Everyone knows that Darwin was a biologist, and in many ways he was the first prominent modern biologist. Though Darwin scholars know this, many people do not realize that he was also a geologist. Really, he was mainly a geologist on the day he stepped foot on The Beagle for his famous five year tour. This is especially true if we count his work on coral reefs as a geological study, even though coral reefs are a biological phenomenon. After all, the standing model for coral reef formation at the time came from the field of Geology.
To exemplify this, I've put together a list of several of Darwin's print publications with their publication dates:
- 1839 Journal of researches into the geology and natural history of the various countries visited by H.M.S. Beagle. Known to us as "The Voyage of the Beagle"
- 1842 The structure and distribution of coral reefs.
- 1844 Geological observations on the volcanic islands visited during the voyage of H.M.S. Beagle
- 1846 Geological observations on South America.
- 1846 "Note on sandstone and query on coral reefs" contribution to a book
- 1851. Geology (book section)
- 1851 A monograph of the sub-class Cirripedia, with figures of all the species. The Lepadidæ; or, pedunculated cirripedes
- 1851 A monograph on the fossil Lepadidae, or, pedunculated cirripedes of Great Britain.
- 1854. The Balanidae, (or sessile cirripedes); the Verrucidae.
- 1855 A monograph on the fossil Balanidae and Verrucidae of Great Britain
- 1857 Geologia (book section)
- 1859 On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life
There are other items on his publication list, including small contributions to various books, and some letters, not listed here. The nature of publications in the mid 19th century was different from what we see today, so it is hard to define what is a publication and what is not. For the present purposes I've excluded Gould's monographs on birds, which make very heavy use of Darwin's field descriptions. These were published between 1838 and 1841. I've also excluded two book chapters (in books written by others) on methods.
Some of these works are clearly about geology, others clearly about biology. Assume that the first item on this list, "The Voyage" is about half geology and half biology. This assumption underestimates the amount of geology and divides a lot of stuff that is not in either of the two categories, but a rough estimate is suitable. This list ends with the first edition of Darwin's "On the Origin of Species..." in 1859. The following graph shows the cumulative word count of writings (given the above caveats and adjustments) for geology vs. biology. I've added a rough estimate of Darwin's contributions to Gould's bird monographs.
Notice that geology dominates in Darwin's writings up until the origin. Thereafter, most of Darwin's published works are biological and not geological (not counting reprinted or new editions of geological or biological publications) so over time the Biology line would overtake the geology line. But up to this point, Geology dominates.
The leftmost part of this graph, where biology seems to surpass geology, I'm sure, would reverse if I spent more time classifying the verbiage in The Voyage.
Darwin may well have become the world's greatest biologist, but he started out as a notable geologist and made contributions to that field that lasted. Had he not written The Orign or any later biological work, and never published anything significant on Evolution, Darwin would today be a somewhat obscure but important geologist known to those who study South American geology, volcanic islands, and coral reefs.
I've been visiting Tasmania for almost 4 months, going back home to the flat, boring bit in the middle of North America in a couple of weeks. I've been trying to get out and explore this island as much as I can. Charles Darwin visited Tasmania during the Voyage of the Beagle; according to a book I'm halfway through, "In Tasmania" by Nicholas Shakespeare, Darwin climbed Mount Wellington during his visit to Hobart, while Captain Fitzgerald discovered an error in Hobart's time-keeping. Apparently Darwin described dozens of species of arthropods (mostly insects, but I think many spiders, etc. as well) in Tasmania, and I suspect (though I haven't read widely or deeply enough) the geology of this place contributed to his thoughts on geological processes.
Anyway, knowing good ol' Chuck was here before me has been a wonderful thought to keep in the back of my mind, and the combination of stunning geology and intriguing biology here makes me think that Charles wasn't too much in the habit of dividing his attention strictly between the two realms. If you spot a new-to-science insect sitting on a rocky outcrop of Dolerite, a mineral that dominates Tasmania (and almost nowhere else) and is on the surface as a result of some very impressive volcanic activity, do you reach for your killing jar or for your rock hammer? Both, of course!
