The British naturalist known for his contributions to ecology is Charles Darwin. Renowned for his theory of evolution through natural selection, Darwin's groundbreaking work fundamentally changed the understanding of biological science. His seminal book, "On the Origin of Species," published in 1859, laid the foundation for modern evolutionary biology. Darwin's extensive research on species during his voyage on the HMS Beagle provided vital insights into biodiversity and ecological interactions. His ideas have had a profound and lasting impact on the scientific community and our understanding of the natural world.