A History Of Life

School and University textbooks dealing with evolutionary biology and the founding principles of the theory of natural selection authored by Charles Darwin in 1859, make ample use of such concepts as variability, survival of the fittest, reproductive success, inheritance, frequency within populations. They often forget to explain, however, or altogether do not mention, an ingredient without which there is no ‘origin of species by natural selection’. This factor in evolution was perceived (albeit not definitely: Burchfield 1975, Gould 1987) during the years of Darwin’s own formation as a naturalist, himself having contributed in focusing its importance through some writings that preceded his most important work.

The discovery had been gradual, made thanks to the work of generations of naturalists and philosophers, through an often problematic process that radically changed the way in which scientists related themselves to the truths revealed by the Scriptures. The discovery for once had not come thanks to some new technical device like Galileo’s telescope ot Hooke’s microscope, the instruments required being available since remote times. Man’s own egocentricity the only impediment to use them, the finiteness of a man’s life and an incapacity to use anything but it to measure the world around us. The instruments we are dealing with are rocks and fossils and the factor of evolution that Darwin badly needed, Time.
The difficulty with which we all face the dark abyss of time, no one excluded, leads us to look with a renewed reverence at history’s most important naturalist, whose bicentennial we are celebrating in 2009. We tend to forget that the time available to 17th Century naturalists to conceive an History of the Earth was a few thousand years, a comforting measure when man’s the measure of all things. If today we have moved from this limiting vision we must thank many men and ideas that too often go unmentioned by the textbooks. Stratigraphy’s principles introduced by Steno after studying gemetric relationships of rocks in Tuscany, the fantastic visions of theoreticians like Athanasius Kircher and Thomas Burnet who first proposed an organic Theory of Earth’s History, the slowly accumulating knowledge on the vertical succession of fossils made by naturalists like John Ray and John Woodward, the dilemma of the origins faced by physics/philosophers like Newton and Liebniz, the estimate of 75,000 years that costed Buffon a condemnation, the thousands bones studied by Cuvier, the rocks and strata of Arduino, Hutton and Lyell. Episodes and thinkers that allowed Darwin, and us today, to measure the age of the earth in hundreds of millions of years. Without these foundations Charles Darwin would not have conceived a theory of evolution by natural selection.

References

Burchfield J.D. 1975 - Lord Kelvin and the Age of the Earth. University of Chicago Press, Chicago, 274 p.

Gould S.J. 1987 - The Flamingo's Smile: Reflections in Natural Histor. Norton Paperback, New York, 572 p.