New York: Norton, (1993) dj. Hardcover first edition - The sixth volume of his essays - 31 essays on "the disparate but related issues of time, change, and organic evolution. Gould critically explores a cascade of ideas that shed new light on ecology, human nature, vertebrate anatomy, neo-Darwinism, and mass extinctions " Illustrated with drawings. Bibliography, index. 479 pages. ISBN: 0-39303416X.