The remains of all plants and classes of animals, whose structure permitted it, have been preserved in great abundance; and, although the distinction of species not unfrequently confronts us with unsurmountable obstacles, a knowledge of them must lead to important results; at least, if we admit that the various forms have been evolved from a primitive model, and that the species have arisen from an original generic form. (“Observations on the Nature and Importance of Geology”)
Robert Jameson, eminent mineralogist, geologist, and natural historian, was Regius Professor of Natural History at the University of Edinburgh and an early evolutionist. He taught Charles Darwin during his days as a medical student at the University of Edinburgh, and was editor of the Edinburgh New Philosophical Journal. Glimpses of an openness to an evolutionary worldview first appear in his System of Mineralogy (1804). Here, Jameson asks “Were all animals and plants originally created as we at present find them, or have they by degrees assumed the specific forms they now possess?” (xix-xx, System of Mineralogy, 1804; cf. 538, Jenkins, 2016).
Jameson’s evolutionary views proceeded from his geology. A disciple of Abraham Gottlob Werner, he adhered to and instructed his own students in Wernerian geology, or neptunism – the theory that Earth’s rock formations precipitated out of a gradually receding ocean that originally covered the earth. Central to a Wernerian concept of Earth history was the notion that this history was directional. As the planet itself evolved from a warmer watery mass towards present day environments. This view, in turn, was strongly reinforced by emerging early nineteenth century evidence for a gradual progression of organic life forms, or as Jameson wrote in 1808, “In respect to the nature of these remains [fossils], we may remark that those which occur in the earliest periods, belong to the lowest and most imperfect class of animals, the zoophytes…In the newer formations, we find the remains of known genera, and in the newest of all the remains of organic species, resembling those found in the present seas” (81, System of Mineralogy, 1808).
Recent scholarship (Secord 1991; Tanghe and Kestemont 2018) indicates that an important anonymously authored transmutationist paper “Observations on the Nature and Importance of Geology” (1826) in the Edinburgh New Philosophical Journal, was authored by Jameson. In this paper, Jameson asserts that the progressive nature of the fossil record supports transmutationism: “The doctrine of petrifactions, even in its imperfect condition, furnishes us with accounts that seem in favour of Mr. Lamarck’s hypothesis.” (296-7). Jameson went on to suggest that mutability of form over time, as was evident from the short-term domestication of plants and animals by humans, could account for gradual evolutionary change over much longer periods of time. “[A]re these forms as immutable as some distinguished naturalists maintain; or do not our domestic animals and our cultivated or artificial plants prove the contrary? If these, by change of situation, of climate, of nourishment, and by every other circumstance that operates on them, can change their relations, it is probable that many fossil species to which no originals can be found, may not be extinct, but have gradually passed into others.” (298).
Jameson has been primarily analyzed in light of his influence, or supposed lack thereof, on his student Charles Darwin, who later would disparage Jameson’s lectures in his Autobiography. “During my second year in Edinburgh I attended Jameson’s lectures on Geology and Zoology, but they were incredibly dull. The sole effect they produced on me was the determination never as long as I lived to read a book on Geology or in any way to study the science.” This assessment, which ignores Jameson’s transmutationist views, seems harsh. Charles Darwin was by no means the only person to study under Jameson and go on to espouse evolutionist views; others include Robert Grant, Robert Knox, Hewett Cottrell Watson, and Ami Boué. Clearly, Jameson must have been central to advancing evolutionary discussions among his Edinburgh students and colleagues in the early nineteenth century, and it is difficult to imagine that a young Charles Darwin was not in some way influenced by the association.