Felix G. Marx is Curator Vertebrates at the Museum of New Zealand Te Papa Tongarewa, where he primarily looks after the marine mammal collection. Prior to becoming a curator, he spent several years as a postdoctoral fellow in Australia, Belgium and Japan. He specialises in the evolution of baleen whales, but has worked on a broad variety of topics, from macroevolution to feeding ecology, biogeography, and behaviour. Dr Olivier Lambert is a vertebrate palaeontologist at the Institut royal des Sciences naturelles de Belgique, Brussels. Interested in the secondary adaptations of mammals to the marine environment, Dr Lambert studies fossil cetaceans from many geological ages and localities in the world. Most of his publications focus on extinct echolocating toothed whales, especially from the North Atlantic and South-East Pacific realms. Dr Mark D. Uhen is an Assistant Professor of Geology at George Mason University. Dr Uhen�s research focuses on the origin and evolution of cetaceans (whales and dolphins), and other marine mammals. He has conducted field work around the world, developed exhibits and lessons on cetacean evolution for museums, and published on his work in journals, and books. Dr Uhen is also a leader of the Paleobiology Database, an on-line open resource that documents every fossil occurrence on the planet.