Abstract:
General Information: With the digestive system, almost more than any other, it is clear that form is intimately determined by function. Of all systems, it is the gut that shows perhaps the least constancy of pattern within a group. While its distinct form may be in general the outcome of evolutionary affinity and descent, special adaptations will repeatedly present themselves to deal with particular types of food. In some groups adaptive diversity appears great; in others there appears to be an inherited stereotype with relatively little adaptive variation.