news aggregator

Edit or's note: In light of the recent death of Martin Gardner, we are republishing this article from the August 1998 issue of Scientific American. Gardner wrote the "Mathematical Games" column for Scientific American from 1956 to 1981, and continued to contribute columns on an occasional basis for several years afterward . This article, which includes four puzzles by Martin Gardner, was his final piece for the magazine.

My “Mathematical Games” column began in the December 1956 issue of Scientific American with an article on hexaflexagons. These curious structures, created by folding an ordinary strip of paper into a hexagon and then gluing the ends together, could be turned inside out repeatedly, revealing one or more hidden faces. The structures were invented in 1939 by a group of Princeton University graduate students. Hexaflexagons are fun to play with, but more important, they show the link between recreational puzzles and “serious” mathematics: one of their inventors was Richard Feynman, who went on to become one of the most famous theoretical physicists of the century. [More]

Can aquatic snails better remember lessons learned when they are hopped up on methamphetamine? Barbara Sorg of Washington State University in Pullman teamed up with Ken Lukowiak of the University of Calgary Medicine to see if working with snails might provide clues as to why drug memories are so strong that they seem to draw addicts back into repetitive use and addiction . [More]

Numerous recent studies have undercut the purported benefits of various herbal supplements. Gingko , echinacea and Saint John's wort , have all been found relatively ineffective against many of the ills they have been claimed to help. [More]

By Eric Hand

Did a large, icy comet smash into Neptune two centuries ago? That's the picture that is emerging from the latest measurements of gases in the atmosphere of the giant blue planet.

At a meeting this week of the American Astronomical Society in Miami, Fla., Paul Hartogh, project scientist for the Herschel mission, the European Space Agency's infrared observatory satellite, described the mission's first results for the Solar System. [More]

Back in the days when better living through chemistry was a promise, not a bitter irony, nylon stockings replaced silk, refrigerators edged out iceboxes, and Americans became increasingly dependent on man-made materials. Today nearly everything we touch--clothing, furniture, carpeting, cabinets, lightbulbs, paper, toothpaste, baby teethers, iPhones , you name it--is synthetic. The harmful side effects of industrialization--smoggy air, Superfund sites, mercury-tainted fish, and on and on--have often seemed a necessary trade-off.

Three years ago, the allure of the lemur brought Meredith Barrett to Madagascar.

The Duke University doctoral student was fascinated by the island, one of the world's most threatened biodiversity hot spots, and wanted to look at the impact of human development on the endangered primates that reside there.

Sprawling blooms of cyanobacteria have swathed the surfaces of lakes and oceans around the world for billions of years. But the serene, blue-green algae may be leaching a neurotoxin into the aquatic food chain, according to a study published May 3 in Proceedings of the National Academy of Sciences ( PNAS ). The report revived a nearly 50-year-old debate over the role, if any, of the toxin in the process of neurodegeneration.