National Geographic : 2013 Apr
photos: Christian Grund, 13 photo (top); swiss Federal Materials testinG FaCility (eMpa) GraphiC: Álvaro valiÑo. sourCe: sirin yaeMsiri, unC GillinGs sChool oF Global publiC health Strings Theory Call it an encore. Fungi may be able to deliver the sounds of a stradivarius. violins work like this: bowed strings vibrate the bridge beneath them; the bridge moving against the violin’s body bounces sound. stradivarius violins from the 1700s are said to move the notes around best. according to tree pathologist Francis schwarze (above), applying two arboreal fungi—Physisporinus vitreus and Xylaria longipes—to a lesser violin can help it perform on a par with the famed maker’s instruments. the fungi work by thinning cell walls in norway spruce—the only wood used to make a violin’s top plates—and maple so that sound can move more freely. less weight means louder and more resonant tones. it’s not all about volume, though. the fungi also double the dampening function of the wood, taking away too-high, irritating sounds. schwarze says fungi can improve other instruments as well, including hammer dulcimers and guitars. —Johnna Rizzo a fungus applied to a violin’s maple plate thins cell walls (bottom), so sound travels better. president barack obama created César Chávez NatioNal MoNuMeNt in California, an area that includes the late activist’s former home. • australian researchers found that each mother fairy wreN teaches unhatched chicks a feeding “password” to help her identify her brood. • a species of PhytoPlaNktoN is the first known sun-fed organism that flees from predators, say scientists in rhode island. • a nether- lands study gauging reactions to armpit sweat suggests humans haven’t lost the ability to sMell fear. ET CETERA nEXT Fingernails grow about twice as fast as toenails.