Final answer:
The oldest fossil evidence for Paranthropus indicates they had large teeth and strong chewing muscles suited for a tough vegetarian diet 2.5 million years ago.
Step-by-step explanation:
Paranthropus Fossils and Dental Morphology:
The oldest fossil evidence for Paranthropus dates back to approximately 2.5 million years ago. These hominids stood out particularly for their powerful muscles and significantly large teeth, adapted for consuming a coarse, fibrous vegetarian diet. Notably, Paranthropus had large grinding teeth and a facial structure that could accommodate strong chewing muscles, such as a sagittal crest for the attachment of large temporalis muscles, indicating an adaptation for a diet composed mainly of hard nuts and seeds. The robust characteristics of Paranthropus robustus further support this, with heavy wear on molars showing a relationship to their diet. Unlike the austral piths that had teeth suited for soft food, Paranthropus species developed dental and skull features conducive to processing tougher plant material.