At The Roots of 17th-Century Geology

At the Roots of
17th-Century Geology

Nicolaus Steno (1638-1686)
from Human Anatomy to Fossils

Nuno Castel-Branco

16 May 2023 – 5 PM (CEST)

In October 1666, Grand Duke Ferdinand II de’ Medici (1610-1670), the last patron of Galileo Galilei (1564-1642), asked Nicolaus Steno (1638-1686), the new anatomist at court, to dissect an extraordinarily large white shark caught in the Mediterranean Sea. This dissection became known for igniting Steno’s geological research, which made him known today as “the founder of modern geology.”
In short, the story goes, Steno realized during the dissection that shark’s teeth were equal to a kind of fossils often found far from the sea. This led him to argue that the Earth has a history, which can be known through a series of rules still taught today as Steno’s Principles of Stratigraphy. But the problem with associating this shark’s dissection with Steno’s research on fossils is that none of the eyewitnesses to the dissection mentioned the shark’s teeth nor anything related to fossils, including Steno.
In this talk, I show that the story was far more complex than simply observing the teeth of shark.
Instead, it also involved reading an almost-hundred-year-old manuscript about fossils that directly contradicted Steno’s research methods in anatomy. This shift, however, can only be glimpsed through a serious consideration of Steno’s anatomical career until then.
By reading Steno’s studies of the Earth in light of his anatomical writings and unpublished manuscripts, I show that Steno’s turn to the study of fossils is better understood in light of his studies of the body.
This question of how Steno shifted from anatomy to Earth history also speaks to broader themes in the history of science. How and why did different areas of knowledge intersect and relate to each other in the early modern period? What roles did the early modern life sciences, and especially anatomy, play in early modern science at large? Therefore, this talk uses the intricate details of Steno’s turn to fossils to improve the historical understanding of early modern science, including how anatomy influenced other areas of knowledge.

About the Speaker ...

Nuno Castel-Branco is a historian of science at Villa I Tatti, the Harvard University Center for Italian Renaissance Studies.

Next fall, he will start a Research Fellowship at All Souls College, Oxford University. He has an M.Sc. in Physics from the University of Lisbon and completed a PhD in the History of Science at Johns Hopkins University in May 2021. He is writing a book on the intersection of mathematics, the life sciences, and theology in the work of the seventeenth-century anatomist Nicolaus Steno. His research has been sponsored by various institutions in Europe and the United States, such as the Fulbright Foundation and the Max Planck Institute for the History of Science. Nuno has written for academic and popular audiences in journals like Renaissance Quarterly, Wall Street Journal, and Scientific American.

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