Intro to Cooperation Theory: We're Human Because We Teach

In a series of previous posts, I presented an annotated list of readings for people interested in understanding the multidisciplinary study of human cooperation. In my 2005 TED talk, I called for the organization of such a study. Now, 13 years later, I'm excited to see the emergence of theories based on research that has been progressing in a number of fields. Most importantly, one of the key scientists in the study of cultural evolution (cited in my reading list), Joseph Henrich, now at Harvard, has published a book that pulls it all together in a theory of gene-culture coevolution: The Secret of Our Success. The book is full of citations of research to back up the theory championed by Henrich and embraced by many: Our ability as a population (as opposed to just our abilities as individuals with big brains) to learn from each other not only drove the emergence of culture (language, norms, rituals, tools, etc -- everything we aren't born with, but end up inventing and adopting into group collections of useful knowledge), but also drove our genetic evolution toward the production of ever more capable cultural learners. 

This brief abstract on the Harvard University Press site (Henrich is now at Harvard) describes the book's thesis, which is elaborated with firm logic and language that is clearly understandable by non-specialist readers:

In the natural world,  humans are unique in using fancy technologies, sophisticated languages,  and complex institutions. These cultural products have permitted us to  expand across the globe, and thrive in nearly every terrestrial  environment. How is it that our species manages all this and more, but  other species cannot?  

Drawing  insights from lost European Explorers, clever chimpanzees,  hunter-gatherers, cultural neuroscience, ancient bones and the human  genome, Henrich shows that it’s not our general intelligence, innate  brain power, or specialized mental abilities that explain our success.  Instead, it’s our collective brains, which arise from a combination of  our ability to learn selectively from each and our sociality. Our  collective brains, which often operate outside of any individual’s  conscious awareness, gradually produce increasingly complex, nuanced and  subtle technological, linguistic and social products over generations.    

Tracking  this back into the mist of our evolutionary past, and to the remote  corners of the globe, Henrich shows how this non-genetic system of  cultural inheritance has long driven human genetic evolution. By  producing fire, cooking, water containers, tracking know-how, plant  knowledge, words, hunting strategies and projectiles, culture-driven  genetic evolution expanded our brains, shaped our anatomy and  physiology, and influenced our psychology, making us into the world’s  only living cultural species. Only by understanding cultural evolution,  can we understand human genetic evolution.  

The September, 2018 edition of Scientific American broadly expands on "the science of being human." In an introductory article by Kevin Laland (not firewalled), "How We Became A Different Kind of Animal: An Evolved Uniqueness," the author proposes that while other animals can learn socially by imitation, homo Sapiens are the only ones that have perfected teaching. We are human because we teach -- and have developed tools and methods for preserving and disseminating what we learn:

The emerging consensus is that humanity’s accomplishments derive from an  ability to acquire knowledge and skills from other people. Individuals  then build iteratively on that reservoir of pooled knowledge over long  periods. This communal store of experience enables creation of ever more  efficient and diverse solutions to life’s challenges. It was not our  large brains, intelligence or language that gave us culture but rather  our culture that gave us large brains, intelligence and language. For  our species and perhaps a small number of other species, too, culture  transformed the evolutionary process.

My mother was a teacher. I taught college students for ten years. I've always felt that teaching is one of the highest callings. Read the texts I've mentioned to understand exactly how teaching is what made us human and continues to shape both our culture and our genes.