Quotes of the Day

Man has a long habit of tinkering with his natural habitat, often with unintended or unfortunate results. Kudzu, for instance, planted in the United States to prevent soil erosion in the 1940s, went on to entangle telephone poles, trees and fences over seven million acres of the American South. Gypsy moths, a pest that devours oak and aspen trees, were originally brought to the U.S. in 1869 to breed stronger silkworms. But as our understanding of biology and genetics grow more sophisticated, so do our attempts to use plants and animals to rein in threats in our environment. The trick will be keeping the latest fixes from coming back—sometimes literally—to bite us.

An End to Dengue?
Australian scientists working with Vietnam's Ministry of Health are experimenting with tiny, one mm.-long crustaceans called MESOCYCLOPS, which fight dengue fever by eating the larvae of mosquitoes that carry it. Villagers in Vietnam transferred the shellfish into mosquito breeding grounds where they are not usually found. Dengue is notoriously hard to eradicate but since 2002, there have been no cases of the disease in test areas. Still, scientists are cautious about widening the program to other regions: in Africa, "Mesos" are carriers of the notoriously parasitic Guinea worm

Seeing Red
A Danish biotech company has developed a new way to detect land mines using genetically modified THALE CRESS, a member of the mustard family. The plant turns a deep red when exposed to nitrogen dioxide, a gas released by mines. The grow-anywhere green, which scientists propose to sow from airplanes or handheld seed-shooters in heavily mined areas, could prove an inexpensive and safe solution for land mine detection—a boon to countries like Cambodia, which harbors an estimated four million mines

Killer Fly
Instead of spraying another kumquat tree with insecticide, Taiwan and Hong Kong could consider turning to Florida for an eco-friendly way to fight their recent invasion of fire ants. The Sunshine State's weapon: the PHORID FLY. Phorid larvae, almost invisible to the naked eye, burrow into the ant's head, grow and eventually decapitate it. The flies themselves are harmless to humans and animals

Two Frogs Make a Right?
When Australians imported cane toads from Venezuela in 1935 to eat the beetles that were destroying sugar cane crops, they didn't count on the poisonous amphibians going after kookaburras, snakes and native cats instead. Now, after decades and millions of dollars spent trying to eradicate the man-made plague, a solution may be at hand: the DAHL'S AQUATIC FROG, native to Australia, can swallow infant and tadpole cane toads without any apparent ill effects—not bad, considering a grown cane toad can kill a dog in 15 minutes

• Hanna Kite
• Getting more sophisticated about fighting nature with nature