Genetic Amniocentesis
The fluid that surrounds a fetus in the uterus can now be examined for the prenatal detection of genetic disorders, yet the procedure is being performed for only a tenth of the parents most in need of it...
Features
Basaltic Meteorites
Eucrites and shergottites are remarkably similar to volcanic rocks on the earth and the moon, but they are from somewhere else. They testify to the long history of volcanic activity in the solar system...
Computer Backgammon
Backgammon is a good test of principles of artificial intelligence. BKG 9.8 is the first computer program to defeat a world champion at any board or card game
The Functioning of Blood Platelets
These small bodies act to stop the Row of blood from a wound. The interactions of their contents with substances in the blood plasma and in tissue play complex roles in health and disease...
Gauge Theories of the Forces between Elementary Particles
All the basic forces of nature are now described by theories of this kind. The properties of the forces are deduced from symmetries or regularities apparent in the laws of physics
Ice-Age Subsistence in Northern Spain
A 12,000-year record of man's quest for food in Pleistocene times has been found in a cave near the Bay of Biscay. Changes in the use of resources suggest a response to increasing demographic pressure...
The Deep-Earth-Gas Hypothesis
There is much evidence indicating that earthquakes release gases from deep in the earth's mantle. Such gases may include methane of nonbiological origin, which could be a vast resource of fuel...
Sexual Selection in the Black-tipped Hangingfly
This species has evolved a striking form of mating behavior: females choose males on the basis of the prey they present during courtship, and males may mimic female behavior to steal such prey hom rivals...
Departments
50 and 100 Years Ago, June 1980
Science and the Citizen, June 1980
- Letters
Letters to the Editors, June 1980
- Recommended
Books, June 1980
- Mathematical Recreation
Mathematical Games, June 1980
- Amateur Scientist
The Amateur Scientist, June 1980
- Departments
The Authors, June 1980
Bibliography, June 1980
