Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Drilled shells show extinction’s lasting effects

27.12.2004


Give a marine snail an easy life, and it will take its time drilling into a clam. Put it under competitive stress, and it will look for a faster route. Those changes, scarred into fossils, show that an unknown catastrophe nearly two million years ago changed the competitive balance in the Western Atlantic and the ecosystem has yet to fully recover, according to research published this week in the journal Science.



In the seagrass meadows of the Gulf of Mexico, Chicoreus and Phyllonotus marine snails feed on Chione clams by slowly drilling a hole through the shell wall. That process can take a week, while the snails risk losing their prey to another snail or being attacked themselves by fish, crabs or other predators.

High levels of competition should favor faster feeding, said Geerat Vermeij, professor of geology at UC Davis and an author on the paper. The snails can get a quicker meal by drilling through the thinnest part at the shell’s edge -- but risk getting their feeding proboscis nipped off by the closing shell.


The pattern of drill holes in fossil shells can give insight into what life in the ocean was like millions of years ago and how it compares to today.

In the laboratory, Gregory Dietl, a postdoctoral researcher at the University of North Carolina who is now at Yale University, UC Davis graduate student Gregory Herbert (now at the University of South Florida) and Vermeij found that when modern-day snails had to compete for food with other snails, they began edge-drilling their prey. When they were separated, they went back to slow wall drilling.

"They have the same gene pool, but you can elicit different behaviors depending on the competitive environment," Vermeij said.

A severe but regional extinction event at the end of the Pliocene Epoch 1.7 million years ago seems to have tilted the balance from high competition to low competition, according to the researchers. At that time, up to 70 percent of marine species in the Western Atlantic Ocean disappeared, with some parts of the world affected to a lesser extent and others unscathed.

The researchers looked at thousands of fossil clam shells from before and after the extinction and compared them with modern shells. Edge-drilled shells are abundant up to 1.7 million years ago, and then disappear entirely. None of the modern shells they looked at show edge-drilled holes.

The results show that competition intensity has not returned to pre-extinction levels even though a long time has passed since the event, Vermeij said.

The cause of the Pliocene extinction remains unknown. The work is published in the Dec. 24 issue of Science.

Andy Fell | EurekAlert!
Further information:
http://www.ucdavis.edu

More articles from Ecology, The Environment and Conservation:

nachricht Upcycling 'fast fashion' to reduce waste and pollution
03.04.2017 | American Chemical Society

nachricht Litter is present throughout the world’s oceans: 1,220 species affected
27.03.2017 | Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

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

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Fighting drug resistant tuberculosis – InfectoGnostics meets MYCO-NET² partners in Peru

28.04.2017 | Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

 
Latest News

Wireless power can drive tiny electronic devices in the GI tract

28.04.2017 | Medical Engineering

Ice cave in Transylvania yields window into region's past

28.04.2017 | Earth Sciences

Nose2Brain – Better Therapy for Multiple Sclerosis

28.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>