Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Is being big clam on the block a factor in species success?

25.10.2002


Body size is one of the most important biological characteristics in the study of organisms, telling a researcher a lot about how a particular animal lives and interacts with it’s environment and with other species. Despite this importance, there has been little study of body size trends of ancient life.



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 unchanged. The extinction itself wasn’t size selective," says Krause.

Another interesting point that Krause will focus on at the GSA meeting is the changing places of bivalves and brachiopods. "What we are finding is that from the early Ordovician to the Silurian, or between 500 million and 400 million years ago, bivalves were considerably bigger than brachiopods," says Krause. This is very similar to the present-day situation for these groups. Bivalves living in the oceans today are, on average, significantly larger than modern brachiopods.

But, while their size differences haven’t changed much, these groups have done a major switch ecologically over the last 400 million years. Brachiopods were very diverse and successful in the Ordovician and Silurian, while bivalves were somewhat rare in many environments. The situation is exactly reversed in modern oceans, says Krause.

"This seems to say that diversity and evolutionary success may not have anything to do with how big an organism is. In this case, the culprit is likely the fact that bivalves’ metabolism is higher. They are more active. That may be what is controlling size, rather than environment," says Krause. "The fact that this size difference seems to have not changed in the last 400 million years despite major ecological changes is really interesting, and a bit unexpected."

Krause will present the paper, "Differences in size of early Paleozoic bivalves and brachiopods: The influence of intrinsic and extrinsic factors on body size evolution," at 9:15 a.m. on Sunday, Oct. 27 in Room A108/110 at the Colorado Convention Center. Co-authors are Stempien, Virginia Tech geological sciences professor Michal Kowalewski, and Arnold I. Miller at the University of Cincinnati.


Contact information: Richard Krause. rkrause@vt.edu. 540-231-1840

Richard Krause’s major professor is Michal Kowalewski.

PR Contact: Susan Trulove, strulove@vt.edu, 540-231-5646.

Richard Krause | EurekAlert!
Further information:
http://www.technews.vt.edu/

More articles from Life Sciences:

nachricht Navigational view of the brain thanks to powerful X-rays
18.10.2017 | Georgia Institute of Technology

nachricht Separating methane and CO2 will become more efficient
18.10.2017 | KU Leuven

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Osaka university researchers make the slipperiest surfaces adhesive

18.10.2017 | Materials Sciences

Space radiation won't stop NASA's human exploration

18.10.2017 | Physics and Astronomy

Los Alamos researchers and supercomputers help interpret the latest LIGO findings

18.10.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>