Bringing Order to the Fungus Among Us

John Roach
for National Geographic News
October 25, 2004
For mycophiles—hunters of wild, edible mushrooms—autumn is high time to don rubber boots, grab a penknife, and head outdoors.

"People in certain parts of Europe just love to go out when the mushrooms are out. They are really comfortable doing that, and they have knowledge about which ones they can eat," said Rytas Vilgalys, a biologist at Duke University in Durham, North Carolina.

Other cultures in the world are more wary when it comes to mushrooms, knowing that while some can certainly give a pasta sauce zest or tastefully garnish a piece of meat, others can just as easily kill with toxic poisons.

Vilgalys is part of a consortium of university scientists who aim, in part, to help sort out which mushrooms are safe to eat and which are best avoided.

The task is daunting. Mushrooms, along with molds, yeasts, lichens, and puffballs (which discharge spores in a smokelike cloud when pressed or struck) are all fungi. Scientists have identified about 80,000 species of fungi, a tiny fraction of the estimated 1.5 million.

In recent years scientists have published descriptions of thousands of species new to science in journals like Mycotaxon and Mycologia. But it was not until the advent of molecular systematics—using DNA to identify organisms—in the late 1980s that scientists began to see distinctions between structurally similar organisms.

In 2003 Vilgalys and his colleagues at the University of Minnesota, Oregon State University, and Clark University began collaborating on the National Science Foundation-funded Assembling the Fungal Tree of Life project.

The project uses molecular systematic methods in addition to traditional identification based on morphology—the form and structure of the organism. The project aims to significantly increase understanding of the evolution of the fungi, which has implications ranging from understanding how ecosystems function to discovering new drugs. It will also help scientists discover even more new species.

"One goal is to make sure we have all the data on the ones we know and then use that as a tool to assess what are the groups we don't know," Vilgalys said.

Fungal Importance

Fungi, according to the Assembling the Fungal Tree of Life consortium scientists, are of much use—and abuse—to humans and thus warrant a deeper understanding. Fungi cause diseases and cure diseases; they help make beer and bread; they play a role in indigenous cultures; and they provide a range of ecological services.

"They sort of figure into people's lives everyday, including air quality, yet we still don't know which fungi are doing what we are concerned about," Vilgalys said.

Examples of potential benefits from the Assembling the Fungal Tree of Life project include helping scientists find a way to deal with the chytrid fungus that is attacking frogs around the world and causing their populations to crash.

The study of fungi could also lead to the discovery of new drugs. Fungal-produced drugs discovered to date include antibiotics like penicillin, cephalosporins, and griseofulvin, which is used on athlete's foot and ringworm.

"And everyone agrees fungi are essential components of the environment," Vilgalys said. "They are the only thing that can degrade lignin plant material [which helps give plants rigidity]." Without fungi, piles of fallen leaves and wood would lay only partially decomposed on the forest floor.

Fungal Tree

Once completed, the "fungal tree of life" will serve as a sort of road map to fungal diversity, allowing researchers to approach fungal studies with the knowledge of how various groups within the fungal kingdom are interrelated.

For example, a researcher interested in a disease-causing organism could look at the tree and find the most closely related non-disease-causing species to help tease out the genetic traits that cause the disease, Vilgalys said.

In addition to discovering new drugs and compounds of use to the biochemical industry, Vilgalys also hopes the Assembling the Fungal Tree of Life project will provide amateur mycophiles a better appreciation for what is out there.

"Recreational mushroomers are mainly concerned with macro fungi—the mushrooms, the things they can see, touch, and feel. Knowing something about their relationships or their ecology just gives us a higher sense of why these things are interesting," he said.

Don't Miss a Discovery
Sign up for the free Inside National Geographic newsletter. Every two weeks we'll send you our top news stories by e-mail.

For more fungus stories, scroll to bottom.

© 1996-2008 National Geographic Society. All rights reserved.