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Bivalve of the Day |
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Adams’ Miniature Ark
Arcopsis adamsi (Dall, 1886)
Family Noetiidae (False Ark Clams)
A group of Arcopsis crowd closely together on the undersurface of a rock from the bayside of Spanish Harbor Key in the Florida Keys. When the rock is turned over, the disturbed individuals voluntarily release their strong byssus threads and crawl away from the light. The blood of Arcopsis adamsi is known to contain hemoglobin. Members of the family Noetiidae are closely related to the true arks (Arcidae), but differ in the structure of the ligament joining their shells. The family is known since the Cretaceous Period, is represented by 13 living genera and ca. 40 species, and is widely distributed in shallow waters.
Evolution on the Half Shell...
The Assembling the Tree of Life: Bivalvia project (BivAToL) is a part of the Assembling the Tree of Life initiative, a large research effort sponsored by the National Science Foundation. Its goal is to reconstruct the evolutionary origins of all living things.
Jetsam & Flotsam
Some of the BivATOL team met in early May at the Mote Marine Laboratory’s Tropical Research Station at Summerland Key, FL for a combined collecting trip and coding workshop. Both activities are essential to our project’s goal of determining the phylogenetic relationships among the bivalve families.
After collection, many of the species’ visible and molecular characteristics must be compared and “coded,” after which the phylogenetic computer analyses will be run to produce the final “tree” from which a hypothesis of relationships can be made. Below is an example of a portion of such a phylogenetic tree. Families that are on nearby branches are more closely related to each other than those further away.
Here, Mya is more closely related to Dreissena (zebra mussels) than to Teredo (shipworm clams).
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