First, I'm really impressed with Darwin's writing. I wish modern research results were presented in as readable and understandable a way. Yes, he's using rather flowery Victorian prose, and he tends to overuse the semicolon and the hyphen--but then, there are a lot of people who do that today, and some of them run the government. And at least he's managed to refrain from quoting anything in French (or, worse, German...) since the "Historical Sketch." And at least he doesn't capitalize random words.
Second, I've been very interested to see exactly how much Darwin didn't know--and, given how much he didn't know, how much he got right. It's mind-boggling to think that he managed to get the main ideas right when he didn't even know about genes. (A friend of mine recently told me that they found a copy of Mendel's paper on Darwin's desk after he died--apparently, he just didn't get around to reading it. Imagine what he might have done with Origin if he had!)
On his blog, John mentions that he scribbled in the margins of his book the modern terms for the concepts Darwin presented in chapter 3. I have to admit, I was tempted to do the same thing in my copy (although the thought occurred to me back in chapter 1). I find it fascinating that many of the ideas that Darwin apparently had to defend are taught in high-school biology today. For example, consider this, from chapter 1:
Indefinite variability...has probably played a more important part in the formation of our domestic races. We see indefinite variability in the endless slight peculiarities which distinguish the individuals of the same species, and which cannot be accounted for by inheritance from either parent or from some more remote ancestor.Mutations, anyone?
John points out several other examples from ecology.
I was also reassured to learn that the debate about what constitutes a species has been going on since before Darwin. I was tempted to think that it was the offspring of the digital age--i.e., the need of modern scientists to cut into chunks things that are naturally continuous.
More to come...