The Earliest Paleontologists

The ancient Greeks recognized that marine shells found in outcroppings around the Mediterranean Sea marked areas that had once been under water. Herodotus, the Greek historian and traveler, mentioned fossil sea-shells he had seen in Egypt and drew the conclusion that the sea had at some time covered Lower Egypt.

But other Greek thinkers left behind some mischievous ideas, such as Aristotle's teachings that there had been only a single creation. These ideas became mingled with the Church's dogma of the literal creation in six days and effectively stifled men's sense of inquiry until the 15th century.

Leonardo da Vinci (1452-1519), the great painter and architect, reasoned rightly that the presence of fossils uncovered in Lombardy indicated that northern Italy had been repeatedly inundated by the sea. However, he was one of the few free spirits of his age, an age when most men described fossils as sports of nature (lusi naturae), as seeds of life that had grown by accident in the rocks, or as the bones of unicorns, legendary giants, or sinners drowned in the Biblical Flood.

But it was in this age that fossils got their name. Georgius Agricola (1494-1555), the first professional mineralogist, used the Latin word fossilis in his great work on systematic mineralogy, De natura fossilium, published in 1546. To Agricola, fossilis meant anything dug up from the earth; later writers picked up the word from him and distilled its meaning to include only what we now call fossils.

The Renaissance brought an intellectual climate that allowed a more rational view of nature. Count George Louis Leclerc Buffon (1707-1788) recognized that the rocks of the Paris basin were the product of untold ages of erosion and deposition. He also saw that they could not be sandwiched into the estimate of the age of the earth, made from the Biblical chronology, of about 6,000 years. His contemporary, the Scottish geologist James Hutton (1726-1797), went a giant step further. While such men as Buffon were attempting to explain away the contradiction by presuming that catastrophes had hastened the changes they plainly saw, or else fancied that what the Bible spoke of as days should be read as epochs of time, Hutton boldly faced the facts. He put a solid foundation under the study of geology and of fossils with his principle of uniformitarianism — that geological forces in the past were like those operating today and that no extraordinary forces or events need be invented or conjured up to explain geological history.

Another Frenchman, Jean Baptiste Pierre Antoine de Monet, Chevalier de Lamarck (1744-1829), in his little book Hydrogeologie (1802), first definitely restricted the word "fossil" to "the still-recognizable remains of organized bodies." Elsewhere he made the first major study of invertebrate paleontology and advanced the theory that all life had developed progressively from rudimentary forms to its culmination in man—a theory of evolution.

At the same time, Baron Georges Chretien Leopold Dagobert Cuvier (1769-1832) was laying the foundations of vertebrate paleontology. He had also discovered that a series of deposits made up the Paris basin and that each one had characteristic fossils by which it could be recognized wherever it appeared. This principle was confirmed by the independent discoveries made across the Channel by William Smith (17691839,) who is usually described as the father of English geology. Smith, a surveyor, examined the fossils found as his men dug canals, noted that he could use them as indicators of the type of ground to be expected elsewhere, and from this experience developed toward the end of the eighteenth century his fundamental principle of correlation—that like rock strata have like fossils by which the strata can be recognized wherever they are found.

With the work of such men, with the summing up of their discoveries by Sir Charles Lyell in his Principles of Geology, and with acceptance of Darwin's theory of evolution, men finally began to comprehend the meaning of fossils.

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