Da Vinci and Geology, Fossils and the Bible

Leonardo da Vinci understood geology based on physical evidence he found. His studies of rocks, fossils, and river erosion led him to the conclusion that the world is far older than stated in the book of Genesis, and he argued that marine fossils found in the mountains were the result of falling sea levels, not the Great Flood.

He wrote:

And a little beyond the sandstone conglomerate, a tufa has been formed, where it turned towards Castel Florentino; farther on, the mud was deposited in which the shells lived, and which rose in layers according to the levels at which the turbid Arno flowed into that sea. And from time to time the bottom of the sea was raised, depositing these shells in layers, as may be seen in the cutting at Colle Gonzoli, laid open by the Arno which is wearing away the base of it; in which cutting the said layers of shells are very plainly to be seen in clay of a bluish colour, and various marine objects are found there.

A page of Leonardo's Paris Manuscript I is covered in sketches of marine fossils.

Among them is a honeycomb-like array of hexagons that palaeontologists think might constitute the first recorded observation of an enigmatic trace fossil called Paleodictyon.




He recognized fossils as petrified remains of former living organisms and even applied paleoecological principles to reconstruct the deposition of sedimentary rocks. Of course, he never published his notebooks and his theories were not well known during and for many years after his death.

Later, Nicolas Steno (1638-1686), with his stratigraphic principles, Robert Hooke (1635-1703), with his paleontological interpretation of fossils, and finally James Hutton (1726-1797), with his earth-theory, would make discoveries and theories that would have an impact on scientific thinking.