Mystery Meat

In this lesson students follow the steps of scientists Steve Palumbi (Stanford University) and Scott Baker (University of Oregon), who used DNA data (“Barcoding”) to reveal the species identifications of kujira (whale meat) from foreign markets. Their study used DNA data to identify unknown organisms in order to investigate whether whales are being illegally hunted and sold as meat. By going through the lesson, students practice various aspects of the process of science by asking scientific questions, collecting and analyzing data, comparing their results with those of the real researchers, and finally determining possible next steps.

Students begin by reading some brief background information on ctaceans and International Whaling Commission (IWC) laws protecting them, and on DNA barcoding techniques. They come up with their own investigation questions(s) and alternative hypotheses about what the meat they test could reveal. Students then use a set of web pages to examine several DNA sequences from meat samples taken from the market. These web pages are set up to mirror the exact process that researchers use when conducting this type of study. When students “submit” their unknown barcodes two outputs are produced: 1) a phylogenetic tree showing how close the unknown barcode clusters with barcodes taken from known species, and 2) a data table showing percent similarity to known species. Students record their results, then use these these results as evidence to test their hypotheses about the hunting status of each organism revealed. Finally, students compare what they found with Baker and Palumbi’s discoveries, and suggest ways this research is important or could be expanded upon.