Graduate student Megan Wyman and colleagues spent two summers hanging with a herd of wild bison in Nebraska, listening to them bellow and watching them do what birds and bees (and bison) do. The team reports an unexpected discovery.

It’s enough to make fitness experts despair. Despite all their efforts to get Americans to become more active, gym memberships actually fell 3 percent between 2006 and 2007. The good news: gyms around the country are offering deep discounts on memberships.