Family Pteriidae (Pearl Oysters)
This is a “shell midden.” That’s basically a garbage pile as a result of human harvesting — in other words, someone collected and ate these clams, then discarded the shells in one pile, called a shell midden, kitchen midden, or shell heap. Historically, middens have told scientists a lot about the collecting and food habits, and even the range of travel, of native peoples around the world. This one tells us that the native aboriginal inhabitants on North Stradbroke Island eat pearl oysters, which is relatively unusual in our Western experience (although pearl oysters are also commonly eaten in Japan and northern Australia). This midden includes several species of Pinctada, including P. imbricata (Roeding, 1798) and P. albina (Lamarck, 1819). The photo was taken in front of the marine station during BivAToL’s expedition to Moreton Bay in October 2008.
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.