Trimble Lecture with Jim Fleming, PhD
"Cosmic Connections: James Croll’s influence on Charles Lyell and Charles Darwin"
This paper examines the influence of the Scotsman James Croll (1821-1890) on his contemporaries, Charles Lyell and Charles Darwin. Working at the nexus of astronomy, geology, and natural philosophy, Croll developed an astronomical theory of ice ages in which variations in Earth’s orbit orbital triggered feedbacks leading to complex changes in climate and the distribution of plant and animal life. Croll was an autodidact deeply involved in metaphysical thinking and an early proponent of what came to be called “cosmic physics.” He referred to climate change as the most important problem in terrestrial physics, and the one which will ultimately prove the most far reaching in its consequences. It is widely known that Lyell’s geology helped frame Darwin’s theory of evolution, but Croll’s significant influences on both Lyell and Darwin have yet to be explored.