What is a Paleoecologist?

Paleoecology in Plain English

Rebecca Teed
Limnological Research Center
University of Minnesota

A paleoecologist is someone who studies groups of organisms that lived in the past. We look at different kinds of fossils to get information. For example, I'm studying the forests and prairies near a couple of lakes in central Illinois for the past 130,000 years or so. I'm doing this by examining the fossil pollen in successive layers of lake mud (the deepest layer being the oldest, the uppermost being the youngest). Each genus of tree and each family of non-woody plant produces a distinctive-looking type of pollen (although, in some cases, closely related genera produce pollen types too similar to tell apart). The relative numbers of each kind of plant tell me about the community around the lakes: prairie or pine and spruce forest during the ice ages, and deciduous forest and prairies during interglacials (like the present). I'm getting carbon-14 dates to tell me exactly how old critical layers are. The reason I'm looking at pollen instead of the leaves, wood, etc. is that the plants decomposed when they died, except for pollen, which is pretty durable, that fell into the lake (very little decomposition occurs within lake mud).

Pollen is one of the most commonly studied fossils, and the past 30,000 years are the most common period of study, but the first paleoecologist I ever met, Dr. Markes Johnson, studies groups of brachiopods (clam-like animals) that lived during the Silurian period. In terms of jobs, many of us are academics (researchers and teachers at colleges and universities). Some work for the government, particularly in the US Geological Survey. Many work for oil, coal, and gas companies, comparing fossil assemblages in the layers of earth that they are surveying with those that have been studied before to figure out how old the layers are and where they lie with respect to layers containing fossil fuel. Two of the most prominent paleoecologists in the US are here at the University of Minnesota: Professor Margaret Davis and Professor Herb Wright.