Theodore H. Bullock
Cetaceans present unique opportunities for new insights into the mammalian brain--the highest achievement of evolution. Some species possess the greatest brains in nature, at least in respect to size. The brains are remarkably specialized in many ways, compared to those of other mammals. They have been evolving separately from other mammals for a long time. Their cognitive achievements, although not yet fully assessed, their special sensory capacities, acoustic signaling, songs, and other behavioral features add reasons that the correlates in brain anatomy, physiology, and chemistry should be studied for clues to understanding how brains mediate cognition and behavior.
In spite of these strong reasons and the great interest in dolphins and whales, their brains are relatively little studied and our knowledge lags well behind that for other orders of mammals. Extraordinary difficulties lie in the path of investigation of cetaceans, even of anatomy. The overriding difficulty is scarcity of material and access permitting the use of modern methods. A quite proper reluctance to sacrifice specimens of these magnificent species has almost completely prevented the use of the most revealing modern techniques of experimental anatomy for tracing connections by allowing the living nerve cell to distribute substances it takes up into all it axonal and dendritic processes--methods