How Coral Reefs Work

2/9/2012, 1:52:57 PM , duration(0:0:2)
Society & Culture
Coral reefs are the largest organic structures on Earth, yet they're created through a symbiotic relationship between creatures about 3 millimeters long. Learn more about the the world's coral reefs (and how to protect them) in this episode.<br><br>Learn more about advertising on the HowStuffWorks podcasts at <a href='http://www.howstuffworks.com/advertisers.htm'>www.howstuffworks.com/advertisers.htm</a><br><br>And to learn about your ad choices when listening to podcasts, visit <a href='https://www.howstuffworks.com/privacy.htm#ad-choices'>https://www.howstuffworks.com/privacy.htm#ad-choices</a>