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FOSSIL BRACHIOPODS FOR SALE
What Are Brachiopods?
Brachiopods are members of the phylum Brachiopoda. They are clam-like creatures with wide shells composed of two halves called valves. They are filter feeders that live affixed to rocks or on the seafloor.
When Did Brachiopods First Appear In The Fossil Record?
Brachiopods first appeared in the early Cambrian in simple forms with non-articulating shells. Their diversity peaked during the Devonian. There are 12,000 described fossil species of Brachiopoda from 5,000 genera.
When Did Brachiopods Die Out?
Most species of brachiopod died out during the Permian-Triassic Extinction, but there are about 450 species living today. They live in cold marine environments like polar seas or continental shelves and slopes.
What Do Brachiopods Look Like?
At first glance, brachiopods look like clams or other bivalve molluscs. Their shells are composed of two halves (valves). Each half has symmetry across a midline. They have two different sized shells: the bottom is slightly larger than the top. In addition, brachiopods have holes in their bottom shells where their anchoring organ, called a pedicle, comes through. They are also known as lamp shells because they resemble ancient Greek oil lamps.
What Do Brachiopods Eat?
Brachiopods are filter feeders! They filter plankton and other nutrients from the water around them.
How Do Brachiopods Move?
Most Brachiopods do not move. They attach themselves to a rock or shell and remain in that location as long as they are able to attach to it. A few species move short distances by extending their pedicle (foot), attaching to an object and pulling themselves toward it. This is not an energy-efficient way to move, so brachiopods that employ this method never move more than a few inches or feet.
How Big Are Brachiopods?
The largest fossil brachiopod is 7.9 inches (200 mm) wide, but most are 2-4 inches (3-8 cm). Living brachiopods also fall into this range.
Where Do Brachiopods Live?
Today, brachiopods live in cold marine environments like polar seas and continental shelves and continental slopes. The diversity of fossil species suggests that Devonian brachiopods occupied most of the marine environments that existed at the time. It is likely that they lived in cold polar waters and warm seas, from the deep ocean to shallow bays. Some probably even lived in water with low salinity, like river mouths and estuaries.
What Are The Differences Between Brachiopods And Clams?
Both these animals look similar to each other, but brachiopods are more closely related to bryozoans than molluscs. The easiest differences to identify are in their shells. Mollusc shells, like clams, are divided between left and right, while Brachiopod shells are divided between top (dorsal) and bottom (ventral). Mollusk shells are about equal size, but in brachiopods, the bottom shell is larger than the top.
The other big difference is in how they feed. Both are filter feeders, but mollusks extend their filters into the water and pull food into their shells. Meanwhile, brachiopods have internal feeding structures. They draw into their shells where food is filtered before expelling it out.