Sources
Social Evolution | Heather Long and Kelly Chakov (1996)www. anthropology.ua.edu/cultures/cultures.php?culture=Social%20Evolutionism
A Brief History of Cultural Evolution: Stages, Agents, and Tinkering | Jonathan Haas (2016)
https://www.santafe.edu/research/results/working-papers/a-brief-history-of-cultural-evolution-stages-agent
The Cultural Evolution of Humans (With its stages) | P Tiwari
http://www.geographynotes.com/human-geography/the-cultural-evolution-of-humans-with-its-stages/1000
Social Identity Theory | Saul Mcleod (2008)
https://www.simplypsychology.org/social-identity-theory.html
Cultural Evolution | Alex Mesoudi (2012)
http://www.oxfordbibliographies.com/view/document/obo-9780199766567/obo-9780199766567-0038.xml
Man and Society | A. Spirkin
https://www.marxists.org/reference/archive/spirkin/works/dialectical-materialism/ch05-s04.html
FUTURE HUMANS: Four Ways We May, or May Not, Evolve | James Owen (2009)
http://news.nationalgeographic.com/news/2009/11/091124-origin-of-species-150-darwin-human-evolution.html