Hi ahp:
Sounds like you have an interesting class going there.
Just a few thoughts:
Lamarck: Although Nosey brought up August Weismann's late 19th Century rat experiments, the Lamarckians countered by stating the experiments were flawed since they claimed Lamarck’s ideas were that the organism striving in its environment makes the inheritable changes, not external factors like chopping off tails, so it might not be a good idea to use that.
One thing you might be able to do (if you're clever enough), is to actually turn Lamarck into a witness FOR Darwinism (if the others are arguing creationism). Check out SJ Gould’s The Panda’s Thumb, especially pages 76-84. He discusses what Lamarck REALLY said. Basically, Lamarck argued that life is generated, continuously and spontaneously, in very simple form. It then climbs a ladder of complexity, motivated by a "force that tends incessantly to complicate organization." This force operates through the creative response of organisms to "felt needs." But life cannot be organized as a ladder because the upward path is often diverted by requirements of local environments; thus, giraffes acquire long necks and wading birds webbed feet, while moles and cave fishes lose their eyes. Inheritance of acquired characters does play an important part in this scheme, but not the central role. It is the mechanism for assuring that offspring benefit from their parents' efforts, but it does not propel evolution up the ladder.
If it gets that far, you might want to point out that the only real difference between Lamarck and Darwin was the fact that Lamarck proposed a one step process, whereas Darwin had two. In other words, they both agreed that organisms adapt to their changing environment over the generations, (which is anathema to the creationist position), but disagreed over the mechanism. Lamarck thought that organisms perceive the environmental change, responds in the "right" way, and passes its appropriate reaction directly to its offspring. Darwin observed that variation in local populations and then saw selection as the mechanism for how the reaction changes a population by conferring greater reproductive success upon advantageous variants. Lamarck pushed for directed evolution, Darwin for undirected change. You might be able to defuse Lamarck this way.
Witnesses: Are you limited to pre-1900 witnesses? If not, you might want to excuse Kettlewell. A good lawyer would be able to cast aspersions on his credibility by pointing out that the famous photos were faked (i.e., the moths were pinned to the branches — posed). It’s tangential, and irrelevant, but could drag the conversation easily off topic. It doesn’t change the validity of the observation (of the action of natural selection on the moth population), but could cause problems in the cross-examination. If you have a choice, I’d use Peter Grant as a witness — his 30 year study of
Gospiza spp in the Galapogos is definitive, real time, natural selection (see the book The Beak of the Finch).
Other: It’s not totally clear what the paleontologist will be arguing on the creationism side. The only two things I can think of would be punk-eq vs gradualism, and transitional fossils. On the former, prepare some rebuttals along the lines of pointing out that punk-eq is simply faster gradualism, the fossil record isn’t fined grained enough to show gradualism but there is no reason to assume that the organisms didn’t exist, etc. Also prepare some good transitional series (whales, horses, fish-amphibian are pretty good). Make sure YOU define what transitional really means to forestall a typical creationist strawman.
I can’t imagine what a farmer would be doing on that side — Darwin used much of the evidence from husbandry and breeding from farmers, pigeon fanciers, etc to show how selection worked. The only real extrapolation from that is based on time and the forces used (i.e., natural vs. artificial selection).
If you can give me more specifics on either your side or your opponent's case, maybe I can help out more. I'd also appreciate it if you'd give us the point by point on the action when your "case" actually goes to "trial".
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