In this video segment adapted from NOVA, evolutionary scientist Sean Carroll investigates why one species of fruit fly has wing spots while another genetically similar one does not. As the video explains, although two organisms may both possess the same gene linked to a particular trait, this trait may not be expressed unless the gene is turned on. This is done by an enhancer, a piece of noncoding DNA—previously thought of as "junk" DNA—that acts as a "switch." This video is available in both English and Spanish audio, along with corresponding closed captions. CREDITS: https://www.pbslearningmedia.org/credits/novat10.sci.life.evo.fruitfly/ LICENSE: https://www.pbslearningmedia.org/help/full-license-for-section-3c-of-terms-of-use-download-and-share/
LicenseCustom License
The theory of how the Grand Canyon was formed is shown in this animation from NOVA, and features rare footage of a phenomenon known as debris flow. CREDITS: https://www.pbslearningmedia.org/credits/ess05.sci.ess.earthsys.canyon/ LICENSE: https://www.pbslearningmedia.org/help/full-license-for-secti
In this video from NOVA’s Sun Lab, learn about the Sun’s ever-changing surface and magnetic field. Images and animations illustrate how the Sun’s magnetic field lines are affected by the motion of the Sun’s plasma. Over time, the magnetic field becomes twisted and more complex, which increases solar
In this video from NOVA’s Sun Lab, learn about the Sun’s composition and structure. The Sun is a plasma, primarily made of hydrogen with smaller amounts of other elements. Animations and images illustrate the physical and behavioral properties of the Sun’s six regions: the core, radiative zone, conv
