The Belknap Press of Harvard University Press, 1977 Cambridge, Massachusetts. 8ºM (21,5×14 cm) 453 págs. Rústica ilustrada. Cubierta rozada con dobleces. «A masterful exposition of what has come to be called «the synthetic theory» of biological evolution… strongly recommended as a text and a reference book, and for the general reader who wants to acquire a serious understanding of biological evolution.»