Humans emit more gases in a year than volcanoes, reform landscapes for agriculture, mining, energy and cities and generate mountains of waste. Humans have become shapers of Earth on a scale similar to or even exceeding natural processes, and in some cases, even beyond what extreme natural processes are capable of in short much shorter time scales. The unit will explore the questions such as: Are we pushing our atmosphere and ocean to the extremes, and thereby limiting the viability of humans and other living organisms? Are we, by reshaping Earth according to human need, initiating the sixth mass extinction? Does it matter, and what should we do, if we are? Can society's existing systems and governance structures deal with these events or do they need to be changed? Can we engineer solutions in order to redesign our planet in ways to promote a future we can and want to live in? And even if we are capable of 'geoengineering,' is there a will to apply it and is it wise to pursue it? What values are relevant to answering these questions and how are decisions to be made in the face of competing values? This unit will explore the science, governance and values relevant to the issue of mass extinction and human earth shaping.