Phoebe Cohen

Assistant Professor of Geosciences
Williams College
203 Clark Hall
947 Main Street
Williamstown MA 01267
Phoebe.A.Cohen@williams.edu
Lab website
Death Valley Portraits-1

Research Interests

My work focuses on the interactions between Earth and life in deep time. Specifically, I seek to better understand eukaryotic and animal evolution in the Proterozoic (2500 million years ago — 543 million years ago). Changing biological and environmental factors during this period of Earth history set the stage for the radiation of animals and the emergence of Phanerozoic ecosystems and diversity. However, biological events in the Proterozoic are often obscured due to gaps in the fossil record, poor age constraints, and uncertainty surrounding the taxonomic affinity of fossils. Through my research, I seek to overcome these problems by integrating data from the fossil record, the rock record, and modern phylogenetics and physiology. I am also interested in interpreting the Phanerozoic microfossil record in light of work on modern eukaryotes.

I use a number of methods to examine the Precambrian history of life. These include: 1) finding and describing new fossils in Precambrian strata, 2) using analytical tools to examine those fossils in order to determine taxonomic affinity, taphonomy, functional morphology, and paleoecology, 3) using modern analogs to determine phylogenetic relationships and physiology of early eukaryotes and animals, and 4) combining multiple sources of data to create a timeline of biotic and abiotic events in the Precambrian. Data from such investigations provide a unique perspective on the events in this time period, and together present a cohesive framework for examining eukaryotic and animal evolution through the Proterozoic and into the Phanerozoic Eon.