Amazon.com description: Product Description: Pp. vi, 250; some text-figures (maps, charts, phylogenies, cladograms, etc.). Original light brown cloth, lettered in gilt on the spine and front cover, 8vo. This edited volume contains a number of key papers - the most well-known is Eldredge and Gould's "Punctuated Equilibria: An Alternative to Phyletic Gradualism." This 35 page paper is the first publication of the evolutionary model of punctuated equilibrium. In the 21 century this model has achieved wide acceptance. From the library of paleontologist Brian F. Glenister with his signature on the front endpaper.