A restoration of Titanoboa (foreground) in its natural setting. (By Jason Bourque, image from Wikipedia.)

When I was growing up I used to spend hours poring over the Time/Life series of nature books in my little library, absolutely enthralled by images of strange creatures from all over the world, but one photograph was particularly arresting. A grainy black-and-white double-page spread showed an anaconda that had wrapped its crushing coils around a caiman and a tree, slowly squeezing the life out of the crocodylian. Without any frame of reference for size it was easy to envision the two animals as giants, but that was just my b-movie fueled imagination running wild. Even though both anacondas and caimans