Brachiopods are marine animals belonging to their own phylum, Brachiopoda, of the animal kingdom, that have hard "valves" on the upper and lower surfaces, unlike the left and right arrangement in bivalve molluscs. Brachiopod valves are hinged at the rear end, while the front can be opened for feeding or closed for protection.

Brachiopods have a very long history of life on Earth (at least 550 million years). They first appear as fossils in rocks of earliest Cambrian age, and their descendants survive, albeit relatively rarely, in today's oceans and seas.
 
Brachiopod die-off signaled mid-Permian mass extinction. The biggest of these happened toward the end of the Permian Period about 252 million years ago, when 95 percent of all species went extinct. [read more at www.bgs.ac.uk]
 
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