Darwin Day

Talk abstract: Humans are the only living members of a diverse branch of ancient relatives. We have not been alone for long. Many extinct populations accompanied our species through most of our evolution. Recent work in many parts of the world has shown the remarkable behavioral complexity of some of these ancient relatives. This lecture will outline many of these discoveries, with special focus on the exploration work by Professor Hawks and coworkers in South Africa. Many of these discoveries show that brain size is not the powerful factor in behavioral complexity that scientists once thought, posing new and exciting problems within the broader landscape of neuroscience and evolution. In honor of Darwin Day celebration, the talk will recognize the ideas and contributions of Darwin and Alfred Russel Wallace toward understanding the behavioral and cognitive aspects of our origins.

Talk abstract: How come mammalian evolution is a story of the largest animals getting ever larger, and the human brain becoming the one with the most neurons? Traditional accounts abiding by Darwin’s legacy of “improvement through natural selection” have sought to explain the advantages of being bigger or having lots of neurons – but they fail to explain why the tiny mammals never went away. I will present an alternative account of mammalian evolution, and human evolution in particular, in a Whatever Works framework that focuses on the interplay between the physical constraints of energy and time on the one hand, and the opportunities afforded by biological variation on the other. In this framework, the evolution of human numbers of cortical neurons became possible once cooking technologies freed our ancestors from energetic constraints – and afforded them more time to live, which in turn allows for enhanced social interactions, larger social groups, more technology, and progress through cultural transmission.