MELISSA BLOCK, host:
From NPR News, this is ALL THINGS CONSIDERED. I'm Melissa Block.
If you like being alive, you might want to thank a plant. Plants and their microscopic relatives provide the oxygen we breathe. They're also one source of the energy that fuels the modern industrial world. And, of course, we eat them, too.
For scientists these days, probing the secrets of plants at the genetic level is all the rage. Here's NPR's Joe Palca to tell us about two especially interesting plants.
JOE PALCA: If you're wondering how exactly it is that plants help fuel the world, Jody Banks has the answer.
Ms. JODY BANKS (Botanist, Purdue University): When you burn coal today, or actually the fossil fuel, the fossil is a fossil of the relatives of Selaginella.
PALCA: Jody Banks is a botanist at Purdue University. Selaginella is smallish plant, about six inches tall. It's found all over the world. Banks says Selaginella represents an important step in the evolution of plants. It's one of the first to develop a system of tubing for transporting water and other nutrients from one end of the plant to the other.
Ms. BANKS: You can only reach a certain height before, you know, you have to be able to - you have to have tubing to conduct the water from the ground to the top of the plant.
PALCA: If you remember your high school biology, those tubes are called xylem and phloem, and plants wouldn't get far without them. Besides tubing, Selagninella has something else you should know about.
Ms. BANKS: Now we're going to talk about plant secondary metabolites.
PALCA: Okay, wait a minute. Let me get myself seated comfortably.
Ms. BANKS: Okay.
(Soundbite of laughter)
PALCA: Secondary metabolites are compounds that aren't absolutely essential for survival but are useful to have around. An example would be the scents of flowers or some chemical the plant makes that pests don't like. It turns out that these secondary metabolites have been useful in medicine. The anti-cancer drug Taxol is an example.
As Banks reports in the current issue of the journal Science, Selaginella is chockfull of genes that make these secondary metabolites.
Ms. BANKS: So what that means is that Selaginella is likely to make many, many, many secondary compounds, and they're most likely going to be unique.
PALCA: Another important plant getting a genomic working over is amborella. Victor Albert of the University at Buffalo says amborella doesn't look all that important.
Mr. VICTOR ALBERT (University of Buffalo): It basically just looks like a small tree or shrub with fairly non-descript leaves and relatively non-descript flowers, and it produces berries.
PALCA: But those non-descript flowers turn out from one of the first flowering plants that evolved on Earth.
Ms. PAM SOLTIS (Botanist, University of Florida): Somewhere around maybe 130 or more million years ago, the flowing plants first emerged. And the flower was a great innovation.
PALCA: Pam Soltis is a botanist at the University of Florida. Flowering opened up all sorts of new ways for attracting pollinator and spreading seeds hither and yon.
Soltis says amborella is a bit of a puzzle in the flowering plant world. Unlike the other early flowering plants, it doesn't have any direct descendants, sort of like the platypus, a relative of all mammals but the ancestor of none. But that also makes it useful to plant geneticists.
Ms. SOLTIS: It provides a reference point for orienting all of the other changes that have occurred within the flowering plants.
PALCA: The flowering plants may be more important to gardeners and farmers with their gaudy leaves and tasty fruit, but Jody Banks says she intends to keep her research focused on the more pedestrian Selaginella.
Ms. BANKS: It's a survivor. It's been around hundreds of millions of years. And who knows, if there's a next mass extinction, it may be what's left.
PALCA: So if amborella is the platypus of the plant kingdom, maybe that makes Selaginella the cockroach. They're supposed to be survivors, too.
Joe Palca, NPR News, Washington.