If you analyze aggregated cellphone traffic — as researchers at M.I.T., AT&T and I.B.M. did with United Statesdata from July of last year — interesting patterns emerge. Cities become connective hubs as people move to them from nearby counties and from far across the country. As a result, many calls originate and end in cities, connecting urban citizens to their families back home. At the same time, communities emerge that have little to do with geographic boundaries. While some follow state lines, others split states in half or combine them. Check the infographic after the break.

You can check a bigger version of this infographic here.