Evolutionary convergence

Stephen Jay Gould

One of the most spectacular controversies to have arisen in biology at the end of the 20th century was that between two famous biologists: the American Stephen Jay Gould and the British Simon Conway Morris. The controversy began with the former's book, published in 1989, Wonderful Life: The Burgess Shale and the Nature of History, to which Conway Morris responded in 1997 with another book, The Crucible of Creation. As the subtitle of Gould's book indicates, both biologists based their work on the discoveries of the Cambrian fauna of the Burgess Shale (Canada), which I referred to in another post, and which was discovered and studied precisely by Conway Morris.

In his study, Stephen Jay Gould focuses in particular on the surprising and abrupt diversification that took place 550 million years ago and left its mark on the Burgess Shale fauna to argue that evolution is dominated by the effects of chance, so that, if we rewound the history of life and repeated the evolutionary process, the results would not resemble anything we have now. As a corollary, if there is animal life on other worlds, around other stars, it won’t resemble anything on Earth. And if there is intelligent life outside Earth, their physical appearance will not resemble ours.

Cyclic Time and Linear Time

Stephen Hawking

In an article published in 1999, in volume 879 of the Annals of the New York Academy of Sciences, Pier Luigi Luisi speaks about the two traditional models of time that have been considered by traditional philosophy and the mythologies of various historical civilizations. They must not be confused with the two philosophical models originated in the twentieth century, the time A and time B of which I spoke in another post of this blog.

• Cyclical time, predominant in Asian civilizations and the Greco-Roman world until the Christian world view took root there. The origin of this model is evident, for many natural phenomena are cyclical: sunrise and sunset; the phases of the moon; the annual movements of the stars, synchronized with the seasons and with many biological phenomena...
• Linear time, prevailing in the three religions who consider themselves descendants of Abraham: Judaism, Christianity and Islam. Linear time can be compared with the course of the life of a living being, which begins at birth, goes on with changes during a certain period, and ends with death.