In this video Paul Andersen explains in more detail the history of the Earth. He shows how the history of the Earth is written in the rocks that are built up over time. Fossils allow us to compare different rock layers relative to one another and the absolute radiometric dating allows scientists to identify the specific age of individual rocks.
CCC7: Stability and Change
Paul Andersen explains how stability and change are regulated in systems through controls and feedback. Controls are used to regulate matter and energy flowing into a system. Feedback mechanisms within the system are used to regulate stability. Negative feedback loops keep the values around a set point and positive feedback loops move them away. Disequilibrium can result in death of living systems and destruction of physical systems. A progression of instruction for K-12 students is also included.
SEP6: Constructing Explanations and Designing Solutions
Paul Andersen explains how scientists modify theories by constructing explanations. He also discusses the cycle of design used by engineers to solve problems. He starts by defining a theory as a well-established explanation of a phenomenon that is refined over time. Examples discussed in the video include the big bang theory, the germ theory and the theory of natural selection. He also lays out a progression for building this skill in students.
