1. Broncos (11-3)Tebow-mania is a long-lost memory. Peyton Manning has the Broncos on a nine-game winning streak and their lopsided road triumph over the reeling Ravens showed that this team is a legitimate Super Bowl contender.Nick Wass/Associated Press
The contest is accepting entries in one or all of four categories: wildlife, landscapes, underwater and aerials. The grand-prize winner will receive $10,000, publication in National Geographic Magazine and a feature on National Geographic’s Instagram account.