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  **footnote: Click on the video to watch. Need to know what a coral is? Read our handy guide below:

A coral is an animal. It is the thin layer of living tissue that covers a hard structure called the coral skeleton.

The coral builds this structure layer by layer by causing calcium carbonate (a.k.a. limestone) to be deposited on the existing skeleton. Coral structures can grow to different shapes, depending on the species. Some look like boulders, others like tree branches or even heads of lettuce.

Most corals get their color from algae that live inside the coral tissue. The algae have a symbiotic relationship with the coral: the coral hosts the algae and, in exchange, the algae take energy from the sun (through photosynthesis) and share it with the coral.

Coral bleaching occurs when this symbiotic relationship breaks down and the algae is ejected from the coral.

Kate Furby is a Marine Biology grad student at the Scripps Institution of Oceanography, U. California San Diego. In the video above, she explains her research of looking at how coral reefs recover from these catastrophic events.

Using a rig she calls the 'Photomegatron', Kate surveys coral reefs in different parts of the world, looking at how some species of coral are seemingly wiped out by a bleaching event, and then slowly come back from the dead.

Click Here to see the video.

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A Message from Jorge -

You may have noticed the huge banner below each comic. I apologize if it's too big, but I'm very excited to announce that my new book is on sale! We Have No Idea is a fun and accessible book about the Universe and how little we know of it. It's full of clear and fun explanations and cartoons. I spent a whole year working with physicist Daniel Whiteson to create the book, so it would be awesome if you took a moment to check it out and consider buying it!

When we wrote it, we were inspired to make a book that doesn't just talk about what we know, but also what we don't know about the Universe. How else will the next generation of scientists and explorers be inspired to go out there and expand our horizons?

So take a look, and consider buying it for yourself or gifting it to a friend or family member who is graduating! What better present than a book about everything we don't know?

Thank you all for supporting all my crazy efforts (movies, videos, books) over the years! I hope you enjoy the book!


WE HAVE NO IDEA Release! - My new book is now on sale! Order it now!

And check out the book tour map and come see us at one of many fun events!

PHD Store - Our store was down for a while, but now it is back!

Free excerpt from The PHD Movie 2! - Watch this free clip from the movie that Nature called "Astute, funny"!

Watch the new movie! - The PHD Movie 2 screenings are in full swing! Check out the schedule to catch the screening nearest you.

Filming is done! - Take a sneak peek behind the scenes of the new PHD Movie 2:

Coming to Campuses this Fall!
Stay tuned for updates on how to organize a screening at your University.

The Science Gap - Watch Jorge's TEDx Talk:

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