plant fossil

[from Latin American Herald Tribune, 10/16/10]

Scientists Discover Fossil of First Plant in Argentina

BUENOS AIRES – A team of Argentine and Belgian scientists have discovered in northwestern Argentina a 472-million-year-old fossil of the first plant to grow on land, one of the researchers told Efe on Tuesday.

To date, scientists had believed that the first land plant had developed about 462 million years ago in the Middle East and Europe, but the new find would move that date back in time by “some 10 million years,” according to Susana de La Puente, who works with the Argentine Institute of Snow, Ice and Environmental Research.

The scientists found the fossilized spores of the primitive plant, called “cryptospores,” and they believe they have good evidence that the plant – a liverwort, that is to say a very simple plant that lacks stems or roots – is the ancestor of all terrestrial plants that evolved later.

The investigation, which was just made public in the scientific magazine New Phytologist, began in 2002 with the collection of sediments from the Rio Capillas river basin, about 1,500 kilometers northwest of Buenos Aires.

In the sediment samples, the scientists found fossils of five types of spores from five different liverworts, all of them land plants, and laboratory analysis of them was completed this year.

The scientists feel that the liverwort was the first terrestrial plant to evolve from plants that were growing in the sea.