Investigating the question: Does size of an organism change based on oxygen levels available in the environment?

Students will analyze modern fossil records of four different species of a group of organisms called foraminifera, which are single celled protists with shells (tests). All of the specimens were collected from the Santa Monica Basin in the Pacific Ocean just off of Santa Monica, California. There are numerous sample sites in the basin and the sites differ by the amount of available dissolved oxygen (categorized by low oxygen, suboxic, dysoxic, and anoxic amounts). Current evidence indicates that greater oxygen availability leads to larger organisms. In recording foram measurements and counting shell chamber divisions, students will generate enough data to determine if there is a noticeable trend that relates specimen size to oxygen availability.