Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Extreme climate change linked to early animal evolution

27.09.2012
UC Riverside geoscientists help tie spike in ancient oceanic oxygen levels to 'Snowball Earth' event

An international team of scientists, including geochemists from the University of California, Riverside, has uncovered new evidence linking extreme climate change, oxygen rise, and early animal evolution.


This photo shows researchers studying exposures of the Doushanto Formation. Located in China, the formation is most notable for its scientific contributions in the hunt for Precambrian life.

Credit: M. Kennedy

A dramatic rise in atmospheric oxygen levels has long been speculated as the trigger for early animal evolution. While the direct cause-and-effect relationships between animal and environmental evolution remain topics of intense debate, all this research has been hampered by the lack of direct evidence for an oxygen increase coincident with the appearance of the earliest animals — until now.

In the Sept. 27 issue of the journal Nature, the research team, led by scientists at the University of Nevada, Las Vegas, offers the first evidence of a direct link between trends in early animal diversity and shifts in Earth system processes.

The fossil record shows a marked increase in animal and algae fossils roughly 635 million years ago. An analysis of organic-rich rocks from South China points to a sudden spike in oceanic oxygen levels at this time — in the wake of severe glaciation. The new evidence pre-dates previous estimates of a life-sustaining oxygenation event by more than 50 million years.

"This work provides the first real evidence for a long speculated change in oxygen levels in the aftermath of the most severe climatic event in Earth's history — one of the so-called 'Snowball Earth' glaciations," said Timothy Lyons, a professor of biogeochemistry at UC Riverside.

The research team analyzed concentrations of trace metals and sulfur isotopes, which are tracers of early oxygen levels, in mudstone collected from the Doushantuo Formation in South China. The team found spikes in concentrations of the trace metals, denoting higher oxygen levels in seawater on a global scale.

"We found levels of molybdenum and vanadium in the Doushantuo Formation mudstones that necessitate that the global ocean was well ventilated. This well-oxygenated ocean was the environmental backdrop for early animal diversification," said Noah Planavsky, a former UCR graduate student in Lyons's lab now at CalTech.

The high element concentrations found in the South China rocks are comparable to modern ocean sediments and point to a substantial oxygen increase in the ocean-atmosphere system around 635 million years ago. According to the researchers, the oxygen rise is likely due to increased organic carbon burial, a result of more nutrient availability following the extreme cold climate of the 'Snowball Earth' glaciation when ice shrouded much of Earth's surface.

Lyons and Planavsky argued in research published earlier in the journal Nature that a nutrient surplus associated with the extensive glaciations may have initiated intense carbon burial and oxygenation. Burial of organic carbon — from photosynthetic organisms — in ocean sediments would result in the release of vast amounts of oxygen into the ocean-atmosphere system.

"We are delighted that the new metal data from the South China shale seem to be confirming these hypothesized events," Lyons said.

The joint research was supported by grants from the National Science Foundation, the NASA Exobiology Program, and the National Natural Science Foundation of China. Besides Lyons and Planavsky, the research team includes Swapan K. Sahoo (first author of the research paper) and Ganqing Jiang (principal investigator of the study) of the University of Nevada, Las Vegas; Brian Kendall and Ariel D. Anbar of Arizona State University; Xinqiang Wang and Xiaoying Shi of the China University of Geosciences (Beijing); and UCR alumnus Clint Scott of United States Geological Survey.

The University of California, Riverside is a doctoral research university, a living laboratory for groundbreaking exploration of issues critical to Inland Southern California, the state and communities around the world. Reflecting California's diverse culture, UCR's enrollment has exceeded 20,500 students. The campus will open a medical school in 2013 and has reached the heart of the Coachella Valley by way of the UCR Palm Desert Center. The campus has an annual statewide economic impact of more than $1 billion. A broadcast studio with fiber cable to the AT&T Hollywood hub is available for live or taped interviews. UCR also has ISDN for radio interviews. To learn more, call (951) UCR-NEWS.

Iqbal Pittalwala | EurekAlert!
Further information:
http://www.ucr.edu

More articles from Earth Sciences:

nachricht Climate satellite: Tracking methane with robust laser technology
22.06.2017 | Fraunhofer-Gesellschaft

nachricht How reliable are shells as climate archives?
21.06.2017 | Leibniz-Zentrum für Marine Tropenforschung (ZMT)

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

Im Focus: Optoelectronic Inline Measurement – Accurate to the Nanometer

Germany counts high-precision manufacturing processes among its advantages as a location. It’s not just the aerospace and automotive industries that require almost waste-free, high-precision manufacturing to provide an efficient way of testing the shape and orientation tolerances of products. Since current inline measurement technology not yet provides the required accuracy, the Fraunhofer Institute for Laser Technology ILT is collaborating with four renowned industry partners in the INSPIRE project to develop inline sensors with a new accuracy class. Funded by the German Federal Ministry of Education and Research (BMBF), the project is scheduled to run until the end of 2019.

New Manufacturing Technologies for New Products

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

A new technique isolates neuronal activity during memory consolidation

22.06.2017 | Life Sciences

Plant inspiration could lead to flexible electronics

22.06.2017 | Materials Sciences

A rhodium-based catalyst for making organosilicon using less precious metal

22.06.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>