Variation and natural selection would also afford a key to a multitude of geological facts otherwise wholly unaccounted for, as, for example, why the… - Charles Lyell

Fabio Colonna deserves to be distinguished; for, although he gave way to the dogma that all fossil remains were to be referred to the Noachian deluge, he resisted the absurd theory of Stelluti, who taught that fossil wood and ammonites were mere clay, altered into such forms by sulfurous waters and subterranean heat; and he pointed out the different states of shells buried in the strata, distinguishing between, first, the mere mould or impression; secondly, the cast or nucleus; and thirdly, the remains of the shell itself. He had also the merit of being the first to point out, that some of the fossils had belonged to marine, and some to terrestrial testacea.

Falloppio of Padua conceived that petrified shells had been generated by fermentation in the spots where they were found, or that they had in some cases acquired their form from 'the tumultuous movements of terrestrial exhalations.' Although a celebrated professor of anatomy, he taught that certain tusks of elephants dug up in his time at Puglia were mere earthy concretions, and, consistently with these principles, he even went so far as to consider it not improbable, that the vases of Monte Testaceo at Rome were natural impressions stamped in the soil.

I endeavoured to sketch out (and it was, I believe, the first systematic attempt to accomplish such a task) the laws which govern the extinction of species, with a view of showing that the slow, but ceaseless variations, now in progress in physical geography, together with the migration of plants and animals into new regions, must, in the course of ages, give rise to the occasional loss of some of them, and eventually cause an entire fauna and flora to die out; also, that we must infer, from geological data, that the places thus left vacant from time to time, are filled up without delay by new forms, adapted to new conditions, sometimes by immigration from adjoining provinces, sometimes by new creations. Among the many causes of extinction enumerated by me, were the power of hostile species, diminution of food, mutations in climate, the conversion of land into sea, and of sea into land, &c.