Gender Gap

From Brain Rules:

When girl best friends communicate with each other, they lean in, maintain eye contact, and do a lot of talking. They use their sophisticated verbal talents to cement their relationships. Boys never do this. They rarely face each other directly, preferring either parallel or oblique angels. They make little eye contact, their gaze always casting about the room. They do not use verbal information to to cement their relationships. Instead, commotion seems to be the central currency of a little boy's social economy. Doing things physically together is the glue that holds their relationships intact.

I found that to be pretty interesting, and mostly true, based on my own interactions and those I've observed between females in general.