April Lecture - Pollen as a Window into the Past

posted Mar 22, 2012, 8:46 AM by Marty Nielsen
Pollen as a Window into the Past
How Ecologists Use Pollen to Reconstruct Past Vegetation
Thursday, April 19 at 7:30 pm
Green Spring Gardens Park
Speaker:  Dr. Emily W. B. (Russell) Southgate
While we all know that living pollen is very cool, most of you may not know that fossil pollen can be used to help reconstruct past environments, back thousands, and even millions, of years.  The chemical that makes up the outer layer of a pollen grain is very resistant to decay, as long as it is in an anaerobic environment, like the bottom of a lake.
Pollen grains also have a tremendous variety of sculpturing which can be used to identify them to family, genus, or even species.  Dr. Southgate will provide an overview of pollen production, illustrate the variety of kinds of pollen and how to distinguish them, and describe the structure of pollen grains and their apertures.   She will talk about the difference between wind- and insect- pollinated plants, in terms of the amount of pollen produced and how it gets where it needs to.
Dr. Southgate will then discuss how paleoecologists use the unique characteristics of pollen preserved in sediments as a window on the past.  You will see pictures of pollen from a variety of local plants, with key characters that we use to tell them apart.  Dr. Southgate will then walk us through the steps from the plants that produce pollen to an interpretation of changing vegetation and climate over the last few thousand years in the eastern United States.
VNPS programs are free and open to the public.  No reservations are necessary.