A rare sighting in Colombia's high Andes is giving conservationists an important new clue in the effort to protect one of South America's most elusive wild cats. According to Earth.com, camera traps set up in March at El Danubio, a conservation property outside Cali more than 6,560 feet above sea level, captured images of a tigrillo with a nearly all-black coat. The animal, also known as a northern tiger cat or oncilla, is already notoriously di…