I did not know that Charles Darwin was a geologist. Of course, when you are the author of a book of the magnitude that Origin of Species is, it is clear why his geological legacy takes a backseat. Interestingly, it should be noted that geological forces shape the biology that can live in that area, and biological forces play a huge role in soil interactions, physical weathering of rock, and other surficial geology. The point is, both are inextricably linked-as is ALL science- to one another. Thanks, Charles for not only your contributions to biology, but geology as well. I find it inspiring when scientists take a multidisciplinary approach and step out of the box a bit in order to come to some conclusion. Well done!
Also, dolerite is a rock, not a mineral. It's composition is similar to plutonic gabbro , and volcanic basalt. Here is more information; http://www.scran.ac.uk/packs/exhibitions/learning_materials/webs/43/dol…
Thanks Sam, I didn't know the difference between "rock" and "mineral". I consider myself a biologist, and as a student in a Soil Science department, one of those, too. Which means I often get asked about Geology; despite my interest, I'm not the right person to ask about such things!
Regardless, dolerite forms some really interesting-looking formations, my mind got blown on a recent visit to Cape Raoul.
Well said that Darwin was firstly a geologist, perhaps mention should also be made of the pamphlet, `Extracts from letters addressed to Professor Henslow by C. Darwin, Esq’, dated 1 December 1835, privately printed for distribution to members of the Cambridge Philosophical Society. While they also cover other topics, these letters were read, without Darwin's knowledge, at a meeting of the Cambridge Philosophical Society, 16 November 1835, with the president, Rev. Dr William Clark, in the chair. The minutes record:
"Extracts were read of letters from C. Darwin Esq. of Christ's College containing accounts of the Geology of certain parts of the Andes and S. America. Observations by Prof. Sedgwick and Henslow."
They were significant in promoting Darwin's reputation as a geologist almost a year before the Beagle returned to England, and influenced his father's decision to support his career as a naturalist.
However, from the outset Darwin was a naturalist in a more general sense and I think it's not quite right to say that he was mainly a geologist on the day he stepped foot on The Beagle. To quickly review the sporadic development of his interest in geology, after collecting pebbles as a child he went to Edinburgh University and heard both sides of the current debate between Huttonian and Wernerian geology. His recollection was that he "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."
His interests in natural history were focussed on marine invertebrates, beetle collecting and then botany with Henslow, as well as a passion for bird shooting. It was only in 1831 during last terms at Cambridge that Darwin read Humboldt's travels, and became determined to visit Teneriffe. Henslow, who himself had some background in geology, persuaded Darwin to study the subject. Darwin joined Adam Sedgwick's geology course, then travelled with him in the summer for a fortnight, in order to map strata in Wales.
Darwin returned home from this trip on 29 August to find Henslow's letter about captain FitzRoy's offer of a place for a naturalist on the Beagle, "qualified for collecting, observing, & noting any thing worthy to be noted in Natural History", more as a gentleman companion than a mere collector. Don't think anything was recorded of it at this time, but in 1839 when writing up accounts of both voyages, FitzRoy recalled examining a rock sample with "regret that no person in the vessel was skilled in mineralogy, or at all acquainted with geology", and "inwardly resolving, that if ever I left England again on a similar expedition, I would endeavour to carry out a person qualified to examine the land."
At some early point, Fitzroy gave Darwin the first volume of Lyell's 'Principles of Geology', and on their first stop ashore at St. Jago Darwin put this to good use, starting work geologising on 17 January 1832. From his autobiography, "It then first dawned on me that I might perhaps write a book on the geology of the various countries visited, and this made me thrill with delight."
Darwin is, of course, an industry, but an industry which the molecular biological revolution and the Cambrian explosion have destined for the rust-belt. Those of a mind open to what Darwin might say 150 years later about his theory and social impact are invited to peruse "I, Charles Darwin: Being the Journal of His Visitation to Earth in the Year 2009."