Scientific American Magazine

The composition of the U.S. labor force has been sharply changed by the influx of women. The failure of the economy to create enough jobs is aggravated by the poor quality of most of the jobs added since 1950

The Viking landers have completed their biological experiments. The experiments did not detect life processes, but they did reveal much of interest about the chemistry of the surface of the planet

In this system plastic pipes laid on the surface of the ground deliver water to plants drop by drop. The system reduces stress on the plant, conserves water and works well with saline water

Galaxies tend to form small groups, which in turn form larger clusters, and so on. Such a hierarchical organization has long been suspected, but only recently has it been clearly perceived

Cats have had a long association with people but have rarely been intentionally bred for specific characteristics. The distribution of their mutants thus reflects certain human tastes and movements

The microscopic examination of the working edges of certain stone implements used by ancient hunters makes it possible to distinguish among such uses as scraping hide, cutting meat and sawing wood

The fusion of a sperm and an egg triggers a series of transient changes in the concentration of ions that prevents the fusion of additional sperm and initiates development of the embryo

In the 16th century Britain ran out of wood and resorted to coal. The adoption of the new fuel set in motion a chain of events that culminated some two centuries later in the Industrial Revolution