The standard definition of a biological species does not apply to viruses. A more expansive and dynamic view of viral populations holds clues to understanding and defeating them
Sustaining the Amazon
Can scientists reconcile the inevitability of economic development with the preservation of rain forests?
Surgical Treatment of Cardiac Arrhythmias
To save the life of a doomed patient, the author and his colleagues developed a now standard surgical procedure for correcting lethally fast heartbeats in many people susceptible to them
Risk Analysis and Management
Inadequate approaches to handling risks may result in bad policy. Fortunately, rational techniques for assessment now exist
The binary logic of modern computers often falls short when describing the vagueness of the real world. Fuzzy logic offers more graceful alternatives
Edwin Hubble and the Expanding Universe
More than any other individual, he shaped astronomers' present understanding of an expanding universe populated by a multitude of galaxies
Australia's Polar Dinosaurs
Their excellent night vision and apparent warm blood raise a question: Could they have survived icehouse conditions at the end of the Cretaceous period?
Accurate Measurement of Time
Increasingly accurate clocks--now losing no more than a second over millions of years--are leading to such advances as refined tests of relativity and improved navigation systems