Here's why:
* Diet: Their diet consists mainly of algae, seaweed, and other plant matter. They use their beak-like teeth to scrape algae off rocks and coral.
* Digestive System: Their digestive system is adapted to breaking down plant matter.
* Role in the Ecosystem: Parrotfish are crucial to maintaining coral reef health. They help control algae growth and prevent it from smothering coral.
While they are primarily herbivores, there's some evidence suggesting they may occasionally consume small invertebrates like plankton or worms. But this is not a significant part of their diet.