Ecosystems and the Biosphere as Complex Adaptive Systems: Scaling, Collective Phenomena, and Governance
Simon A. Levin
- James S. McDonnell Distinguished University Professor Ecology and Evolutionary Biology, Princeton University
Sustainability of the biosphere is the ultimate global challenge. Ecological and economic systems are alike in that individual agents compete for limited resources, evolve their behaviors in response to interactions with others, and form exploitative as well as cooperative interactions as a result. In these complex adaptive systems, macroscopic properties like the flow patterns of resources such as nutrients and capital emerge from large numbers of microscopic interactions, and feed back to affect individual behaviors. I will explore some common features of these systems, especially as they involve the evolution of cooperation in dealing with public goods, common pool resources and collective movement, with implications for governance of the Commons. I will describe examples from bacteria and slime molds to vertebrate groups to insurance arrangements in human societies and international agreements on environmental issues. These present mathematical challenges including scaling from the microscopic to the macroscopic, the emergence of pattern, critical transitions and conflicts between the interests of individuals and the good of collectives.
4:30 p.m. Arizona Time