Vermont island features oldest coral reef

ISLE LA MOTTE, Vt. - To the uninitiated, the flat rock slabs found across the center of this island at the northern end of Lake Champlain appear to be nothing more than giant stones.

But the rocks offer a history of the last half billion years of this area, which was washed by a warm equatorial sea and saw long-extinct plants and animals congregate in what is believed to be the earliest ancestor of modern coral reefs.

The walls of the now-preserved Fisk Quarry offer a vertical timeline — in stone — of the different layers of fossilized plants and animals that inched their way north as the world's continents drifted into their present locations.