Adam: Studying past climates through (micro) fossils (Part I)

Last time on this blog, I spoke primarily about my undergraduate research here in Bodega. Now I now look to discuss the research I have been working on to assist Dr. Kate Davis. Her interests lie in paleobiology, the study of the past through fossils, with a focus on microorganisms.

This time around, the organisms of interest are foraminifera. Foraminifera, or forams, are microorganisms composed of cytoplasm enveloped in a shell. Because of their sensitivity to their surrounding environmental conditions, forams are often the subject of paleooceanographic studies (understanding past marine environments). In this research, we are hoping to be able to better understand the origins of the chemical composition of foraminifera shells in relation to environmental conditions.

Foraminifera: exhibiting a red-brown color and an empty final chamber (Credit: Catherine Davis)

Foraminifera: exhibiting a red-brown color and an empty final chamber (Credit: Catherine Davis)

The study began with obtaining a large number of forams. To accomplish this, plankton tows were taken both in and around Bodega Bay waters. A plankton tow is a method of capturing plankton, forams, and other microorganisms. When the tows returned to us in the lab, we began searching! The process consisted of swirling the whole sample in a large bowl to get the denser materials, like forams, to fall into the center; a small sample was then taken from the center and put in a sample dish under a microscope; forams that were found in the sample were transferred into a separate water dish. Each individual foram - the size of a sand grain - was then transferred into their own water filled bottles and then maintained at a constant temperature.

We then made observations of the foraminifera in the bottles - things like color, rhizopodia density, number of adult chambers, the fullness of the final chamber, and length of the short and long sides of the shell. Rhizopodia are the extension of the foram’s cytoplasm outside of its shell. Good health was primarily determined by the foram having a pink or red-brown color and a high rhizopodia density. Observations and photographs were taken daily to record progress (see a cool video here). 

Check out part II of my story to hear more about this experiment!

~Adam Rueckert is a recent graduate of UC Davis, with a B.S. in Marine & Coastal Science.


For more information, check out previous posts by Hill lab students: