A Lateral View of Darwin
Papacosta, Pangratios, Journal of College Science Teaching
Last year, we celebrated the 200th anniversary of the birth of Charles Darwin (18091882); it has been approximately 150 years since the publication of On the Origin of Species on the theory of evolution by natural selection. As my contribution to this celebration, I offer a few peripheral thoughts that speak of the value of interdisciplinary thinking, parallel revolutions, and the nature of science.
It was the book Principles of Geology by Charles Lyell that gave Darwin the long-time scale he needed to make his theory viable. With a time scale of hundreds of millions of years, even the tiniest biological change could, in the long run, produce a major evolutionary transition. From An Essay on the Principle of Population, a book by Thomas Malthus, Darwin identified the survival of the fittest as the operating mechanism for his theory. It is incredible how these two books influenced, in a very similar way, another naturalist, Alfred Russel Wallace, who developed an identical theory of evolution at about the same time. Such a coincidence belongs in a category of rare moments in the history of science. They suggest that, under the proper conditions, the birth of new ideas becomes inevitable, and that if Darwin and Wallace had not done so, someone else would have developed the theory of evolution by natural selection. We recognize similar coincidences in the discovery of oxygen by Antoine Lavoisier and Joseph Priestley and the invention of calculus by Isaac Newton and Gottfried Leibnitz. Sometimes, coincidental revolutions run across disciplines. While Albert Einstein was challenging Newtonian space and time with mathematical equations in his theory of relativity, Pablo Picasso was doing the same through the new art form known as cubism. Leonard Shlain, the author ofArt and Physics, calls this phenomenon of coincidental parallel discoveries and revolutions zeitgeist, a German term translated as the spirit of the times.
It can also be argued that Darwin and Wallace succeeded because they were able to venture outside biology. They discovered in the writings of a geologist and a political economist vital clues to their new theories. Such interdisciplinary scholarship is very much desired in today's world of science that is fragmented into so many narrow specialties, each well-focused but also dangerously disconnected from the others. I believe that the world of science would benefit if we had more scientists with the interdisciplinary mind-set of Darwin and Wallace, whose thinking "outside the box" produced one of the most important theories of science. We should encourage such thinking and integrate it into the education of all, especially the scientists. Only then may we reach the maximum creative potential of which we are capable.
Besides the survival of the fittest, Darwin speaks of another fundamental principle of nature, that of Natura non facit saltum (i.e., Nature does nothing in jumps). This is how Darwin refers to it in the recapitulation (concluding) chapter in On the Origin of Species:
"As natural selection acts solely by accumulating slight, successive, favorable variations, it can produce no great or sudden modifications; it can act only by short and slow steps . …