...neither medical schools nor pharmaceutical firms maintain divisions of evolutionary science.I thought I'd mention (from time to time) some of the ways in which chemicals derived from other organisms seem to serve a purpose (there's that word again, the one that has no place in the vocabulary of a naturalistic evolutionist) for human beings. At a minimum, I will be providing evidential support for Skell's claim above. Perhaps such evidence will also serve as a design argument (on yet another level), as I can't imagine a Darwinian "just-so story" for some of what I have in mind.
For starters, consider the Horseshoe Crab. A clotting agent derived uniquely from the blood of these strange-looking arthropods is used to test every intravenous drug administered to people. It's a test for purity from harmful bacteria, and no IV drug reaches your hospital pharmacy without first having passd the Horseshoe Crab test.
On a Christian worldview, this makes perfect sense. We are told that God created other life in part for our benefit, and so we search the living world for cures for human diseases. And such searching continues to reap benefits. But what I don't understand is how an evolutionary naturalist would ever expect this, or how he could justify beginning such a search. On his view, natural selection acts without purpose or design, and certainly doesn't evolve some life forms for the benefit of humans that don't even inhabit the same ecosystem. Moreover, the alleged common ancestor of humans and arthropods would have to have been very early in the history of life, and many of the intermediate life forms almost certainly lacked either the clotting compound of the "crab" or the intravenous drug use of the human.
This is, of course, just the first of dozens--perhaps hundreds--of examples that could be delineated. Besides just brute fact or lucky happenstance, can anyone suggest how a naturalist could explain these sorts of beneficial relationships?