What scientific concept did John Dalton significantly contribute to?

John Dalton is best known for his formulation of the atomic theory in the early 19th century, which fundamentally changed our understanding of matter. His theory proposed that all matter is composed of atoms, indivisible particles that combine in specific ratios to form compounds. Dalton's atomic theory established that atoms of a given element are identical in mass and properties, and different elements have different types of atoms. This foundational idea laid the groundwork for modern chemistry, influencing how scientists understand chemical reactions and the composition of substances.

Dalton's contribution stands in contrast to the other concepts listed. The theory of relativity, primarily developed by Albert Einstein, addresses the laws of physics in relation to gravity and motion. Cell theory, established by scientists like Schleiden and Schwann, revolves around the fundamental unit of life—the cell. The theories of evolution, most notably articulated by Charles Darwin, explore the process of natural selection and the diversity of life over time. While these theories are all significant in their respective fields, Dalton’s atomic theory has a unique role in the development of chemical science as we know it today.