James Croll, a Scottish janitor and self-taught scholar, made significant contributions to our understanding of the Earth's climatic changes. He formulated theories about Earth's orbital mechanics that offered a scientific basis for the onset of ice ages, marking a crucial development in climatology. Despite his humble beginnings and lack of formal education, Croll's insights were groundbreaking and showcased the potential of individual curiosity and intellect to advance scientific knowledge.

In "A Short History of Nearly Everything," Bill Bryson highlights Croll’s journey as an example of how passion and self-education can lead to remarkable discoveries. Croll's work laid the foundations for later research into Earth's climate patterns, emphasizing the importance of understanding our planet's physical changes over time. His legacy is a testament to the impact of unexpected contributors to science and the critical role of observational theory in developing explanations for complex natural phenomena.