Now, using marine life forms as models, three Virginia Tech doctoral students in geological sciences have launched a long-term research project to see what can be learned about life across millions of years. At the Geological Society of America's 114th annual meeting in Denver, Oct. 27-30, Richard Krause Jr. will present early findings from his, Jennifer Stempien's, and Susan Barbour Wood's work.
So far, findings suggest that body size may not be directly related to evolutionary or ecological success.
The trio focused initially on bivalves and brachiopods. Bivalves, which include clams, mussels, and scallops, and brachiopods, which appear similar to clams but have a fundamentally different anatomy, are easily compared because "there is a really good fossil record for both groups," says Krause.
The scope of the project is huge. The researchers want to measure what has happened all over the world and over millions of years. "Obviously we can't go out and collect fossils from each age and area," says Krause. So they are using photographs that accompany published research. This way they can look at and measure shells from many different time periods all over the world.
The research is already yielding some promising results. The students report that early in the history of life, size of the organisms from these groups was increasing along with diversity, which has not been previously documented. "Most interesting, as diversity begins to drop at the end of the Ordovician period, during a major extinction interval (440 million years ago), the overall size of the organisms of both groups was unch
Contact: Richard Krause