Name the scientist who proposed the theory of natural selection.

Charles Robert Darwin, along with Alfred Russel Wallace, proposed the theory of natural selection in the 19th century. Darwin's work, primarily outlined in his book "On the Origin of Species" (published in 1859), explained how species evolve over time through a process where individuals with advantageous traits are more likely to survive and reproduce. This mechanism, known as natural selection, drives the adaptation of organisms to their environments. Wallace independently developed a similar theory, which he presented alongside Darwin in 1858. Their combined contributions laid the foundation for modern evolutionary biology, emphasizing that variations within populations, inherited traits, and environmental pressures shape the diversity of life.