THE DAY BEFORE AMERICA: Changing the Nature...

THE DAY BEFORE AMERICA: Changing the Nature of the Continent by William H. MacLeish, illustrated by Will Bryant (Houghton Mifflin: $11.95; 277 pp.) Mixing personal observation and scientific research, William H. MacLeish examines the changes humans have wrought in the flora and fauna of North America. He notes how animal and plant populations shifted with the last glaciers and examines the remains of the Clovis and Folsom cultures. Although their ancestors contributed to the elimination of the mastodons and other relict populations of Ice Age animals, Native American tribes enlarged the margins of the forests, resulting in the extraordinary wealth of game and edible plants that the New England colonists found. Since then, the record has largely been one of destruction, from the slaughter of the wolves to the extinction of the passenger pigeon.