Follow that feather!

     Those of you who know me well know I have a soft spot for wild birds...so I found this story in today's N.Y. Times interesting. But even if you have no interest in the birds themselves, the technology is interesting and has broad applications for all of the biological sciences.
     Retail is already using tiny devices for tracking and security.
     People caring for elderly relatives can use tracking devices to make sure they don't wander off.
     And pet tracking as old hat by now.
     How long before the tracking bugs are so small that parents can hide one in their daughter's purse or son's wallet? And should they? There are already somewhat larger devices that can easily be attached to the kids cars. Are their persons next?