Skip to main content

Features

The Search for Blood Substitutes

The threat of global shortages of blood and fears about contamination have hastened attempts to find life-sustaining alternatives. Several of these compounds look promising

By Mary L. Nucci and Abraham Abuchowski

The Origin of Birds and Their Flight

Anatomical and aerodynamic analyses of fossils and living birds show that birds evolved from small, predatory dinosaurs that lived on the ground

By Kevin Padian and Luis M. Chiappe

Greenland Ice Cores: Frozen in Time

Ice, frozen in place for tens of thousands of years, provides scientists with clues to pastand futureclimate

By Richard B. Alley and Michael L. Bender

Everyday Exposure to Toxic Pollutants

Environmental regulations have improved the quality of outdoor air. But problems that persist indoors have received too little attention

By Wayne R. Ott and John W. Roberts

The Viking Longship

Long, narrow ships packed with warriors helped to make the Vikings the dominant power in Europe for three centuries, beginning in about A.D. 800

By John R. Hale

Departments

Purchase To Read More

Already purchased this issue? Sign In to Access
Select Format