John E. McCosker is a Senior Scientist and the Chair of Aquatic Biology at the California Academy of Sciences. Prior to that, he was Director of the Steinhart Aquarium, a division of the Academy, for 22 years. Born in Los Angeles in 1945, he received his PhD at the Scripps Institution of Oceanography in 1973 based on the evolution of tropical eels. His research activities have included such diverse topics as the fishes of the Galapagos Islands, the classification and relationships of the eel families Ophichthidae and Muraenidae, the symbiotic behavior of bioluminescent fishes, the behavior of sea snakes, the biology of the coelacanth, the behavior of white sharks, and the conservation of salmonid fishes. He is the author of more than 200 popular and scientific articles and books, and has made scuba and submersible dives throughout most of the tropics