Creating a theory, part II

Another post below led to a number of comments, and I really can't do them justice in the space YACCS provides. So I'll address them here.

First a note: my scientific background is in the "hard sciences". I'm used to being able to whip something up in a lab. I understand that that commonly causes conflict of sorts, as John Maynard Smith noted in one of his books - he came from a hard science background to the study of evolutionary biology. If biologists must settle for lower standards of proof than I am used to, so be it.

Notice that my claims have been very modest, as noted here. I certainly didn't claim that no evolution of any form had ever occurred. What I wrote was "But until those discoveries are made and successfully peer-reviewed, claims that evolution progressed from the first life forms and culminated in the development of modern man remain speculation, which places them on par with creationism." That last clause might be controversial, but I don't see any problem with the rest of the statement. I will refer to this below as The Theory. And it's no straw man.

One problem I have with The Theory is in another post, about "what is a species?". Some of the definitions of species in the links (which no one has questioned) sound a lot like the Supreme Court definition of pornography - "I know it when I see it". Biologists may be trying to get a handle on something very slippery, but then that should tend to moderate claims, causing you to shy away from The Theory. Because if you can't even come up with a solid, universally applicable definition of a species, how can you ever say when speciation has occurred? If you're allowed to change the rules as you go, you can create circumstances in which evolutionary theory becomes unfalsifiable.

Mike Gannis asks several questions, one regarding the age of the earth. I'm agnostic. I really don't care much about the age of the earth, and I fail to see that it has much impact on my life or that of schoolkids. I'll just note that proof that the earth were fairly young would be bad news for The Theory, because it needs lots of time to work.

As for species in the fossil record, this goes back to the species definition problem again. We have found various fossil evidence that is found nowhere else in particular strata of the earth's crust, and various dating techniques give us an idea of how long ago these strata were deposited. If these species did not occur in earlier strata either, that would suggest that they had to have developed in a time period between that of the earlier strata. Or it might just mean that you haven't looked in the right places. That they haven't been found doesn't mean that they don't exist. I'll bet you a coelacanth that you'll find that some of those species were around if you look long enough.

We don't need The Theory to explain extinctions.

Apparently emergent species might be explained by migrations. I suppose if you looked in the Great Lakes and didn't know that sea lampreys already existed somewhere else, you might think that they had evolved there over the past century. Likewise for Corbicula, the obnoxious little clams that foul up heat exchangers and sprinkler systems.

The bottom line is that the claims for The Theory appear to have outrun the evidence. If you can't establish by exhaustion that certain species didn't exist before a certain point in time, tough luck - you don't have all the evidence you need. If it happens on long time scales, again, that's a problem for the proponents of The Theory to deal with before they make exorbitant claims - don't blame the rest of us.

Paul Orwin states that evolution is obvious on the scale of insects and microbial life. Other exceptional things happen to those critters too that cannot be applied to higher species, and again, what about that definition of species? Changes in color distributions, markings, etc, don't necessarily mean anything - they might just be expressions of other previously unsuspected capabilities of existing genotypes, and nobody is going to claim we have that figured out yet.

Incidentally, I'm not working from some sort of cheat book. I own books on all sides of this issue, and I've even read some of them, but I'm doing my own thinking and surfing here.

I would like to thank the participants for generally keeping the noise level down - I was prepared to cut messages ruthlessly if necessary, but that never became necessary despite the controversial subject.