There's plenty of hard evidence but none more so than how excited they get about birds at their feeders! I was in DC for three weeks caring for my Mom after surgery. I did not do one single, solitary tourist thing while I was there. I didn't set foot on The Mall. I didn't see a single museum. But I did buy a tripod and take pictures of birds. And some flowers. And a couple of cute kids. And now I'm just wondering what that says about me.