First appeared in the fossil record roughly 550 million years ago, early in the Cambrian period.
Do you need to focus on a (e.g., Paleozoic vs. Mesozoic)? brachiopoda
Are you focusing more on their or their use as fossils ? I can expand any of these sections with more specific data. Brachiopods: They're Not Clams First appeared in the fossil record roughly 550
A stalk extending from the ventral valve used for attaching to substrate. held together by muscles.
Lack complex hinges, held together by muscles.