1970s: New government laws are being passed to restrict water and air pollution and to protect forests and endangered species.

Today: Few new environmental laws are passed; instead, existing laws are repealed as being unfair to local businesses.

1970s: The activities of cells are considered to be among nature's greatest mysteries.

Today: Even with the recent completion of the Human Genome Project, all questions about cellular activity are not answered; however, scientists have a good sense of how information is transmitted throughout the body.

1970s: Americans are eating more and more beef: per capita consumption of beef rises almost 50 percent between the early sixties and mid seventies, when it reaches its all-time high.

Today: Knowledge about the effects of red meat on the body have caused a shift in the American diet to lighter meats; still, the nation's reliance on fast food has caused...