About the Skittle Core Lab
"Why do scientists take sediment cores?" A fifth-grade student asked Dr. Sam Bowser, a marine biologist, this question, and this lab was designed to help students explore the answer.
Dr. Bowser has conducted research in Explorers Cove, Antarctica, since 1984. Dr. Bowser's team dives beneath the Antarctic ice to study foraminifera. Forams are single-celled protists that live in all the oceans of the world. Foraminifera lived long before the dinosaurs roamed the Earth, yet they still live today on the bottom of the seafloor (benthic), in the water column (planktic), or attached to rocks or other hard substrates.
These microorganisms are significant because of their abundance, diversity, and worldwide distribution. They are sensitive to their environment, which makes them "watchdogs on the environment", or a lens on the past and the present. They are climate change detectors. Forams must live in a world conducive to their survival, so they depend on many abiotic and biotic factors. Foraminifera rely on specific parameters to meet their needs. Abiotic (non-living) factors, such as water temperature, salinity, pH, sunlight, oxygen, pollution, rocks, glacier scouring, sediment, and even the size of the sand grains may adversely affect the life of a foram. Living organisms, such as plants, animals, and other protists are biotic factors that provide nutrients and shelter for a thriving community, or hasten the demise of others. Both, abiotic and biotic factors, could affect the foram population in an area.
Since scientists can't count every foram in the ocean, they must sample the population. By doing a simulated activity with skittle-laden brownies, the students "do the math" to extrapolate the data to project the "foraminiferal population" in areas the size of a school's gym, which is roughly the size that Dr. Bowser samples to make comparisons from year to year within the region of New Harbor, near the Ross Ice Shelf in Antarctica.
This class exercise was developed in cooperation with a team of dedicated teachers. Tina King was a vital element of the design team, and Amy Clapp, Danielle Coletta, Karleen Hayden and Andrea Inserra beta-tested the exercise with their own classes. Bob King played a primary role in developing the math skills and data sheets for the exercise.
Underwater photography and coring courtesy of Henry Kaiser, Steve Clabeuesch, and Neal Pollock. Video created by Henry Kaiser. Web design by Andrea Habura.