One day I decided to give my made-up students another activity.  I had realized that the dendritic structure of neurons and their branches in the brain are reflected in all sorts of other natural structures on Earth:  Have you ever noticed that roots and branches have a similar structure? Veins and rivers?  I came across information one day that called this structure "dendritic."  Another term that came up was "alluvial flow."  I decided to have my fictitious students choose one structure each and blog about it.  I found almost all this information on Wikipedia!  The way this page works is, when you see a box on the left that you want to read more of, click its counterpart on the mini-blog on the right and you will be able to read more!  Hover over Blog on the menu above and click on Alluvial Flows to come back here.  My muppet students are happy to show off what they've learned!