ABSTRACT
All organisms face demands imposed by the physical world and exhibit movements that are dependent on the material properties of the media in which they live. Aquatic life, for example, faces a very different set of physical challenges than organisms on land (Denny, 1993), and such physical constraints may set boundary conditions for the design of organisms in media such as air and water. Furthermore, virtually every aspect of organismal design, including patterns of skeletal organization, movement, sensory biology, prey capture, osmoregulation, and circulatory function, is significantly affected by the environment inhabited by organisms. As movement is the major feature of many behaviours, the behaviour of organisms must also be subject to physical constraints imposed by the environment (see also Chapter 1).
