Final answer:
The theory of neo evolutionism emerged from the contributions of multiple scholars, with Charles Darwin and Alfred Russel Wallace foundational in biological evolution. Theories in social evolution were later influenced by Leslie White and Julian Steward. Herbert Spencer and William Graham Sumner applied evolutionary concepts to society and economics.
Step-by-step explanation:
The theory of neo evolutionism was not developed by a single individual but rather emerged from the works of several scholars advancing upon the concept of evolution. In biology, Charles Darwin and Alfred Russel Wallace are credited with the formulation of the theory of evolution by natural selection. In the social sciences, concepts similar to neo evolutionism were later advanced by thinkers such as Leslie White and Julian Steward, who are often associated with the development of cultural evolution theories that drew upon and extended biological evolutionary theory to explain social progress.
Alfred Russel Wallace is often mentioned alongside Darwin for independently conceiving the theory of evolution by natural selection. The integration of Darwin and Wallace's ideas with subsequent genetic findings led to what is known today as the modern synthesis, further advancing the understanding of evolution.
Later, Herbert Spencer introduced the term 'survival of the fittest' while William Graham Sumner became a proponent of social Darwinism, applying evolutionary concepts to social and economic realms, although these ideas were later criticized and fell into disrepute.