Cryogenic tissue preservation using liquid nitrogen was used to gather cell cultures of tooth forming cells that will be examined in the laboratory. Using a combination of established protocols (Whitehead Institute, MIT), tests conducted in the laboratory (Enders Research Facility, Children's Hospital/Harvard Medical School) and field experience on expedition in 2003, an expedition protocol for 2004 has been established. Samples placed in a liquid nitrogen dry-shipper will be transported to laboratories at The Forsyth Institute and the Department of Orthopaedic Surgery, Children's Hospital, Boston. The Principal Investigator is certified in the handling and shipping of hazardous materials. Tissue collection in this study involves one of the most extensive applications of knowledge for an investigator to both collect, handle and ship tissue preserved specimens during field research. As IATA regulations for shipping and transport of hazardous materials are exacting and rigorous, such training was imperative and proved successful in the transport of tissue samples in 2003. The tusk will be examined as a sensory probe. Although there have been isolated accounts of the narwhal tusk considered as a sensory organ (Best, 1972), no one, to our knowledge, has conducted conclusive tests to support such a theory. Because of the unusual tusk helix, dentinal crystal patterns formed during development may contribute to a Piezo effect (Bassett and Becker, 1962; Kay et al., 1964; Freeman, 1966; Shamos and Levine 1967) defined as an electrical potential created from the distortion or stress of atoms within a crystal. There exists precedence in other aquatic fauna such as the paddle fish (Wojtenek et al., 2001) and platypus (Fjallbrant et al., 1988) for electric and electromagnetic fields to influence the feeding habits of these species.  The possibility of the tusk as a transmitter or receiver of sound will also be explored (Harding and Harker, 1998). Field observations of captive narwhal support the possibility of tusk sound transmission from accounts of vibrations felt along the tusk during vocalizations (Best, 1972). Aerial photographs and field observations reveal a tusk emergence angle diverging from the midline of the body axis in both a horizontal and vertical plane. The male tusk position places a drag on the whale during movement but may be suited for sensory function.