Answer: Alfred Russel Wallace

Although the name Charles Darwin and the theory of evolution through natural selection are inexorably intertwined at this point in history, Darwin was not the sole progenitor of the theory. Like many breakthroughs in science over the centuries, both Darwin and a fellow scientist were building on the same knowledge at the same time and moving towards the same conclusion.

Concurrently, both Darwin and another naturalist, Alfred Russel Wallace, independently conceived the theory of evolution through natural selection and Wallace’s paper on the subject was jointly published with some of Darwin’s writings on the matter in 1858. The publication actually prompted Darwin to hurry his work along and publish his iconic work On the Origin of Species which, ultimately, led to Darwin becoming the recognized face of evolutionary science.

That slight of acknowledgement and achievement aside, Wallace was a renowned scientist in his own right. Not only did he come up with evolution through natural selection right alongside Darwin, he was also the 19th century’s leading expert on the geographical distribution of animal species and is sometimes cited as the “father of biogeography”. His numerous latter-19th century writings on the matter of evolution helped to establish and validate the fledgling science.