This is video two in a three video series. This video continues from the introduction to describe how plants have their leaves in certain arrangements, and how this relates to the Fibonacci series. It is a good video to illustrate the unity of knowledge in math and science, as well as exhibiting the unity and diversity of life (both of these are related to course learning objectives in all CLSE courses). The comments and questions below the video on the site are useful for follow up and to generate class discussion (or quiz questions!). Note: The narrator speaks fast, and does not pause. Repeating and/or discussing the video between this and the next part may be necessary for some students. www.khanacademy.org. NOTE: All Khan Academy content is available for free at www.khanacademy.org