John W. Williams

Dr. John W. Williams is Professor in the Department of Geography at the University of Wisconsin–Madison, formerly directing the Center for Climatic Research. His education includes a PhD and MSc from Brown University (Geosciences) and BA from Oberlin College (Geology). Research focuses on paleoecology, paleoclimates, and vegetation responses to environmental change, with active projects in ancient environmental DNA analysis and paleoecoinformatics.

Research areas encompass:

• Novel ecosystems under climate change
• Abrupt ecological transitions
• Megaherbivore extinction impacts
• Data-model integration techniques

Recent publications demonstrate leadership in climate-vegetation dynamics, including development of the Range Mapper visualization tool and Neotoma Paleoecology Database. Research integrates field data collection, pollen analysis, and computational modeling to study ecological responses from glacial periods to anthropogenic futures. Current investigations include ancient environmental DNA applications in lake sediments to track plant community changes.

Teaching includes courses in physical geography, paleoecology, climate change science, and graduate seminars. Leads the Williams Lab mentoring graduate and undergraduate researchers, with active collaborations across ecology, climatology, and bioinformatics disciplines.