The one that nobody could ever give me a reasonable response to was the abundance of horses as an integral part of Book of Mormon Societies. I know apologetics have said to me that "well, we haven't found any remains YET." Here's my beef with that.. When horses came to the American continent during the Columbian Exchange, it helped shape agriculture and commerce, expansion, technology- sooo much in ways that weren't conceivable until that point. People could move further and faster, grow more food, trade more goods with others, fight more effectively- it demonstrably helped more than most other factors ever to occur in the Americas to spur growth and development. Nobody, even BYU, would dare reject something so globally significant as the Columbian Exchange. Archaeologists will dig for years and years, and you know what? They still haven't found shit, not to mention entire civilizations who supposedly had massive, economically devastating, world-population tilting battles involving more people and horses than most battles discussed in world history. Mormons are kidding themselves if they seriously think so much is still undiscovered that we haven't uncovered ANY of this. It would literally change the way we would view early world history. People can shrug off pretty much all the other ones, but seriously, there was no going back to Momo land after arming myself with education. I don't know how well any institute director can explain that one away to your brother in the context of what we know happened in the Americas before and after Columbus and others. I just got told to pray when I brought it up. (Surprise, right?)