Prelude to the anthology in memory of Donald Richard Nelson

Abstract

There are few people on this planet who could not tell you something about the behavior of the sea creature known as the shark. Ask most people and they will likely cite voracious feeding and aggressive behaviors, but ask a shark scientist and you will get a very different answer. In truth, information on the natural behavior of sharks is known for only a few of the more than 350 species. Even less is known about their cousins, the more than 450 species of derived rays and skates. The main reason for this great void is that elasmobranch fishes are relatively large, wide-ranging, and live in an inhospitable and secretive environment. Thus they are relatively difficult to observe in the field or study under laboratory conditions. The same reasons explain why so little is known of how the sensory systems of these animals function in natural settings. As a result, much of what we know about the natural behavior of sharks and rays comes from brief field studies conducted without a premeditated paradigm or experimental design.