Emlen takes us outside the lab and deep into the forests and jungles where he's been studying animal weapons in nature for years, to explain the processes behind the most intriguing and curious examples of extreme animal weapons. As singular and strange as some of the weapons we encounter on these pages are, we learn that similar factors set their evolution in motion. Emlen uses these patterns to draw parallels to the way we humans develop and employ our own weapons, and have since battle began.