Selaginella genome adds piece to puzzle.

• Position: Plant Evolution

The sequencing of the Selaginella moellendorffii (spikemoss) genome--the first for a nonseed vascular plant--is expected to give scientists a better understanding of how vegetation of all kinds evolved over the past 500,-000,000 years and could open doors for the identification of new pharmaceuticals. American botanist and plant pathologist Jody Banks led a team of almost 100 scientists from 11 countries to sequence Selaginella, a lycophyte, which are the oldest living vascular plants. They shed spores to reproduce and have a singular vascular vein through their leaves, as opposed to more complex vascular plants.

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"There are only three families and about 1,000 species of lycophytes remaining. Selaginella has been on Earth about 200,000,000 years," says Banks, whose findings were published in Science. "This plant is a survivor. It has a really long history and it hasn't really changed much over time. When you bum coal, you're burning the Carboniferous relatives of these plants."

Banks explains that the Selaginella genome, with about 22,300 genes, is relatively small. Scientists also discovered that Selaginella is the only known plant not to have experienced a polyploid event, in which it creates one or more extra sets of chromosomes. Selaginella is missing genes known in other plants to control flowering, phase changes from...