A Silurian mystery - Did the animals live in the positions that we find them in now as fossils?

Wenlock slab with close-up area highlighted for orientation purposes

soliatry coral lying on its back

This coral should be standing up with its wide feeding end well above the muddy sea floor. For some reason it has fallen over.



a brachipod and net-like bryozoans

Brachiopods have a pair of shells, and live with one shell on top of the other. The shells have slightly different shapes so it is possible to work out which is the top shell and which is the bottom one. Brachiopods which lived on a muddy seafloor often have curved edges to their shells to help keep the mud out of their bodies when their shells open up to feed.

Net-like bryozoans would have stood upright so that each tiny animal living in the holes could feed on the tiny plankton and other food particles carried in the sea water. They would not have been happy lying stacked up and overlapping as these bryozoans are.



colonial coral

Coral colonies like to live well above the sea floor where there is plenty of food in the water to support the coral animals (polyps), and the water is clean and sunlit. This colonial coral could not have lived on the sea-floor as the muddy sediment would have clogged its delicate feeding structures.



Are all of the fossils broken?

Why are some of the fossils broken?

Continue the investigation ...

Wenlock Creatures

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