No worries, David. Like I said, I like your inquisitive spirit. Curiosity is one of the best parts of life. It can be frustrating to bump up against orthodoxy, no matter where you find it, but at least in science, orthodoxy is usually backed up by a lot of evidence and research. Not always, but usually, and over time, theories either firm up or are discarded (or more likely, modified). For something like evolution, there are still plenty of questions that haven't been answered, but the broad strokes seem to be pretty solid. The Yucatan impact seems to have solid evidence behind it from a variety of angles, so I think it's highly likely that it's the right explanation. That said, we don't have videotape of the event, so I'm sure there are details we'll never know.
As to attention deficit, I don't struggle with that (at least, I don't think so), but one nice thing about Wikipedia is that you can kind of jump around in it and pick things up in bite-size chunks. I rarely read an entire Wikipedia entry; I usually skip around from section to section, looking for answers to specific questions. Give it a shot. Nobody's asking you to write a book report. :)
I love reading the discusions you've added so far. I don't have much of a science background, yet at the same time a great deal of passion for it. When I ask questions, it's mostly out of curiosity. Thanks for your replies.
Hi, I'm not sure I can see all the comments on the question. It's quite clear that the evolution of the brain was one of the most important aspects of homo sapient being homo sapient. The focus on the bones is quite natural for now I think because that's all there's left (and the most precious part of it - DNA)! And scientists like to touch and observe, while evolution of the brain takes a bit more speculation.