To celebrate the arrival of our new Geology Curator, Neil Owen, Natural Science Curator Clare Brown created the Lemon Drizzle Crinoid Cake – celebrating a mysterious creature from the oceans.
Looks can be deceiving as crinoids are animals not plants. They are members of the phylum Echinodermata. This group of animals is made up of starfish, sea urchins, sand dollars, sea cucumbers and sea lilies. First appearing in the fossil record during the Early Ordovician, 480 million years ago and survived to present day. They were prolific from the Carboniferous to the Cretaceous with over 6000 species discovered.
The seas at this time would have been teeming with crinoids gracefully swaying in the currents, almost resembling plants in the breeze.
Unlike their relations, they developed a unique body structure with a body (calyx) was covered in a flexible membrane and was made up of interlocking plates, held aloft by a long stem made of individually stacked plates (ossicles)to form a column. At the base of this column they attached themselves to the sea floor with a root like structure (holdfast). On the upper surface of the body they developed arms (brachials) with tiny filaments (pinnules) to filter the passing water currents.
Unfortunately this body plan has been lost in time as modern crinoids have evolved to resemble sea urchins and are entirely mobile.
You can learn more about our Geology Collections over on the #GeoBlitz blog.
By Lucy Moore, First World War Projects Curator