Deforestation in the Tropics
Government policies that encourage exploitation-in particular excessive logging and clearing for ranches and farms-are largely to blame for the accelerating destruction of tropical forests...
Features
What is Happening at the Center of Our Galaxy?
This mysterious region contains antimatter, radioactive clouds, veiled sources of intense radiation, swirling gas and dust and an unseen object with a tremendous gravitational pull-perhaps a massive black hole...
The Unusual Origin of the Polymerase Chain Reaction
A surprisingly simple method for making unlimited copies of DNA fragments was conceived under unlikely circumstances-during a moonlit drive through the mountains of California
Impact Cratering on the Earth
The explosion of the world's nuclear arsenal could not match the power released when a kilometer-size meteorite hits the earth. Have impacts even more powerful altered biological as well as geologic evolution?...
Advanced Light-Water Reactors
New designs that include "passive" safety features can make nuclear power more attractive, but only if attention is paid to economics, effective management and rigorous training methods...
What the Brain Tells the Eye
A circadian clock adjusts the sensitivity of the horseshoe crab's eyes. Study of the mechanism opens a window on the brain's control of sensory organs in other animals as well
The Transformation of the Kalahari !Kung
Why after centuries of stability has this society, an apparent relic of ancient hunting and gathering groups, abandoned many of its traditional ways?
Ancient Glazes
The beauty of a glazed ceramic arises from the interplay of light with the complex structure of the glaze. The methods of materials science reveal the ingenuity of ancient glazing technologies...
Departments
50 and 100 Years Ago: April 1990
Slow Boat to Mars
Right to Lie?
Acid Test
Zap!
Science Behind the Wall
All about Eve
Gone in a Flash
Green Thumbs
Net Result: Folded Protein
Space Invaders
Tone of Relief
Mandelbrot Set-To
Milliken & Co.
Of Mice and Men
Atmosphere of Uncertainty
Breakup?
Cashcowosaurus
- Letters
Letters to the Editors, April 1990
- Recommended
Books, April 1990
- Amateur Scientist
The Amateur Scientist, April 1990
- Departments
The Analytical Economist: Budgeting Smoke and Mirrors
Essay: A New Initiative to Save the Planet
