determine whether they're the same or different kinds.--Percy