One of evolution's fundamental questions is how the skein of life on Earth remains unbroken yet is constantly renewed by new species. What accounts for the scientific paradox that all organisms and species are ephemeral, and yet life endures, yielding more advanced players in nature's eternal play? In this riveting work, renowned scientist Niles Eldredge presents a magisterial account of leading thinkers as they wrestle with this paradox over a span of two hundred years.

Eldredge begins in France with Jean Baptiste Lamarck, who in 1802 first framed the overarching question about new species. Giambatista Brocchi followed, bringing in geology and paleontology to expand the question. In 1825, at the University of Edinburgh, Robert Grant and Robert Jameson introduce these astounding ideas to a young medical student named Charles Darwin. Who can doubt that Darwin left for his voyage in 1831 filled with these daring, new ideas about the "transmutation" of species, well cultivated by earlier thinkers tilling this rugged and contentious intellectual ground?

Eldredge revisits Darwin's early insights in South America and his later synthesis of knowledge into the origin of species. He then considers more recent evolutionary thinkers, such as George Gaylord Simpson, Ernst Mayr, and Theodosius Dhobzhansky, concluding with the young, brash graduate students Niles Eldredge and Steven J. Gould, who set science afire with their revolutionary concept of punctuated equilibria and upended accepted evolutionary ideas. Filled with shattering insight into evolutionary biology and told with a rich affection for the tumult of the scientific arena, this new book is destined to become a classic in the field.