This lesson is designed to accompany a short film by HHMI BioInteractive. In the film, Penn State University anthropologist Dr. Nina Jablonski discusses the evidence for the natural selection of human skin color. She describes how the phenomenon of skin color variation is related to both global distribution of UV intensity and the need for the skin to absorb some UV to produce vitamin D. The video briefly covers related topics in physiology, UV light absorption, genetics, and gene regulation. A student worksheet is designed to accompany the video, but partitions the information into shorter sections with additional data. Students use this data to make predictions about how skin color has evolved over time to include the variety of pigments we see around the world today. Besides the video and student worksheet, this resource includes educator materials, a film guide, and a video about additional educator tips. A Spanish version of all materials is also available.