Final answer:
The characteristic of having large molar teeth relative to body size in primates is associated with efficient processing of tough plant materials.
Step-by-step explanation:
In the context of dental anatomy and primatology, the characteristic of having large molar teeth relative to body size is described as a trait seen in many primate species, including humans. This characteristic is associated with the ability to efficiently process and grind tough plant materials. For example, the robust australopithecines had large molars and strong jaw muscles to chew tough vegetation. In modern humans, our relatively large molars are thought to be remnants from our evolutionary ancestors who relied heavily on plant-based diets.