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 A Map of the Cell’s Power Station
18.08.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau

nachricht On the way to developing a new active ingredient against chronic infections
18.08.2017 | Deutsches Zentrum für Infektionsforschung

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

A Map of the Cell’s Power Station

18.08.2017 | Life Sciences

Engineering team images tiny quasicrystals as they form

18.08.2017 | Physics and Astronomy

Researchers printed graphene-like materials with inkjet

18.08.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>