Question: Why garbage trucks, Hen? Why?

Darr shared this article with me the other day and I find it quite interesting as a parent of a young boy in love with garbage/recycling trucks. The title is awesome - The Evolutionary and Cognitive Basis of the Cultural Success of Garbage Trucks Among Western Toddlers. Seriously, that is one bad-ass title. I love that the author (Nicolas Baumard) is so excited his young son stayed focused on one thing for 18 minutes. Having a lil' monster, I mean, Bean, of my own I know how incredibly amazing it is when this happens. Here's one of the video links, you know, in case you have your own little garbage truck-lovin' son.