By Vidya Rajan, Columnist, The Times I was watching a male ruby-throated hummingbird at my feeder the other day. Hummingbirds fascinate me. Besides being charismatic and heart-stoppingly beautiful, they are feisty. I watched him drink his fill and then sit on a nearby branch to play dog-in-the-manger, chasing away other hummingbirds who dared to try to take what he didn’t want. Their speed, their...