The Origins of New World Civilization
In the Mexican valley of Tehuacn bands of hunters became urban craftsmen In the course of 12,000 years. Their achievement raises some new questions about the evolution of high cultures in general
In the Mexican valley of Tehuacn bands of hunters became urban craftsmen In the course of 12,000 years. Their achievement raises some new questions about the evolution of high cultures in general
Evidence of a titanic explosion in the nucleus of a nearby radio galaxy suggests that such events may be responsible for a large part of the cosmic radiation striking the earth
An account of experiments showing that the changes in activity that constitute the behavior cycle are governed by interactions of outside stimuli, the hormones and the behavior of each mate
Its 10,000 atoms are assembled into four chains, each a helix with several bends. The molecule has one shape when ferrying oxygen molecules and a slightly different shape when it is not
The chainlike molecules of polyethylene have the cunous ability to disentangle themselves and form crystals. The study of nearly perfect crystals can suggest ways to improve all linear polymers
Rich in minerals and poor in organic matter, these soils are common in the Tropics. They present an obstacle to increasing the production of food in many of the underdeveloped nations
Performed in Cleveland in 1887, this famous experiment disproved the hypothesis of a stationary "luminiferous ether." The problems it posed led indirectly to Einstein's special theory of relativity
Everyone knows that his subjective sense of the passage of time can be influenced by circumstances. How much various circumstances affect this sense is explored by experiment