Published: November 2007
Learn More
In Learn More the National Geographic magazine team shares some of its best sources and other information to expand your knowledge of our featured subjects. Special thanks to the Research Division.
Related Links

Census of Marine Life
See some of the images of marine microfauna taken by biological oceanographer Russ Hopcroft during his expedition off Australian waters.

Glaucus atlanticus
Learn about this flamboyant creature through the sea slug forum, and navigate the site to discover other nudibranchs that inhabit the sea.

Ocean Acidification Network
This site is chock-full of information on ocean acidification. You can find publications, an events calendar, video clips, and radio downloads that discuss the latest on this alarming trend.


Hanlon, Roger T., and John B. Messenger. Cephalopod Behaviour. Cambridge University Press, 1996.

Hoover, John P. Hawai'i's Sea Creatures: A Guide to Hawai'i's Marine Invertebrates. Mutual Publishing, 1999.

Kleypass, Joan A., and others. Impacts of Ocean Acidification on Coral Reefs and other Marine Calcifiers: A Guide for Future Research. National Science Foundation, U.S. Geological Survey, and National Oceanic and Atmospheric Administration. June 2006. Available online at

Orr, James C., and others. "Anthropogenic Ocean Acidification Over the Twenty-First Century and Its Impact on Calcifying Organisms." Nature (September 29, 2005), 681-86.

Pagani, Mark, and others. "An Ancient Carbon Mystery." Science (December 8, 2006), 1556-57.

Royal Society. Ocean Acidification Due to Increasing Atmospheric Carbon Dioxide. June 2005.

Valdés, Angel, and Orso Angulo Campillo. "Systematics of Pelagic Aeolid Nudibranchs of the Family Glaucidae (Mollusca, Gastropoda)." Bulletin of Marine Science (November 2004), 381-89.

Zachos, James C., and others. "Rapid Acidification of the Ocean During the Paleocene-Eocene Thermal Maximum." Science (June 10, 2005), 1611-15.

NGS Resources

Krajick, Kevin. "Discoveries In the Dark: Troglobites." National Geographic (September 2007), 134-47.

Liittschwager, David and Susan Middleton. "Hawaii's Outer Kingdom." National Geographic (October 2005), 70-91.