This activity supports concepts covered in the short film The Day the Mesozoic Died by replicating observations and measurements made by researchers of fossilized protists, called foraminifera (or forams), below and above the K-T boundary.

Students will use photomicrographs of foram research samples to note the differences in the fossils, mirroring those made by researchers documenting a mass extinction event at the end of the Cretaceous period about 66 million years ago.

This activity has three parts which complement Act 1 of the short film The Day the Mesozoic Died. Part 1 is a foram-sorting activity using the Foraminifera cards that students complete before watching the film. In Part 2, students analyze the data on forams found near the K-T boundary, and in Part 3, students compare data related to the size of the forams.