A species of bioluminescent fungi looks unassuming as it pokes its capped head above the mossy wood from which it grows in the tropical forests of Brazil. But at night a chemical reaction causes the fungus to emit an eerie green glow sometimes called foxfire.
The 33 Mycena species known to glow in the dark are separated into 16 lineages, San Francisco State's Desjardin says.
"Obviously the big question then arises: Did luminescence evolve 16 different times in the genus Mycena, or did it evolve only a few times and was lost hundreds of times during the course of evolution?" he said in an email to National Geographic News.
To help answer this question, Desjardin's research team has been extracting and sequencing DNA from the glowing mushrooms. They will use the data to develop a mushroom "family tree" that includes glowers and related nonglowers, a first step to determining when bioluminescence emerged in fungi.