When is Seeing Believing?
Digital technology for manipulating images has subverted the certainty of photographic evidence
The Terror Birds of South America
These huge, swift creatures were the dominant carnivores of the continent for millions of years, until competitors drove them into extinction
The Molecular Architects of Body Design
Putting a human gene into a fly may sound like the basis for a science fiction film, but it demonstrates that nearly identical molecular mechanisms define body shapes in all animals
The Future of American Defense
U.S. forces were shaped for conflict with a superpower.
The emerging multilateral world calls for a smaller, more flexible and far less expensive military
Sulfate Aerosol and Climatic Change
Industrial emissions of sulfur form particles that may be reflecting solar radiation back into space, thereby masking the greenhouse effect over some parts of the earth
In the aftermath of the Superconducting Super Collider's death, physicists are divided over how--or even whether--they should continue their search for a unified theory of nature
Light, liquid-mercury mirrors, which can potentially be made much larger than glass mirrors, may enable astronomers to construct enormous telescopes and see farther than ever before
AIDS and the Use of Injected Drugs
The AIDS epidemic continues to grow among drug users who inject. It could be curbed if governments more readily adopted effective prevention programs