Billion-year-old fossil believed to be an ancestor of Earth's first plants

(CNN)A group of paleontologists say the tiny freckles they found on a rock could hold the key to understanding the origins of plant life on earth.

The freckles, Virginia Tech researchers say, are actually billion-year-old seaweed microfossils. They substantially push back the current record of the multicelluar green plant by nearly 200 million years, according to the study published on Monday. Previously, the oldest known fossilized green alga was 800 million years old.

The fossils are so tiny -- about 2 millimeters in length or the size of a flea -- that they are barely visible without a microscope. But despite their miniscule size, researchers said the microplants may have contributed to the evolution of the land plants that appeared nearly 550 million years later. Read full article.