Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Plant Evolution Led to Permanent Changes to the Way Rivers Looked and Behaved

27.01.2010
Cast your mind back, oh, about 420 million years ago. There are giant fish swimming in the oceans, but it’ll be nearly another 200 million before dinosaurs and the first mammals arrive on the scene.

This is a time of continents colliding, North America and Greenland hitting Europe, smashing together and making mountains. The planet’s land mass is mostly dusty and barren. Rivers were more like great expanses of water sliding into the ocean.

“You’d hardly know the place,” says Martin Gibling, professor with Dalhousie’s Department of Earth Sciences. “There was bare rock and sand, with crusts of bacteria and algae over the rock surfaces. And ancient rivers were very different, like big sheets of water carrying sand and gravel. They weren’t like channels whatsoever.”

Dr. Gibling and postdoctoral researcher Neil S. Davies wanted to find out more about those big rivers. What happened during the evolution of the Earth to throw them for a loop?

“If you think of a river, it’s wavy, it’s meandering,” explains Dr. Gibling. “A river has curves, eroding into its bank on one side, and depositing sediments on the other.”

For the answers to one of the most significant environmental changes in the Earth’s history, they turned to the fossil record using a literature compilation and fieldwork. Their research took them to 35 sites around the globe, including Port-au-port, Newfoundland, the Gaspé Peninsula of Quebec, the Channel Islands off the coast of France and Death Valley in California.

The difference, they discovered, was the earliest plants, stretching their roots down and stabilizing river banks. Instead of wide and sheet-like, rivers evolved to become more confined and narrower. Their research, highlighting the co-evolution of land plants and river landscapes, has just been published in the journals Geology and Earth-Science Reviews.

“Once the plants started to get a toehold, they sent spores into more inland areas,” says Dr. Davies, who hails from Birmingham, England. “The entire process took about 50 million years, with vegetation spreading until it dominated every landscape except total desert. The Earth could never be the same again.”

SEE: “Cambrian to Devonian evolution of alluvial systems: The sedimentological impact of the earliest land plants” in Earth-Science Reviews, February 2010

“Paleozoic vegetation and the Siluro-Devonian rise of fluvial lateral accretion sets” in Geology, January 2010

Charles Crosby | Newswise Science News
Further information:
http://www.dal.ca

More articles from Earth Sciences:

nachricht NASA finds newly formed tropical storm lan over open waters
17.10.2017 | NASA/Goddard Space Flight Center

nachricht The melting ice makes the sea around Greenland less saline
16.10.2017 | Aarhus University

All articles from Earth 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 >>>