Brazil nut effect: why larger mixed nuts "float" to surface

Video link. While I'm thinking about particle physics, here's something that might interest those of you who puzzle over why the dried fruit often ends up on the top of your cereal, or why cashews and Brazil nuts often end up pouring out on top in a can of mixed nuts. It's because of a phenomenon called granular convection, also known as the muesli effect or the Brazil nut effect. Shaking the contents of a container effectively liquidizes them, causing the bigger ones to float and cluster together. The phenomenon has been of interest to scientists since the 1930s.