Many of the things that make humans unique are not hard-wired in our genes, but are
shaped by the behaviour and norms of those around us – these are inherently cultural
phenomena that require a cultural explanation.
Since Darwin, it has been recognised that human cultures and languages evolve in ways that parallel the
evolution of species. These parallels of process mean that methods and thinking from biology can be
used to shed light on the evolution of language and culture. My research uses these tools to understand
how human culture evolves and the importance of culture for the evolution of our species. This includes
work on the evolution of language, religion, cooperation and the human expansion from Africa.
Evolution of cooperation and prosocial behaviour
Understanding human cooperation is critical both for unravelling our evolutionary past and for tackling the challenges of our future. The long-term survival of our species rests on our ability to cooperate to sustainably manage common resources like our fisheries, forests, water and atmosphere. But how do we achieve this? What factors promote cooperative behaviour? And how did human cooperation evolve? Increasingly, researchers are looking for the answers to these questions not in our genes, but in our culture. Field and lab-based studies reveal substantial differences in levels of cooperation across cultures and point to the importance of cultural norms and institutions for promoting cooperation in large groups.
In Auckland, we are investigating how prosocial environmental beliefs and behaviours vary across social networks. At field sites across the Pacific, we are using experimental and ethnographic research methods to investigate the cultural evolution of human cooperation. This research is currently funded by a Rutherford Discovery Fellowship from the Royal Society of New Zealand.
Evolution of Religion
Religious adherence often entails great sacrifice of time and resources, and sometimes even of life. On the surface, many religious beliefs and practices thus seem highly maladaptive. However, there is increasing interest in the possibility that religions provide benefits to groups by promoting cohesion and cooperation. For example, religious rituals can facilitate bonding between group members and provide a costly signal of group commitment. Likewise, belief in a supernatural agent who will punish moral transgressions may help promote prosocial behaviour by providing a “supernatural police force”. Our lab’s research in this area seeks to characterise patterns of recurrence and variation in religious beliefs and practices in cultures around the world, to explore the link between features of these beliefs and practices and large-scale cooperation, and to explain what it is about the human mind that makes certain types of religious beliefs and practices particularly appealing. This includes lab-based studies, online experiments and field research on Tanna Island in Vanuatu. The research is funded as part of the Cultural Evolution of Religion Consortium (CERC) hosted at the University of British Colombia, the Ritual, Community and Conflict project hosted at the University of Oxford and a Templeton Foundation project hosted at the University of Auckland.
Evolution of language
Language is fossil poetry. As the limestone of the continent consists of infinite masses of the shells of animalcules, so language is made up of images, or tropes, which now, in their secondary use, have long ceased to remind us of their poetic origin.
– Ralph Waldo Emerson – The Poet from Essays: Second Series (1844)
Languages, like species, evolve via a process of descent with modification. Biologists can draw inferences about species’ ancestry and the forces affecting biological evolution by analysing genetic diversity using stochastic models of evolution. In a similar way, we use stochastic models of the process of language evolution together with data on linguistic diversity to infer ancestral relationships between languages and answer questions about human history and the process of cultural evolution. Click here to find out more about how we applied this approach to investigate the origin of the Indo-European language family. Click here to find out more about our North American English Dialects Project with Dr Claire Bowern at Yale.
This research is currently funded by a Marsden Grant from the Royal Society of New Zealand – “Tongues, trees and Bayesian inference”.
Human population genetics
Human genetic diversity carries a legacy of our population history. By comparing sequence data from people living in the world today, we can draw inferences about when and where humans originated and how populations grew as we spread out across the globe. We use human genetic variation together with Bayesian inference of phylogeny to investigate past human population dynamics and reconstruct a picture of the human colonization of the globe.
In 2007, I co-edited a book with Dr Niki Harré, from the University of Auckland, called “Carbon Neutral by 2020: How New Zealanders can tackle climate change”. This project brings together New Zealand-based experts from a range of disciplines who offer practical solutions to the challenge of reducing carbon emissions and present a vision of a carbon neutral New Zealand in 2020. Click here for a promotional flyer.