HEATHER STONE / Chicago Tribune Stephanie Stone (right) watched her three daughters play with girlfriends on a trampoline on Canada's Aamjiwnaang First Nation reservation. A study shows girls are being born at twice the rate of boys on the reservation.

Once there was a kids' hockey team on the reservation of the Aamjiwnaang First Nation in Canada just across the border from Michigan. No longer. There aren't enough boys. This community, surrounded by dozens of pollution-spewing chemical plants, is an extreme example of a puzzling phenomenon playing out across the world, in countries as diverse as the United States, Sweden and Japan.

Frank Kramer is getting out of long-range forecasting. As the winner of Weather Watch's annual Precipitation Prediction Contest, he's going out on top. It would be hard to beat his performance. Last fall, he predicted that Lindbergh Field, San Diego's official weather station, would receive 7.23 inches of rain from July 1, 2007 through June 30, 2008. The total ended up 7.25 inches. If 0.02 of an inch hadn't squeezed out of a surprisingly deep marine layer on the afternoon of June 4, he would have been exactly right.

Some songbirds figure out the best place to nest by eavesdropping on the singing of birds that have successfully hatched babies.