Compensatory Scope and Resource Allocation in Two Species of Aquatic Snails

The resource allocation strategies of the freshwater snails Stagnicola elodes and Physella gyrina were examined using artificial diets diluted to various degrees with cellulose. Even when nutrients were diluted by 50 or 75%, both species showed remarkable maintenance of their rates of assimilation (94 to 294% of controls) and production (82 to 140% of controls). This was mainly achieved by varying rates of feeding (148 to 397% of controls) and …